Updated kotlin gradle plugin

This reverts commit feebbd8ec7.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,8 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Auxilor Community Discord
+    url: https://discord.gg/ZcwpSsE/
+    about: Join the Auxilor discord to get help from support staff and the general community!
+  - name: The most common issues people have
+    url: https://github.com/Auxilor/eco/issues/78
+    about: Check the list of known common issues to see if your issue has already been solved

.github/ISSUE_TEMPLATE/report-a-bug.md

@@ -0,0 +1,31 @@
+---
+name: Report a Bug
+about: Report an issue with the plugin
+title: ''
+labels: bug
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior: 
+1. Go to '...'
+2. Click on '....'
+3. Scroll down to '....'
+4. See error
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Screenshots**
+If applicable, add screenshots to help explain your problem.
+
+**Server Information (please complete the following information):**
+- Version: (output of `/ver` command)
+- Version of plugin and eco (`/ver eco`, `/ver <plugin>`)
+
+**Additional context**
+Add any other context about the problem here.

.github/ISSUE_TEMPLATE/request-a-feature.md

@@ -0,0 +1,20 @@
+---
+name: Request a Feature
+about: Suggest an idea for this plugin
+title: ''
+labels: enhancement
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+**Additional context**
+Add any other context or screenshots about the feature request here.

.github/dependabot.yml

@@ -0,0 +1,11 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  - package-ecosystem: "gradle" # See documentation for possible values
+    directory: "/" # Location of package manifests
+    schedule:
+      interval: "daily"

.github/workflows/checkstyle.yml

@@ -0,0 +1,15 @@
+name: Check PR Codestyle
+on: [ pull_request ]
+
+jobs:
+  checkstyle:
+    name: Checkstyle
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dbelyaev/action-checkstyle@v0.5.1
+        with:
+          github_token: ${{ secrets.github_token }}
+          reporter: github-pr-review
+          level: warning
+          checkstyle_config: ../../config/checkstyle/checkstyle.xml

.github/workflows/java-ci.yml

@@ -0,0 +1,36 @@
+name: Java CI
+
+on: [ push, pull_request ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout latest code
+        uses: actions/checkout@v2
+
+      - name: Set outputs
+        id: vars
+        run: echo "::set-output name=sha_short::$(git rev-parse --short HEAD)"
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v2
+        with:
+          distribution: 'temurin'
+          java-version: 17
+
+      - name: Setup build cache
+        uses: actions/cache@v2.1.6
+        with:
+          path: ~/.gradle/caches
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle.kts') }}
+          restore-keys: |
+            ${{ runner.os }}-gradle-
+
+      - run: ./gradlew build --full-stacktrace
+
+      - uses: actions/upload-artifact@v2
+        with:
+          name: eco-dev-${{ steps.vars.outputs.sha_short }}
+          path: build/libs

.github/workflows/publish-release.yml

@@ -12,11 +12,11 @@ jobs:
       - name: Checkout latest code
         uses: actions/checkout@v2
 
-      - name: Set up JDK 16
+      - name: Set up JDK 17
         uses: actions/setup-java@v2
         with:
-          distribution: 'adopt'
+          distribution: 'temurin'
-          java-version: 16
+          java-version: 17
 
       - name: Setup build cache
         uses: actions/cache@v2.1.6

.github/workflows/test-publish.yml

@@ -0,0 +1,42 @@
+name: Publish API (Dev)
+
+on: [ push, pull_request ]
+
+jobs:
+  publish-release:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout latest code
+        uses: actions/checkout@v2
+
+      - name: Set outputs
+        id: vars
+        run: echo "::set-output name=sha_short::$(git rev-parse --short HEAD)"
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v2
+        with:
+          distribution: 'temurin'
+          java-version: 17
+
+      - name: Setup build cache
+        uses: actions/cache@v2.1.6
+        with:
+          path: ~/.gradle/caches
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle.kts') }}
+          restore-keys: |
+            ${{ runner.os }}-gradle-
+
+
+      - name: Publish artifact
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+        # The GITHUB_REF tag comes in the format 'refs/tags/xxx'.
+        # So if we split on '/' and take the 3rd value, we can get the release name.
+        run: |
+          NEW_VERSION=$(echo "${GITHUB_REF}" | cut -d "/" -f3)
+          echo "New version: ${{ steps.vars.outputs.sha_short }}"
+          echo "Github username: ${GITHUB_ACTOR}"
+          ./gradlew -Pversion=dev-${{ steps.vars.outputs.sha_short }} publish

.gitignore

@@ -14,6 +14,7 @@ bin/
 # Gradle
 .gradle
 **/build/
+**/out/
 !eco-api/src/**/build/
 .gradletasknamecache
 !gradle-wrapper.jar

CONTRIBUTING.md

@@ -1,27 +1,38 @@
 # How to contribute to eco
 
 ## Codestyle
+
 1. The eco checkstyle is in /config/checkstyle.xml
+
 - The pull request must not have any checkstyle issues.
 - Every method and field must have a javadoc attached.
 
-2. Use lombok wherever possible.
+2. Use JetBrains annotations
-- @Getter, @Setter, @UtilityClass only.
 
-3. Use JetBrains annotations
 - Every parameter should be annotated with @NotNull or @Nullable
-- Use @NotNull over lombok @NonNull
 
-4. Imports
+3. Imports
+
 - No group (*) imports.
 - No static imports.
 
+4. Kotlin
+
+- Kotlin should be the only language used in the backend, java should be the only language used in the frontend.
+- Kotlin API extensions should only be for creating extension functions and extra niceties that aren't possible in java.
+  Do not write API components in kotlin.
+- Kotlin code should never be called directly from the frontend Java API. Kotlin API extensions should always rely on
+  java, not the other way round.
+
 ## Dependency Injection
+
 - eco uses Dependency Injection
-- Any calls to AbstractEcoPlugin#getInstance are code smells and should never be used unless **absolutely necessary**.
+- Any calls to Eco#getHandler#getEcoPlugin are code smells and should never be used unless **absolutely necessary**.
 - NamespacedKeys, FixedMetadataValues, Runnables, and Schedules should be managed using AbstractEcoPlugin through DI.
-- Any DI class should extend PluginDependent where possible. If the class extends another, then you **must** store the plugin instance in a private final variable called **plugin** with a private or protected getter.
+- Any DI class should extend PluginDependent where possible. If the class extends another, then you **must** store the
+  plugin instance in a private final variable called **plugin** with a private or protected getter.
 
 ## Other
+
 - All drops **must** be sent through a DropQueue - calls to World#dropItem will get your PR rejected.
-- eco is built with java 16.
+- eco is built with java 17.

README.md

@@ -1,22 +1,45 @@
-<h1 align="center">
+# eco
-  <br>
+eco is a powerful Spigot development library that simplifies the process of plugin creation and supercharges
-  <img src="https://i.imgur.com/p5uR2Qp.png" alt="eco logo" width="256">
+your plugins.
-  <br>
+It's the engine behind [EcoEnchants](https://polymart.org/resource/490), [Reforges](https://polymart.org/resource/1330),
-</h1>
+[EcoItems](https://polymart.org/resource/1247), [EcoSkills](https://polymart.org/resource/1351),
+[EcoArmor](https://polymart.org/resource/687), [Talismans](https://polymart.org/resource/611),
+and many more.
 
-<h4 align="center">eco - Simplify spigot development.</h4>
+<p>
+    <a href="https://github.com/Auxilor/eco/releases">
+        <img alt="spigot" src="https://img.shields.io/github/v/release/Auxilor/eco?color=informational"/>
+    </a>
+    <a href="https://bstats.org/plugin/bukkit/EcoEnchants" alt="bstats servers">
+        <img src="https://img.shields.io/bstats/servers/7666?color=informational"/>
+    </a>
+    <a href="https://bstats.org/plugin/bukkit/EcoEnchants" alt="bstats players">
+        <img src="https://img.shields.io/bstats/players/7666?color=informational"/>
+    </a>
+    <a href="https://plugins.auxilor.io/" alt="Docs (gitbook)">
+        <img src="https://img.shields.io/badge/docs-gitbook-informational"/>
+    </a>
+    <a href="https://discord.gg/ZcwpSsE/" alt="Discord">
+        <img src="https://img.shields.io/discord/452518336627081236?label=discord&color=informational"/>
+    </a>
+    <a href="https://github.com/Auxilor/eco/actions/workflows/java-ci.yml" alt="Latest Dev Build">
+        <img src="https://img.shields.io/github/workflow/status/Auxilor/eco/Java%20CI/develop?color=informational"/>
+    </a>
+</p>
 
-### Plugin Information
+# For server owners
 - Requires ProtocolLib to be installed: get the latest version [here](https://www.spigotmc.org/resources/protocollib.1997/)
 - Supports 1.16.5+
 
-### bStats
+## Downloads
-<img src="https://bstats.org/signatures/bukkit/eco.svg" width="512">
 
-# Information for development
+- Stable (Recommended): [GitHub](https://github.com/Auxilor/eco/releases), [Polymart](https://polymart.org/resource/eco.773)
+- Dev (Not Recommended): [GitHub](https://github.com/Auxilor/eco/actions/workflows/java-ci.yml) (Open latest run and download)
+
+# For developers
 
 ## Javadoc
-The 6.0.0 Javadoc can be found [here](https://javadoc.jitpack.io/com/willfp/eco/6.0.0/javadoc/)
+The 6.13.0 Javadoc can be found [here](https://javadoc.jitpack.io/com/willfp/eco/6.13.0/javadoc/)
 
 ## Plugin Information
 
@@ -28,13 +51,6 @@ depend:
   - eco
 ```
 
-eco is available from any of these places:
-
-- [GitHub](https://github.com/Auxilor/eco/releases)
-- [Spigot](https://www.spigotmc.org/resources/eco.87955/)
-- [Polymart](https://polymart.org/resource/eco.773)
-- [Build it locally](https://github.com/Auxilor/eco#build-locally).
-
 ## Get from JitPack:
 
 Gradle:
@@ -52,7 +68,7 @@ dependencies {
 }
 ```
 
-Replace `Tag` with a release tag for eco, eg `6.0.0`.
+Replace `Tag` with a release tag for eco, eg `6.13.0`.
 
 Maven:
 
@@ -72,7 +88,7 @@ Maven:
 </dependency>
 ```
 
-Replace `Tag` with a release tag for eco, eg `6.0.0`.
+Replace `Tag` with a release tag for eco, eg `6.13.0`.
 
 ## Build locally:
 
@@ -85,81 +101,21 @@ cd eco
 ./gradlew build
 ```
 
-# Features
-
-Here's a list of some (not all) of the features of eco:
-
-- Command system with subcommands
-- Reworked config system
-- JSON Config Support
-- Client-Side item display
-- World drop system
-- Event manager
-    - PlayerJumpEvent
-    - ArmorEquipEvent
-    - EntityDeathByEntityEvent
-    - NaturalExpGainEvent
-- Plugin extensions (Plugins for plugins)
-- GUI System
-- Integration system for external plugins
-    - Anticheat support
-        - AAC
-        - Matrix
-        - NCP
-        - Spartan
-        - Vulcan
-    - Antigrief/Combat support
-        - CombatLogX (V10 + V11)
-        - FactionsUUID
-        - GriefPrevention
-        - Kingdoms
-        - Lands
-        - Towny
-        - WorldGuard
-    - mcMMO support
-    - Custom Items support
-        - Oraxen
-    - PlaceholderAPI support
-- NMS Proxy / Wrapper system built in
-- Custom Items system
-- Crafting Recipe handler
-- Tuples
-- Support uploading to / downloading from hastebin
-- Packet System (via ProtocolLib)
-- Dependency Injection systems
-- Prerequisite system
-- API additions (via utility classes)
-    - Get bow from arrow
-    - Break a block as a player
-    - Get a vein of blocks
-    - Create 2D lists
-    - Create NamespacedKeys safely
-    - Random number, distribution, roman numerals
-    - Set skull texture
-    - Format all strings
-        - Hex Support
-        - Gradient Support
-        - Placeholder Support
-    - Get a scoreboard team from any color
-    - Telekinesis (Drops straight to inventory) system
-    - More vector options
-- Update checker
-- bStats integration
-- Reworked systems for:
-    - NamespacedKey
-    - MetadataValue
-    - Runnables / Scheduling
-
-... and a lot more!
-
 ## License
 
 *Click here to read [the entire license](https://github.com/Auxilor/eco/blob/master/LICENSE.md).*
 
 <h1 align="center">
+  Check out our partners!
   <br>
+  <div style="width: 50%; margin: 0 auto;">
+  <br>
+    <a href="https://gamersupps.gg/discount/Auxilor?afmc=Auxilor" target="_blank">
+      <img src="https://i.imgur.com/7mFhlQO.png" alt="supps banner">
+    </a>
     <a href="https://dedimc.promo/Auxilor" target="_blank">
-      <img src="https://i.imgur.com/zdDLhFA.png" alt="dedimc banner">
+      <img src="https://i.imgur.com/x9aeH38.png" alt="dedimc banner">
     </a>
   <br>
+  </div>
 </h1>

build.gradle

@@ -1,103 +0,0 @@
-plugins {
-    id 'java-library'
-    id 'com.github.johnrengelman.shadow' version '7.0.0'
-    id 'maven-publish'
-    id 'java'
-}
-
-dependencies {
-    implementation project(":eco-api")
-    implementation project(":eco-core").getSubprojects()
-}
-
-allprojects {
-    apply plugin: 'java'
-    apply plugin: 'java-library'
-    apply plugin: 'maven-publish'
-    apply plugin: 'com.github.johnrengelman.shadow'
-
-    repositories {
-        mavenCentral()
-        mavenLocal()
-        maven { url 'https://jitpack.io' }
-
-        // NMS (for jitpack compilation)
-        maven { url 'https://repo.codemc.org/repository/nms/' }
-
-        // bStats, mcMMO
-        maven { url 'https://repo.codemc.org/repository/maven-public' }
-
-        // Spigot API
-        maven { url 'https://hub.spigotmc.org/nexus/content/repositories/snapshots/' }
-
-        // PlaceholderAPI
-        maven { url 'https://repo.extendedclip.com/content/repositories/placeholderapi/' }
-
-        // ProtocolLib
-        maven { url 'https://repo.dmulloy2.net/nexus/repository/public/' }
-
-        // WorldGuard
-        maven { url 'https://maven.enginehub.org/repo/' }
-
-        // FactionsUUID
-        maven { url 'https://ci.ender.zone/plugin/repository/everything/' }
-
-        // NoCheatPlus
-        maven { url 'https://repo.md-5.net/content/repositories/snapshots/' }
-
-        // CombatLogX
-        maven { url 'https://nexus.sirblobman.xyz/repository/public/' }
-    }
-
-    dependencies {
-        compileOnly 'org.jetbrains:annotations:19.0.0'
-
-        // Lombok
-        compileOnly 'org.projectlombok:lombok:1.18.20'
-        annotationProcessor 'org.projectlombok:lombok:1.18.20'
-        testCompileOnly 'org.projectlombok:lombok:1.18.20'
-        testAnnotationProcessor 'org.projectlombok:lombok:1.18.20'
-    }
-
-    tasks.withType(JavaCompile) {
-        options.deprecation = true
-        options.encoding = 'UTF-8'
-    }
-
-    configurations.all {
-        exclude group: "org.codehaus.plexus", module: "plexus-utils"
-        exclude group: "com.mojang", module: "brigadier"
-        exclude group: "org.kitteh", module: "paste-gg-api"
-        exclude group: "org.kitteh", module: "pastegg"
-        exclude group: "org.spongepowered", module: "configurate-hocon"
-        exclude group: "com.darkblade12", module: "particleeffect"
-        exclude group: "com.github.cryptomorin", module: "XSeries"
-    }
-
-    shadowJar {
-        relocate('org.bstats.bukkit', 'com.willfp.eco.shaded.bstats')
-    }
-
-    jar {
-        onlyIf { !sourceSets.main.allSource.files.isEmpty() }
-    }
-
-    compileJava {
-        onlyIf { !sourceSets.main.allSource.files.isEmpty() }
-    }
-
-    java {
-        sourceCompatibility = JavaVersion.VERSION_16
-        targetCompatibility = JavaVersion.VERSION_16
-        withSourcesJar()
-    }
-
-    compileJava.options.encoding = 'UTF-8'
-    compileJava.dependsOn clean
-
-    build.dependsOn shadowJar
-}
-
-group = 'com.willfp'
-archivesBaseName = project.name
-version = findProperty("version")

build.gradle.kts

@@ -0,0 +1,160 @@
+buildscript {
+    repositories {
+        mavenCentral()
+    }
+
+    dependencies {
+        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:1.6.10")
+    }
+}
+
+plugins {
+    id("java-library")
+    id("com.github.johnrengelman.shadow") version "7.1.0"
+    id("maven-publish")
+    id("java")
+    kotlin("jvm") version "1.6.10"
+}
+
+dependencies {
+    implementation(project(":eco-api"))
+    implementation(project(":eco-core:core-plugin"))
+    implementation(project(":eco-core:core-proxy"))
+    implementation(project(":eco-core:core-backend"))
+    implementation(project(":eco-core:core-nms:v1_16_R3"))
+    implementation(project(path = ":eco-core:core-nms:v1_17_R1", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_18_R1", configuration = "reobf"))
+}
+
+allprojects {
+    apply(plugin = "java")
+    apply(plugin = "java-library")
+    apply(plugin = "maven-publish")
+    apply(plugin = "com.github.johnrengelman.shadow")
+    apply(plugin = "kotlin")
+
+    repositories {
+        mavenCentral()
+        mavenLocal()
+        maven("https://jitpack.io")
+
+        // CustomCrafting
+        maven("https://maven.wolfyscript.com/repository/public/")
+
+        // SuperiorSkyblock2
+        maven("https://repo.bg-software.com/repository/api/")
+
+        // NMS (for jitpack compilation)
+        maven("https://repo.codemc.org/repository/nms/")
+
+        // mcMMO, BentoBox
+        maven("https://repo.codemc.org/repository/maven-public/")
+
+        // Spigot API, Bungee API
+        maven("https://hub.spigotmc.org/nexus/content/repositories/snapshots/")
+
+        // PlaceholderAPI
+        maven("https://repo.extendedclip.com/content/repositories/placeholderapi/")
+
+        // ProtocolLib
+        maven("https://repo.dmulloy2.net/nexus/repository/public/")
+
+        // WorldGuard
+        maven("https://maven.enginehub.org/repo/")
+
+        // FactionsUUID
+        maven("https://ci.ender.zone/plugin/repository/everything/")
+
+        // NoCheatPlus
+        maven("https://repo.md-5.net/content/repositories/snapshots/")
+
+        // CombatLogX
+        maven("https://nexus.sirblobman.xyz/repository/public/")
+
+        // IridiumSkyblock
+        maven("https://nexus.iridiumdevelopment.net/repository/maven-releases/")
+
+        // MythicMobs
+        maven("https://mvn.lumine.io/repository/maven-public/")
+
+        // Crunch
+        maven("https://redempt.dev")
+
+        // LibsDisguises
+        maven("https://repo.md-5.net/content/groups/public/")
+    }
+
+    dependencies {
+        compileOnly(kotlin("stdlib", version = "1.6.10"))
+        compileOnly("org.jetbrains:annotations:23.0.0")
+
+        // Test
+        testImplementation("org.junit.jupiter:junit-jupiter-api:5.8.2")
+        testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.8.2")
+        
+        // Adventure
+        compileOnly("net.kyori:adventure-api:4.9.3")
+        compileOnly("net.kyori:adventure-text-serializer-gson:4.9.3")
+        compileOnly("net.kyori:adventure-text-serializer-legacy:4.9.3")
+
+        // Other
+        compileOnly("com.google.guava:guava:31.0.1-jre")
+        compileOnly("com.github.ben-manes.caffeine:caffeine:3.0.5")
+    }
+
+    tasks.withType<JavaCompile> {
+        options.encoding = "UTF-8"
+    }
+
+    configurations.all {
+        exclude(group = "org.codehaus.plexus", module = "plexus-utils")
+        exclude(group = "com.mojang", module = "brigadier")
+        exclude(group = "org.kitteh", module = "paste-gg-api")
+        exclude(group = "org.kitteh", module = "pastegg")
+        exclude(group = "org.spongepowered", module = "configurate-hocon")
+        exclude(group = "com.darkblade12", module = "particleeffect")
+        exclude(group = "com.github.cryptomorin", module = "XSeries")
+    }
+
+    tasks {
+        compileKotlin {
+            kotlinOptions {
+                jvmTarget = "17"
+            }
+            targetCompatibility = "17"
+            sourceCompatibility = "17"
+        }
+
+        shadowJar {
+            relocate("org.bstats", "com.willfp.eco.shaded.bstats")
+            relocate("net.kyori.adventure.text.minimessage", "com.willfp.eco.shaded.minimessage")
+        }
+
+        compileJava {
+            dependsOn(clean)
+            options.encoding = "UTF-8"
+        }
+
+        java {
+            sourceCompatibility = JavaVersion.VERSION_17
+            targetCompatibility = JavaVersion.VERSION_17
+            withSourcesJar()
+        }
+
+        test {
+            useJUnitPlatform()
+
+            // Show test results.
+            testLogging {
+                events("passed", "skipped", "failed")
+            }
+        }
+
+        build {
+            dependsOn(shadowJar)
+        }
+    }
+}
+
+group = "com.willfp"
+version = findProperty("version")!!

config/checkstyle/checkstyle.xml

@@ -32,10 +32,6 @@
 -->
 
 <module name="Checker">
-    <module name="SuppressionFilter">
-        <property name="file" value="config/checkstyle/suppression.xml"/>
-    </module>
-
     <!--
         If you set the basedir property below, then all reported file
         names will be relative to the specified directory. See
@@ -45,7 +41,7 @@
     -->
     <property name="severity" value="error"/>
 
-    <property name="fileExtensions" value="java, properties, xml"/>
+    <property name="fileExtensions" value="java, properties, xml, kt"/>
 
     <!-- Excludes all 'module-info.java' files              -->
     <!-- See https://checkstyle.org/config_filefilters.html -->
@@ -66,6 +62,7 @@
     <module name="FileLength"/>
     <module name="LineLength">
         <property name="fileExtensions" value="java"/>
+        <property name="fileExtensions" value="kt"/>
         <property name="max" value="200"/>
     </module>
 

config/checkstyle/suppression.xml

@@ -1,24 +0,0 @@
-<?xml version="1.0"?>
-
-<!DOCTYPE suppressions PUBLIC
-        "-//Puppy Crawl//DTD Suppressions 1.1//EN"
-        "http://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
-
-<suppressions>
-    <!-- Internals don't need javadoc. -->
-    <suppress files="[\\/]internal[\\/]" checks="MissingJavadocMethod"/>
-    <suppress files="[\\/]internal[\\/]" checks="JavadocVariable"/>
-    <suppress files="[\\/]eco[\\/]spigot[\\/]" checks="MissingJavadocMethod"/>
-    <suppress files="[\\/]eco[\\/]spigot[\\/]" checks="JavadocVariable"/>
-    <suppress files="[\\/]eco[\\/]proxy[\\/]" checks="MissingJavadocMethod"/>
-    <suppress files="[\\/]eco[\\/]proxy[\\/]" checks="JavadocVariable"/>
-
-    <!-- Modified version of library -->
-    <suppress files="ArmorEquipEvent.java" checks="JavadocVariable"/>
-    <suppress files="ArmorEquipEvent.java" checks="MissingJavadocMethod"/>
-    <suppress files="ArmorEquipEvent.java" checks="JavadocStyle"/>
-    <suppress files="ArmorListener.java" checks="JavadocVariable"/>
-    <suppress files="ArmorListener.java" checks="MissingJavadocMethod"/>
-    <suppress files="ArmorType.java" checks="JavadocVariable"/>
-    <suppress files="ArmorType.java" checks="MissingJavadocMethod"/>
-</suppressions>

eco-api/build.gradle

@@ -1,25 +1,18 @@
-plugins {
+dependencies {
-    id 'com.github.johnrengelman.shadow'
+    // Adventure
+    compileOnly 'net.kyori:adventure-platform-bukkit:4.0.0'
+    compileOnly 'net.kyori:adventure-text-minimessage:4.1.0-SNAPSHOT'
+
+    // Other
+    compileOnly 'org.spigotmc:spigot-api:1.17.1-R0.1-SNAPSHOT'
+    compileOnly 'org.apache.maven:maven-artifact:3.8.1'
+    compileOnly 'com.comphenix.protocol:ProtocolLib:4.6.1-SNAPSHOT'
+    compileOnly 'com.google.code.gson:gson:2.8.8'
 }
 
 group 'com.willfp'
 version rootProject.version
 
-dependencies {
-    compileOnly 'org.spigotmc:spigot-api:1.17-R0.1-SNAPSHOT'
-    compileOnly 'org.apache.maven:maven-artifact:3.0.3'
-    compileOnly 'org.bstats:bstats-bukkit:1.7'
-    compileOnly 'com.comphenix.protocol:ProtocolLib:4.6.0-SNAPSHOT'
-    compileOnly 'com.google.code.gson:gson:2.8.7'
-}
-
-java {
-    withJavadocJar()
-}
-
-compileJava.options.encoding = 'UTF-8'
-compileJava.dependsOn clean
-
 build.dependsOn publishToMavenLocal
 
 publishing {

eco-api/src/main/java/com/willfp/eco/core/AbstractPacketAdapter.java

@@ -6,7 +6,6 @@ import com.comphenix.protocol.events.ListenerPriority;
 import com.comphenix.protocol.events.PacketAdapter;
 import com.comphenix.protocol.events.PacketContainer;
 import com.comphenix.protocol.events.PacketEvent;
-import lombok.Getter;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 
@@ -26,7 +25,6 @@ public abstract class AbstractPacketAdapter extends PacketAdapter {
      * <p>
      * Useful for monitor priority adapters that <b>must</b> be ran last.
      */
-    @Getter
     private final boolean postLoad;
 
     /**
@@ -134,4 +132,13 @@ public abstract class AbstractPacketAdapter extends PacketAdapter {
             ProtocolLibrary.getProtocolManager().addPacketListener(this);
         }
     }
+
+    /**
+     * Get if the packet adapter should be loaded last.
+     *
+     * @return If post load.
+     */
+    public boolean isPostLoad() {
+        return this.postLoad;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/Eco.java

@@ -1,30 +1,29 @@
 package com.willfp.eco.core;
 
-import lombok.Getter;
-import lombok.experimental.UtilityClass;
 import org.apache.commons.lang.Validate;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
 /**
- * Base class to hold the handler.
+ * Holds the instance of the eco handler for bridging between the frontend
+ * and backend.
  *
+ * @see Eco#getHandler()
  * @see Handler
  */
-@UtilityClass
+@ApiStatus.Internal
-public class Eco {
+public final class Eco {
     /**
      * Instance of eco handler.
-     * <p>
-     * The handler is, in essence, a way to interface between the eco-api
-     * frontend module, and the eco-backend implementations.
-     * <p>
-     * There shouldn't really be any reason to ever use the handler
-     * in your own plugins, but if you want to then you can - it's
-     * just a part of the API like any other.
      */
-    @Getter
+    @ApiStatus.Internal
-    private Handler handler;
+    private static Handler handler;
 
     /**
      * Set the handler.
@@ -32,9 +31,52 @@ public class Eco {
      * @param handler The handler.
      */
     @ApiStatus.Internal
-    public void setHandler(@NotNull final Handler handler) {
+    public static void setHandler(@NotNull final Handler handler) {
         Validate.isTrue(Eco.handler == null, "Already initialized!");
 
         Eco.handler = handler;
     }
+
+    /**
+     * Get the instance of the eco handler; the bridge between the api frontend
+     * and the implementation backend.
+     * <p>
+     * <strong>Do not use the handler in your plugins!</strong> It can and will contain
+     * breaking changes between minor versions and even patches, and you will create
+     * compatibility issues by using the handler. All parts of the handler have been abstracted
+     * into logically named API components that you can use.
+     * <p>
+     * Prior to version 6.12.0, the handler was considered as an API component, but it has
+     * since been moved into an internal component, and in 6.17.0, the first breaking change
+     * was introduced to {@link com.willfp.eco.core.config.wrapper.ConfigFactory}. This means
+     * that any usages of the handler can now cause problems in your plugins.
+     *
+     * @return The handler.
+     */
+    @ApiStatus.Internal
+    public static Handler getHandler() {
+        return handler;
+    }
+
+    /**
+     * Eco Handler components are internals, so if a class is marked as a handler component,
+     * then it should be treated the same as if it was marked with {@link ApiStatus.Internal}.
+     * <p>
+     * If a class is marked with {@link HandlerComponent}, <strong>Do not reference it in
+     * your code!</strong> It can and will contain breaking changes between minor versions and
+     * even patches, and you will create compatibility issues by using them.
+     * <p>
+     * Handler components should also be marked with {@link ApiStatus.Internal} in order to
+     * cause compiler / IDE warnings.
+     */
+    @Documented
+    @Retention(RetentionPolicy.CLASS)
+    @Target({ElementType.TYPE})
+    public @interface HandlerComponent {
+
+    }
+
+    private Eco() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/EcoPlugin.java

@@ -7,20 +7,18 @@ import com.willfp.eco.core.config.updating.ConfigHandler;
 import com.willfp.eco.core.display.Display;
 import com.willfp.eco.core.display.DisplayModule;
 import com.willfp.eco.core.events.EventManager;
+import com.willfp.eco.core.extensions.Extension;
 import com.willfp.eco.core.extensions.ExtensionLoader;
 import com.willfp.eco.core.factory.MetadataValueFactory;
 import com.willfp.eco.core.factory.NamespacedKeyFactory;
 import com.willfp.eco.core.factory.RunnableFactory;
 import com.willfp.eco.core.integrations.IntegrationLoader;
 import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
-import com.willfp.eco.core.proxy.AbstractProxy;
 import com.willfp.eco.core.proxy.ProxyFactory;
 import com.willfp.eco.core.scheduling.Scheduler;
 import com.willfp.eco.core.web.UpdateChecker;
-import lombok.Getter;
 import org.apache.commons.lang.Validate;
 import org.apache.maven.artifact.versioning.DefaultArtifactVersion;
-import org.bstats.bukkit.Metrics;
 import org.bukkit.Bukkit;
 import org.bukkit.configuration.file.FileConfiguration;
 import org.bukkit.event.Listener;
@@ -33,6 +31,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Objects;
 import java.util.Set;
 import java.util.logging.Logger;
 import java.util.stream.Collectors;
@@ -52,77 +51,66 @@ import java.util.stream.Collectors;
  * <b>IMPORTANT: When reloading a plugin, all runnables / tasks will
  * be cancelled.</b>
  */
-public abstract class EcoPlugin extends JavaPlugin {
+@SuppressWarnings("unused")
+public abstract class EcoPlugin extends JavaPlugin implements PluginLike {
     /**
-     * The spigot resource ID of the plugin.
+     * The polymart resource ID of the plugin.
      */
-    @Getter
     private final int resourceId;
 
     /**
      * The bStats resource ID of the plugin.
      */
-    @Getter
     private final int bStatsId;
 
     /**
      * The package where proxy implementations are.
      */
-    @Getter
     private final String proxyPackage;
 
     /**
      * The color of the plugin, used in messages.
      */
-    @Getter
     private final String color;
 
     /**
      * Loaded integrations.
      */
-    @Getter
     private final Set<String> loadedIntegrations = new HashSet<>();
 
     /**
      * The internal plugin scheduler.
      */
-    @Getter
     private final Scheduler scheduler;
 
     /**
      * The internal plugin Event Manager.
      */
-    @Getter
     private final EventManager eventManager;
 
     /**
      * Config.yml.
      */
-    @Getter
     private final ConfigYml configYml;
 
     /**
      * Lang.yml.
      */
-    @Getter
     private final LangYml langYml;
 
     /**
      * The internal factory to produce {@link org.bukkit.NamespacedKey}s.
      */
-    @Getter
     private final NamespacedKeyFactory namespacedKeyFactory;
 
     /**
      * The internal factory to produce {@link org.bukkit.metadata.FixedMetadataValue}s.
      */
-    @Getter
     private final MetadataValueFactory metadataValueFactory;
 
     /**
      * The internal factory to produce {@link com.willfp.eco.core.scheduling.RunnableTask}s.
      */
-    @Getter
     private final RunnableFactory runnableFactory;
 
     /**
@@ -130,19 +118,16 @@ public abstract class EcoPlugin extends JavaPlugin {
      *
      * @see com.willfp.eco.core.extensions.Extension
      */
-    @Getter
     private final ExtensionLoader extensionLoader;
 
     /**
      * The handler class for updatable classes.
      */
-    @Getter
     private final ConfigHandler configHandler;
 
     /**
      * The display module for the plugin.
      */
-    @Getter
     private DisplayModule displayModule;
 
     /**
@@ -153,30 +138,32 @@ public abstract class EcoPlugin extends JavaPlugin {
     /**
      * If the server is running an outdated version of the plugin.
      */
-    @Getter
     private boolean outdated = false;
 
     /**
      * If the plugin supports extensions.
      */
-    @Getter
     private final boolean supportingExtensions;
 
     /**
      * The proxy factory.
      */
-    @Getter
+    @Nullable
     private final ProxyFactory proxyFactory;
 
     /**
-     * Create a new plugin without a specified color, proxy support, spigot, or bStats.
+     * Create a new plugin.
+     * <p>
+     * Will read from eco.yml (like plugin.yml) to fetch values that would otherwise be passed
+     * into the constructor. If no eco.yml is present, the plugin will load without extension
+     * support, without proxy support, with no update-checker or bStats, and with the color white.
      */
     protected EcoPlugin() {
-        this("&f");
+        this((PluginProps) null);
     }
 
     /**
-     * Create a new plugin without proxy support, spigot, or bStats.
+     * Create a new plugin without proxy support, polymart, or bStats.
      *
      * @param color The color.
      */
@@ -186,7 +173,7 @@ public abstract class EcoPlugin extends JavaPlugin {
 
 
     /**
-     * Create a new plugin unlinked to spigot and bStats.
+     * Create a new plugin unlinked to polymart and bStats.
      *
      * @param proxyPackage The package where proxy implementations are stored.
      * @param color        The color of the plugin (used in messages, using standard formatting)
@@ -199,7 +186,7 @@ public abstract class EcoPlugin extends JavaPlugin {
     /**
      * Create a new plugin without proxy or extension support.
      *
-     * @param resourceId The spigot resource ID for the plugin.
+     * @param resourceId The polymart resource ID for the plugin.
      * @param bStatsId   The bStats resource ID for the plugin.
      * @param color      The color of the plugin (used in messages, using standard formatting)
      */
@@ -212,7 +199,7 @@ public abstract class EcoPlugin extends JavaPlugin {
     /**
      * Create a new plugin without proxy support.
      *
-     * @param resourceId           The spigot resource ID for the plugin.
+     * @param resourceId           The polymart resource ID for the plugin.
      * @param bStatsId             The bStats resource ID for the plugin.
      * @param color                The color of the plugin (used in messages, using standard formatting)
      * @param supportingExtensions If the plugin supports extensions.
@@ -227,7 +214,7 @@ public abstract class EcoPlugin extends JavaPlugin {
     /**
      * Create a new plugin without extension support.
      *
-     * @param resourceId   The spigot resource ID for the plugin.
+     * @param resourceId   The polymart resource ID for the plugin.
      * @param bStatsId     The bStats resource ID for the plugin.
      * @param proxyPackage The package where proxy implementations are stored.
      * @param color        The color of the plugin (used in messages, using standard formatting)
@@ -242,7 +229,7 @@ public abstract class EcoPlugin extends JavaPlugin {
     /**
      * Create a new plugin.
      *
-     * @param resourceId           The spigot resource ID for the plugin.
+     * @param resourceId           The polymart resource ID for the plugin.
      * @param bStatsId             The bStats resource ID for the plugin.
      * @param proxyPackage         The package where proxy implementations are stored.
      * @param color                The color of the plugin (used in messages, using standard formatting)
@@ -253,6 +240,23 @@ public abstract class EcoPlugin extends JavaPlugin {
                         @NotNull final String proxyPackage,
                         @NotNull final String color,
                         final boolean supportingExtensions) {
+        this(
+                PluginProps.createSimple(
+                        resourceId,
+                        bStatsId,
+                        proxyPackage,
+                        color,
+                        supportingExtensions
+                )
+        );
+    }
+
+    /**
+     * Create a new plugin.
+     *
+     * @param pluginProps The props. If left null, it will read from eco.yml.
+     */
+    protected EcoPlugin(@Nullable final PluginProps pluginProps) {
         /*
         The handler must be initialized before any plugin's constructors
         are called, as the constructors call Eco#getHandler().
@@ -270,15 +274,15 @@ public abstract class EcoPlugin extends JavaPlugin {
         a standalone handler class, but then there would be an interface
         left in the API that doesn't really help anything.
 
-        The other alternative would be do use reflection to get a 'createHandler'
+        The other alternative would be to use reflection to get a 'createHandler'
-        method that only exists in EcoSpigotPlugin - but that feels really dirty
+        method that only exists in EcoSpigotPlugin - but that feels filthy,
         and I'd rather only use reflection where necessary.
         */
 
         if (Eco.getHandler() == null && this instanceof Handler) {
             /*
             This code is only ever called by EcoSpigotPlugin (EcoHandler)
-            as it's the first plugin to load and it is a handler.
+            as it's the first plugin to load, and it is a handler.
 
             Any other plugins will never call this code as the handler
             will have already been initialized.
@@ -289,11 +293,16 @@ public abstract class EcoPlugin extends JavaPlugin {
 
         assert Eco.getHandler() != null;
 
-        this.resourceId = resourceId;
+        PluginProps generatedProps = Eco.getHandler().getProps(pluginProps, this.getClass());
-        this.bStatsId = bStatsId;
+        generatedProps.validate();
-        this.proxyPackage = proxyPackage;
+        PluginProps props = this.mutateProps(generatedProps);
-        this.color = color;
+        props.validate();
-        this.supportingExtensions = supportingExtensions;
+
+        this.resourceId = props.getResourceId();
+        this.bStatsId = props.getBStatsId();
+        this.proxyPackage = props.getProxyPackage();
+        this.color = props.getColor();
+        this.supportingExtensions = props.isSupportingExtensions();
 
         this.scheduler = Eco.getHandler().createScheduler(this);
         this.eventManager = Eco.getHandler().createEventManager(this);
@@ -305,10 +314,27 @@ public abstract class EcoPlugin extends JavaPlugin {
         this.logger = Eco.getHandler().createLogger(this);
         this.proxyFactory = this.proxyPackage.equalsIgnoreCase("") ? null : Eco.getHandler().createProxyFactory(this);
 
-        this.langYml = new LangYml(this);
+        this.langYml = this.createLangYml();
-        this.configYml = new ConfigYml(this);
+        this.configYml = this.createConfigYml();
 
         Eco.getHandler().addNewPlugin(this);
+
+        /*
+        The minimum eco version check was moved here because it's very common
+        to add a lot of code in the constructor of plugins; meaning that the plugin
+        can throw errors without it being obvious to the user that the reason is that
+        they have an outdated version of eco installed.
+         */
+
+        DefaultArtifactVersion runningVersion = new DefaultArtifactVersion(Eco.getHandler().getEcoPlugin().getDescription().getVersion());
+        DefaultArtifactVersion requiredVersion = new DefaultArtifactVersion(this.getMinimumEcoVersion());
+        if (!(runningVersion.compareTo(requiredVersion) > 0 || runningVersion.equals(requiredVersion))) {
+            this.getLogger().severe("You are running an outdated version of eco!");
+            this.getLogger().severe("You must be on at least" + this.getMinimumEcoVersion());
+            this.getLogger().severe("Download the newest version here:");
+            this.getLogger().severe("https://polymart.org/download/773/recent/JSpprMspkuyecf5y1wQ2Jn8OoLQSQ_IW");
+            Bukkit.getPluginManager().disablePlugin(this);
+        }
     }
 
     /**
@@ -327,38 +353,29 @@ public abstract class EcoPlugin extends JavaPlugin {
                 DefaultArtifactVersion mostRecentVersion = new DefaultArtifactVersion(version);
                 if (!(currentVersion.compareTo(mostRecentVersion) > 0 || currentVersion.equals(mostRecentVersion))) {
                     this.outdated = true;
-                    this.getScheduler().runTimer(() -> {
+                    this.getLogger().warning("&c" + this.getName() + " is out of date! (Version " + this.getDescription().getVersion() + ")");
-                        this.getLogger().info("&c " + this.getName() + " is out of date! (Version " + this.getDescription().getVersion() + ")");
+                    this.getLogger().warning("&cThe newest version is &f" + version);
-                        this.getLogger().info("&cThe newest version is &f" + version);
+                    this.getLogger().warning("&cDownload the new version!");
-                        this.getLogger().info("&cDownload the new version!");
-                    }, 0, 864000);
                 }
             });
         }
 
-        DefaultArtifactVersion runningVersion = new DefaultArtifactVersion(Eco.getHandler().getEcoPlugin().getDescription().getVersion());
-        DefaultArtifactVersion requiredVersion = new DefaultArtifactVersion(this.getMinimumEcoVersion());
-        if (!(runningVersion.compareTo(requiredVersion) > 0 || runningVersion.equals(requiredVersion))) {
-            this.getLogger().severe("You are running an outdated version of eco!");
-            this.getLogger().severe("You must be on at least" + this.getMinimumEcoVersion());
-            this.getLogger().severe("Download the newest version here:");
-            this.getLogger().severe("https://polymart.org/download/773/recent/JSpprMspkuyecf5y1wQ2Jn8OoLQSQ_IW");
-            Bukkit.getPluginManager().disablePlugin(this);
-        }
-
         if (this.getBStatsId() != 0) {
-            new Metrics(this, this.getBStatsId());
+            Eco.getHandler().registerBStats(this);
         }
 
-        Set<String> enabledPlugins = Arrays.stream(Bukkit.getPluginManager().getPlugins()).map(Plugin::getName).collect(Collectors.toSet());
+        Set<String> enabledPlugins = Arrays.stream(Bukkit.getPluginManager().getPlugins())
+                .map(Plugin::getName)
+                .map(String::toLowerCase)
+                .collect(Collectors.toSet());
 
-        if (enabledPlugins.contains("PlaceholderAPI")) {
+        if (enabledPlugins.contains("PlaceholderAPI".toLowerCase())) {
             this.loadedIntegrations.add("PlaceholderAPI");
             PlaceholderManager.addIntegration(Eco.getHandler().createPAPIIntegration(this));
         }
 
         this.loadIntegrationLoaders().forEach((integrationLoader -> {
-            if (enabledPlugins.contains(integrationLoader.getPluginName())) {
+            if (enabledPlugins.contains(integrationLoader.getPluginName().toLowerCase())) {
                 this.loadedIntegrations.add(integrationLoader.getPluginName());
                 integrationLoader.load();
             }
@@ -405,7 +422,6 @@ public abstract class EcoPlugin extends JavaPlugin {
 
         this.getEventManager().unregisterAllListeners();
         this.getScheduler().cancelAll();
-        this.getConfigHandler().saveAllConfigs();
 
         this.handleDisable();
 
@@ -460,11 +476,15 @@ public abstract class EcoPlugin extends JavaPlugin {
 
         this.reload();
 
+        for (Extension extension : this.getExtensionLoader().getLoadedExtensions()) {
+            extension.handleAfterLoad();
+        }
+
         this.getLogger().info("Loaded " + this.color + this.getName());
     }
 
     /**
-     * Default code to be executed on plugin reload.
+     * Reload the plugin.
      */
     public final void reload() {
         this.getConfigHandler().updateConfigs();
@@ -474,6 +494,23 @@ public abstract class EcoPlugin extends JavaPlugin {
         this.getScheduler().cancelAll();
 
         this.handleReload();
+
+        for (Extension extension : this.extensionLoader.getLoadedExtensions()) {
+            extension.handleReload();
+        }
+    }
+
+    /**
+     * Reload the plugin and return the time taken to reload.
+     *
+     * @return The time.
+     */
+    public final long reloadWithTime() {
+        long startTime = System.currentTimeMillis();
+
+        this.reload();
+
+        return System.currentTimeMillis() - startTime;
     }
 
     /**
@@ -523,6 +560,21 @@ public abstract class EcoPlugin extends JavaPlugin {
 
     }
 
+    /**
+     * Mutate the plugin props.
+     * <p>
+     * Useful for eco-based plugin libraries to enforce certain properties, such as
+     * forcing extensions to be enabled.
+     * <p>
+     * Props are validated both before and after calling this method.
+     *
+     * @param props The props.
+     * @return The mutated props.
+     */
+    protected PluginProps mutateProps(@NotNull final PluginProps props) {
+        return props;
+    }
+
     /**
      * The plugin-specific integrations to be tested and loaded.
      *
@@ -559,6 +611,28 @@ public abstract class EcoPlugin extends JavaPlugin {
      */
     protected abstract List<Listener> loadListeners();
 
+    /**
+     * Useful for custom LangYml implementations.
+     * <p>
+     * Override if needed.
+     *
+     * @return lang.yml.
+     */
+    protected LangYml createLangYml() {
+        return new LangYml(this);
+    }
+
+    /**
+     * Useful for custom ConfigYml implementations.
+     * <p>
+     * Override if needed.
+     *
+     * @return config.yml.
+     */
+    protected ConfigYml createConfigYml() {
+        return new ConfigYml(this);
+    }
+
     /**
      * Create the display module for the plugin.
      *
@@ -601,8 +675,8 @@ public abstract class EcoPlugin extends JavaPlugin {
      * @param <T>        The proxy type.
      * @return The proxy.
      */
-    public <T extends AbstractProxy> T getProxy(@NotNull final Class<T> proxyClass) {
+    public final <T> T getProxy(@NotNull final Class<T> proxyClass) {
-        Validate.notNull(proxyFactory, "Plugin does not support proxy!");
+        Validate.notNull(proxyFactory, "Plugin does not support proxies!");
 
         return proxyFactory.getProxy(proxyClass);
     }
@@ -620,7 +694,7 @@ public abstract class EcoPlugin extends JavaPlugin {
     public final FileConfiguration getConfig() {
         this.getLogger().warning("Call to default config method in eco plugin!");
 
-        return this.getConfigYml().getBukkitHandle();
+        return Objects.requireNonNull(this.getConfigYml().getBukkitHandle());
     }
 
     /**
@@ -680,4 +754,168 @@ public abstract class EcoPlugin extends JavaPlugin {
     public static Set<String> getPluginNames() {
         return new HashSet<>(Eco.getHandler().getLoadedPlugins());
     }
+
+    /**
+     * Get the polymart resource ID.
+     *
+     * @return The resource ID.
+     */
+    public int getResourceId() {
+        return this.resourceId;
+    }
+
+    /**
+     * Get the bStats ID.
+     *
+     * @return The ID.
+     */
+    public int getBStatsId() {
+        return this.bStatsId;
+    }
+
+    /**
+     * Get the proxy package.
+     *
+     * @return The package where proxies are contained.
+     */
+    public String getProxyPackage() {
+        return this.proxyPackage;
+    }
+
+    /**
+     * Get the plugin color (uses legacy formatting).
+     *
+     * @return The color.
+     */
+    public String getColor() {
+        return this.color;
+    }
+
+    /**
+     * Get all loaded integration names.
+     *
+     * @return The integrations.
+     */
+    public Set<String> getLoadedIntegrations() {
+        return this.loadedIntegrations;
+    }
+
+    /**
+     * Get the scheduler.
+     *
+     * @return The scheduler.
+     */
+    public Scheduler getScheduler() {
+        return this.scheduler;
+    }
+
+    /**
+     * Get the event manager.
+     *
+     * @return The event manager.
+     */
+    public EventManager getEventManager() {
+        return this.eventManager;
+    }
+
+    /**
+     * Get config.yml.
+     *
+     * @return config.yml.
+     */
+    public ConfigYml getConfigYml() {
+        return this.configYml;
+    }
+
+    /**
+     * Get lang.yml.
+     *
+     * @return lang.yml.
+     */
+    public LangYml getLangYml() {
+        return this.langYml;
+    }
+
+    /**
+     * Get the NamespacedKey factory.
+     *
+     * @return The factory.
+     */
+    public NamespacedKeyFactory getNamespacedKeyFactory() {
+        return this.namespacedKeyFactory;
+    }
+
+    /**
+     * Get the metadata value factory.
+     *
+     * @return The factory.
+     */
+    public MetadataValueFactory getMetadataValueFactory() {
+        return this.metadataValueFactory;
+    }
+
+    /**
+     * Get the runnable factory.
+     *
+     * @return The runnable factory.
+     */
+    public RunnableFactory getRunnableFactory() {
+        return this.runnableFactory;
+    }
+
+    /**
+     * Get the extension loader.
+     *
+     * @return The extension loader.
+     */
+    public ExtensionLoader getExtensionLoader() {
+        return this.extensionLoader;
+    }
+
+    /**
+     * Get the config handler.
+     *
+     * @return The config handler.
+     */
+    public ConfigHandler getConfigHandler() {
+        return this.configHandler;
+    }
+
+    /**
+     * Get the plugin's display module.
+     *
+     * @return The display module.
+     */
+    @Nullable
+    public DisplayModule getDisplayModule() {
+        return this.displayModule;
+    }
+
+    /**
+     * Get if the plugin is outdated.
+     *
+     * @return If outdated.
+     */
+    public boolean isOutdated() {
+        return this.outdated;
+    }
+
+    /**
+     * Get if the plugin supports extensions.
+     *
+     * @return If extensions are supported.
+     */
+    public boolean isSupportingExtensions() {
+        return this.supportingExtensions;
+    }
+
+    /**
+     * Get the proxy factory.
+     *
+     * @return The proxy factory.
+     */
+    @Nullable
+    public ProxyFactory getProxyFactory() {
+        return this.proxyFactory;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/Handler.java

@@ -2,25 +2,37 @@ package com.willfp.eco.core;
 
 import com.willfp.eco.core.config.updating.ConfigHandler;
 import com.willfp.eco.core.config.wrapper.ConfigFactory;
+import com.willfp.eco.core.data.ProfileHandler;
+import com.willfp.eco.core.data.keys.KeyRegistry;
 import com.willfp.eco.core.drops.DropQueueFactory;
 import com.willfp.eco.core.events.EventManager;
 import com.willfp.eco.core.extensions.ExtensionLoader;
 import com.willfp.eco.core.factory.MetadataValueFactory;
 import com.willfp.eco.core.factory.NamespacedKeyFactory;
 import com.willfp.eco.core.factory.RunnableFactory;
+import com.willfp.eco.core.fast.FastItemStack;
 import com.willfp.eco.core.gui.GUIFactory;
 import com.willfp.eco.core.integrations.placeholder.PlaceholderIntegration;
 import com.willfp.eco.core.proxy.Cleaner;
 import com.willfp.eco.core.proxy.ProxyFactory;
 import com.willfp.eco.core.scheduling.Scheduler;
+import net.kyori.adventure.platform.bukkit.BukkitAudiences;
+import org.bukkit.Location;
+import org.bukkit.NamespacedKey;
+import org.bukkit.entity.Entity;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.List;
 import java.util.logging.Logger;
 
 /**
- * @see Eco
+ * @see Eco#getHandler()
  */
+@ApiStatus.Internal
+@SuppressWarnings("removal")
 public interface Handler {
     /**
      * Create a scheduler.
@@ -28,6 +40,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The scheduler.
      */
+    @NotNull
     Scheduler createScheduler(@NotNull EcoPlugin plugin);
 
     /**
@@ -36,6 +49,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The event manager.
      */
+    @NotNull
     EventManager createEventManager(@NotNull EcoPlugin plugin);
 
     /**
@@ -44,6 +58,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The factory.
      */
+    @NotNull
     NamespacedKeyFactory createNamespacedKeyFactory(@NotNull EcoPlugin plugin);
 
     /**
@@ -52,6 +67,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The factory.
      */
+    @NotNull
     MetadataValueFactory createMetadataValueFactory(@NotNull EcoPlugin plugin);
 
     /**
@@ -60,6 +76,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The factory.
      */
+    @NotNull
     RunnableFactory createRunnableFactory(@NotNull EcoPlugin plugin);
 
     /**
@@ -68,6 +85,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The factory.
      */
+    @NotNull
     ExtensionLoader createExtensionLoader(@NotNull EcoPlugin plugin);
 
     /**
@@ -76,6 +94,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The handler.
      */
+    @NotNull
     ConfigHandler createConfigHandler(@NotNull EcoPlugin plugin);
 
     /**
@@ -84,6 +103,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The logger.
      */
+    @NotNull
     Logger createLogger(@NotNull EcoPlugin plugin);
 
     /**
@@ -92,6 +112,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The integration.
      */
+    @NotNull
     PlaceholderIntegration createPAPIIntegration(@NotNull EcoPlugin plugin);
 
     /**
@@ -100,6 +121,7 @@ public interface Handler {
      * @param plugin The plugin.
      * @return The factory.
      */
+    @NotNull
     ProxyFactory createProxyFactory(@NotNull EcoPlugin plugin);
 
     /**
@@ -107,6 +129,7 @@ public interface Handler {
      *
      * @return The plugin.
      */
+    @NotNull
     EcoPlugin getEcoPlugin();
 
     /**
@@ -114,6 +137,7 @@ public interface Handler {
      *
      * @return The factory.
      */
+    @NotNull
     ConfigFactory getConfigFactory();
 
     /**
@@ -121,6 +145,7 @@ public interface Handler {
      *
      * @return The factory.
      */
+    @NotNull
     DropQueueFactory getDropQueueFactory();
 
     /**
@@ -128,6 +153,7 @@ public interface Handler {
      *
      * @return The factory.
      */
+    @NotNull
     GUIFactory getGUIFactory();
 
     /**
@@ -135,6 +161,7 @@ public interface Handler {
      *
      * @return The cleaner.
      */
+    @NotNull
     Cleaner getCleaner();
 
     /**
@@ -150,6 +177,7 @@ public interface Handler {
      * @param name The name.
      * @return The plugin.
      */
+    @Nullable
     EcoPlugin getPluginByName(@NotNull String name);
 
     /**
@@ -157,5 +185,90 @@ public interface Handler {
      *
      * @return A list of plugin names in lowercase.
      */
+    @NotNull
     List<String> getLoadedPlugins();
+
+    /**
+     * Create a FastItemStack.
+     *
+     * @param itemStack The base ItemStack.
+     * @return The FastItemStack.
+     */
+    @NotNull
+    FastItemStack createFastItemStack(@NotNull ItemStack itemStack);
+
+    /**
+     * Register bStats metrics.
+     *
+     * @param plugin The plugin.
+     */
+    void registerBStats(@NotNull EcoPlugin plugin);
+
+    /**
+     * Get the requirement factory.
+     *
+     * @return The factory.
+     */
+    @NotNull
+    @Deprecated(forRemoval = true)
+    com.willfp.eco.core.requirement.RequirementFactory getRequirementFactory();
+
+    /**
+     * Get Adventure audiences.
+     *
+     * @return The audiences.
+     */
+    @Nullable
+    BukkitAudiences getAdventure();
+
+    /**
+     * Get the key registry.
+     *
+     * @return The registry.
+     */
+    @NotNull
+    KeyRegistry getKeyRegistry();
+
+    /**
+     * Get the PlayerProfile handler.
+     *
+     * @return The handler.
+     */
+    @NotNull
+    ProfileHandler getProfileHandler();
+
+    /**
+     * Create dummy entity - never spawned, exists purely in code.
+     *
+     * @param location The location.
+     * @return The entity.
+     */
+    @NotNull
+    Entity createDummyEntity(@NotNull Location location);
+
+    /**
+     * Create a {@link NamespacedKey} quickly
+     * <p>
+     * Bypasses the constructor, allowing for the creation of invalid keys,
+     * therefore this is considered unsafe and should only be called after
+     * the key has been confirmed to be valid.
+     *
+     * @param namespace The namespace.
+     * @param key       The key.
+     * @return The key.
+     */
+    @NotNull
+    NamespacedKey createNamespacedKey(@NotNull String namespace,
+                                      @NotNull String key);
+
+    /**
+     * Return or get props for a plugin.
+     *
+     * @param existing The existing constructor props.
+     * @param plugin   The plugin.
+     * @return The props.
+     */
+    @NotNull
+    PluginProps getProps(@Nullable PluginProps existing,
+                         @NotNull Class<? extends EcoPlugin> plugin);
 }

eco-api/src/main/java/com/willfp/eco/core/PluginDependent.java

@@ -1,11 +1,16 @@
 package com.willfp.eco.core;
 
-import lombok.AccessLevel;
-import lombok.Getter;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Quick DI class to manage passing eco plugins.
+ * <p>
+ * Basically just a quick bit of laziness if you can't be bothered to add a private field
+ * and a protected getter, don't use this in kotlin as you can just specify
+ * {@code
+ * private val plugin: EcoPlugin
+ * }
+ * in the constructor.
  *
  * @param <T> The eco plugin type.
  */
@@ -13,7 +18,7 @@ public abstract class PluginDependent<T extends EcoPlugin> {
     /**
      * The {@link EcoPlugin} that is stored.
      */
-    @Getter(AccessLevel.PROTECTED)
+    @NotNull
     private final T plugin;
 
     /**
@@ -24,4 +29,14 @@ public abstract class PluginDependent<T extends EcoPlugin> {
     protected PluginDependent(@NotNull final T plugin) {
         this.plugin = plugin;
     }
+
+    /**
+     * Get the plugin.
+     *
+     * @return The plugin.
+     */
+    @NotNull
+    protected T getPlugin() {
+        return this.plugin;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/PluginLike.java

@@ -0,0 +1,37 @@
+package com.willfp.eco.core;
+
+import com.willfp.eco.core.config.updating.ConfigHandler;
+
+import java.io.File;
+import java.util.logging.Logger;
+
+/**
+ * Represents any class that acts like a plugin, for example {@link EcoPlugin}
+ * or {@link com.willfp.eco.core.extensions.Extension}. This exists to create
+ * things such as extension base configs rather than needing to pass an instance
+ * of the owning plugin.
+ */
+public interface PluginLike {
+    /**
+     * Get the data folder of the object.
+     * <p>
+     * Returns the plugin data folder for a plugin, or the extension's parent plugin's folder
+     *
+     * @return The data folder.
+     */
+    File getDataFolder();
+
+    /**
+     * Get the handler class for updatable classes.
+     *
+     * @return The config handler.
+     */
+    ConfigHandler getConfigHandler();
+
+    /**
+     * Get the logger.
+     *
+     * @return The logger.
+     */
+    Logger getLogger();
+}

eco-api/src/main/java/com/willfp/eco/core/PluginProps.java

@@ -0,0 +1,275 @@
+package com.willfp.eco.core;
+
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Plugin props are the arguments related to the plugin that are required on start-up.
+ * <p>
+ * This class is complex in how it works intentionally. This is done so that fields can be
+ * added to the props without breaking API backwards compatibility. Thus, there is no public
+ * constructor and no way to instantiate props without creating a parser.
+ */
+public final class PluginProps {
+    /**
+     * All registered parsers.
+     */
+    private static final Map<Class<?>, PropsParser<?>> REGISTERED_PARSERS = new HashMap<>();
+
+    /**
+     * The polymart resource ID.
+     */
+    @Nullable
+    private Integer resourceId;
+
+    /**
+     * The bStats ID.
+     */
+    @Nullable
+    private Integer bStatsId;
+
+    /**
+     * The proxy package.
+     */
+    @Nullable
+    private String proxyPackage;
+
+    /**
+     * The color.
+     */
+    @Nullable
+    private String color;
+
+    /**
+     * If extensions are supported.
+     */
+    @Nullable
+    private Boolean supportingExtensions;
+
+    /**
+     * Create new blank props.
+     */
+    private PluginProps() {
+
+    }
+
+    /**
+     * Get resource ID.
+     *
+     * @return The resource ID.
+     */
+    public int getResourceId() {
+        assert resourceId != null;
+        return resourceId;
+    }
+
+    /**
+     * Set resource ID.
+     *
+     * @param resourceId The resource ID.
+     */
+    public void setResourceId(final int resourceId) {
+        this.resourceId = resourceId;
+    }
+
+    /**
+     * Get bStats ID.
+     *
+     * @return The bStats ID.
+     */
+    public int getBStatsId() {
+        assert bStatsId != null;
+        return bStatsId;
+    }
+
+    /**
+     * Set bStats ID.
+     *
+     * @param bStatsId The bStats ID.
+     */
+    public void setBStatsId(final int bStatsId) {
+        this.bStatsId = bStatsId;
+    }
+
+    /**
+     * Get the proxy package.
+     *
+     * @return The package.
+     */
+    @NotNull
+    public String getProxyPackage() {
+        assert proxyPackage != null;
+        return proxyPackage;
+    }
+
+    /**
+     * Set the proxy package.
+     *
+     * @param proxyPackage The proxy package.
+     */
+    public void setProxyPackage(@NotNull final String proxyPackage) {
+        this.proxyPackage = proxyPackage;
+    }
+
+    /**
+     * Get color.
+     *
+     * @return The color.
+     */
+    @NotNull
+    public String getColor() {
+        assert color != null;
+        return color;
+    }
+
+    /**
+     * Set the color.
+     *
+     * @param color The color.
+     */
+    public void setColor(@NotNull final String color) {
+        this.color = color;
+    }
+
+    /**
+     * Get if extensions are supported.
+     *
+     * @return If supported.
+     */
+    public boolean isSupportingExtensions() {
+        assert supportingExtensions != null;
+        return supportingExtensions;
+    }
+
+    /**
+     * Set if extensions are supported.
+     *
+     * @param supportingExtensions If supported.
+     */
+    public void setSupportingExtensions(final boolean supportingExtensions) {
+        this.supportingExtensions = supportingExtensions;
+    }
+
+    /**
+     * Ensure that all required props have been set.
+     */
+    public void validate() {
+        if (
+                supportingExtensions == null
+                        || proxyPackage == null
+                        || color == null
+                        || bStatsId == null
+                        || resourceId == null
+        ) {
+            throw new IllegalStateException("Missing required props!");
+        }
+    }
+
+    /**
+     * Parse props from source.
+     *
+     * @param source      The source.
+     * @param sourceClass The source class.
+     * @param <T>         The source type.
+     * @return The props.
+     */
+    public static <T> PluginProps parse(@NotNull final T source,
+                                        @NotNull final Class<? extends T> sourceClass) {
+        for (Map.Entry<Class<?>, PropsParser<?>> entry : REGISTERED_PARSERS.entrySet()) {
+            Class<?> clazz = entry.getKey();
+
+            if (clazz.equals(sourceClass)) {
+                @SuppressWarnings("unchecked")
+                PropsParser<T> parser = (PropsParser<T>) entry.getValue();
+                return parser.parseFrom(source);
+            }
+        }
+
+        throw new IllegalArgumentException("No parser exists for class " + sourceClass);
+    }
+
+    /**
+     * Register a parser for a type.
+     *
+     * @param clazz  The class.
+     * @param parser The parser.
+     * @param <T>    The source type.
+     */
+    public static <T> void registerParser(@NotNull final Class<T> clazz,
+                                          @NotNull final PropsParser<T> parser) {
+        REGISTERED_PARSERS.put(clazz, parser);
+    }
+
+    /**
+     * Get if there is a registered parser for a class.
+     *
+     * @param clazz The class.
+     * @return If there is a parser registered.
+     */
+    public static boolean hasParserFor(@NotNull final Class<?> clazz) {
+        for (Class<?> test : REGISTERED_PARSERS.keySet()) {
+            if (test.equals(clazz)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Create new props from known values.
+     *
+     * Marked as internal as this method will break whenever the properties themselves
+     * are updated (e.g. if a new property is added) - so to prevent any potential
+     * backwards-compatibility bugs, this method cannot be invoked outside eco itself.
+     *
+     * @param resourceId         The ID of the plugin on polymart.
+     * @param bStatsId           The ID of the plugin on bStats.
+     * @param proxyPackage       The package where proxies can be found.
+     * @param color              The primary color of the plugin.
+     * @param supportsExtensions If the plugin should attempt to look for extensions.
+     * @return The props.
+     */
+    @ApiStatus.Internal
+    static PluginProps createSimple(final int resourceId,
+                                    final int bStatsId,
+                                    @NotNull final String proxyPackage,
+                                    @NotNull final String color,
+                                    final boolean supportsExtensions) {
+        PluginProps props = new PluginProps();
+        props.setResourceId(resourceId);
+        props.setBStatsId(bStatsId);
+        props.setProxyPackage(proxyPackage);
+        props.setColor(color);
+        props.setSupportingExtensions(supportsExtensions);
+        return props;
+    }
+
+    /**
+     * Parse arguments into props for a plugin.
+     *
+     * @param <T> The type of source.
+     */
+    public interface PropsParser<T> {
+        /**
+         * Parse props from a given source.
+         *
+         * @param source The source.
+         * @return The props.
+         */
+        PluginProps parseFrom(@NotNull T source);
+
+        /**
+         * Get a new, blank props instance.
+         *
+         * @return Blank props.
+         */
+        default PluginProps getBlankProps() {
+            return new PluginProps();
+        }
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/Prerequisite.java

@@ -1,8 +1,8 @@
 package com.willfp.eco.core;
 
+import com.willfp.eco.core.integrations.economy.EconomyManager;
 import com.willfp.eco.core.proxy.ProxyConstants;
 import com.willfp.eco.util.ClassUtils;
-import lombok.Getter;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
@@ -30,18 +30,52 @@ public class Prerequisite {
             "Requires server to be running paper (or a fork)"
     );
 
+    /**
+     * Requires the server to have vault installed.
+     *
+     * @deprecated Use {@link EconomyManager#hasRegistrations()} instead.
+     */
+    @Deprecated
+    public static final Prerequisite HAS_VAULT = new Prerequisite(
+            () -> ClassUtils.exists("net.milkbowl.vault.economy.Economy"),
+            "Requires server to have vault"
+    );
+
+    /**
+     * Requires the server to be running 1.18.
+     */
+    public static final Prerequisite HAS_1_18 = new Prerequisite(
+            () -> ProxyConstants.NMS_VERSION.contains("18"),
+            "Requires server to be running 1.18+"
+    );
+
     /**
      * Requires the server to be running 1.17.
      */
     public static final Prerequisite HAS_1_17 = new Prerequisite(
-            () -> ProxyConstants.NMS_VERSION.contains("17"),
+            () -> ProxyConstants.NMS_VERSION.contains("17") || HAS_1_18.isMet(),
             "Requires server to be running 1.17+"
     );
 
+    /**
+     * Requires the server to be running an implementation of BungeeCord.
+     */
+    public static final Prerequisite HAS_BUNGEECORD = new Prerequisite(
+            () -> ClassUtils.exists("net.md_5.bungee.api.event.ServerConnectedEvent"),
+            "Requires server to be running BungeeCord (or a fork)"
+    );
+
+    /**
+     * Requires the server to be running an implementation of Velocity.
+     */
+    public static final Prerequisite HAS_VELOCITY = new Prerequisite(
+            () -> ClassUtils.exists("com.velocitypowered.api.event.player.ServerConnectedEvent"),
+            "Requires server to be running Velocity (or a fork)"
+    );
+
     /**
      * If the necessary prerequisite condition has been met.
      */
-    @Getter
     private boolean isMet;
 
     /**
@@ -52,7 +86,6 @@ public class Prerequisite {
     /**
      * The description of the requirements of the prerequisite.
      */
-    @Getter
     private final String description;
 
     /**
@@ -97,4 +130,22 @@ public class Prerequisite {
     static {
         update();
     }
+
+    /**
+     * Get if the prerequisite is met.
+     *
+     * @return If the condition is met.
+     */
+    public boolean isMet() {
+        return this.isMet;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return The description.
+     */
+    public String getDescription() {
+        return this.description;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/command/CommandBase.java

@@ -1,7 +1,12 @@
 package com.willfp.eco.core.command;
 
+import com.willfp.eco.core.EcoPlugin;
+import org.bukkit.command.CommandSender;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * Interface for all command implementations.
  */
@@ -35,17 +40,77 @@ public interface CommandBase {
      */
     CommandBase addSubcommand(@NotNull CommandBase command);
 
+    /**
+     * Handle command execution.
+     * <p>
+     * Marked as default void with no implementation for backwards compatibility.
+     *
+     * @param sender The sender.
+     * @param args   The args.
+     */
+    default void onExecute(@NotNull CommandSender sender,
+                           @NotNull List<String> args) {
+        // Do nothing.
+    }
+
+    /**
+     * Handle tab completion.
+     * <p>
+     * Marked as default void with no implementation for backwards compatibility.
+     *
+     * @param sender The sender.
+     * @param args   The args.
+     * @return The results.
+     */
+    default List<String> tabComplete(@NotNull CommandSender sender,
+                                     @NotNull List<String> args) {
+        return new ArrayList<>();
+    }
+
+    /**
+     * Get the plugin.
+     *
+     * @return The plugin.
+     */
+    EcoPlugin getPlugin();
+
     /**
      * Get the handler.
      *
      * @return The handler.
+     * @see CommandHandler
+     * @deprecated Use {@link CommandBase#onExecute(CommandSender, List)} instead.
      */
+    @Deprecated
     CommandHandler getHandler();
 
+    /**
+     * Set the handler.
+     *
+     * @param handler The handler.
+     * @see CommandHandler
+     * @deprecated Handlers have been deprecated.
+     */
+    @Deprecated
+    void setHandler(@NotNull CommandHandler handler);
+
     /**
      * Get the tab completer.
      *
      * @return The tab completer.
+     * @see TabCompleteHandler
+     * @deprecated Use {@link CommandBase#tabComplete(CommandSender, List)} instead.
      */
+    @Deprecated
     TabCompleteHandler getTabCompleter();
+
+    /**
+     * Set the tab completer.
+     *
+     * @param handler The handler.
+     * @see TabCompleteHandler
+     * @deprecated Handlers have been deprecated.
+     */
+    @Deprecated
+    void setTabCompleter(@NotNull TabCompleteHandler handler);
 }

eco-api/src/main/java/com/willfp/eco/core/command/CommandHandler.java

@@ -10,9 +10,13 @@ import java.util.List;
  * A command handler handles the actual code for a command.
  * <p>
  * The replacement for {@link org.bukkit.command.CommandExecutor#onCommand(CommandSender, Command, String, String[])}
+ *
  * @see CommandBase
+ * @deprecated Handlers have been deprecated. This legacy system will eventually be removed,
+ * update to use the new system: {@link CommandBase#onExecute(CommandSender, List)}.
  */
 @FunctionalInterface
+@Deprecated(since = "6.17.0")
 public interface CommandHandler {
     /**
      * The code to be called on execution.

eco-api/src/main/java/com/willfp/eco/core/command/TabCompleteHandler.java

@@ -10,9 +10,13 @@ import java.util.List;
  * A Tab Complete handler handles the actual tab-completion code.
  * <p>
  * The replacement for {@link org.bukkit.command.TabCompleter#onTabComplete(CommandSender, Command, String, String[])}
+ *
  * @see CommandBase
+ * @deprecated Handlers have been deprecated. This legacy system will eventually be removed,
+ * update to use the new system: {@link CommandBase#tabComplete(CommandSender, List)}
  */
 @FunctionalInterface
+@Deprecated(since = "6.17.0")
 public interface TabCompleteHandler {
     /**
      * Handle Tab Completion.

eco-api/src/main/java/com/willfp/eco/core/command/impl/HandledCommand.java

@@ -1,16 +1,14 @@
 package com.willfp.eco.core.command.impl;
 
 import com.willfp.eco.core.EcoPlugin;
-import com.willfp.eco.core.PluginDependent;
 import com.willfp.eco.core.command.CommandBase;
 import com.willfp.eco.core.command.CommandHandler;
 import com.willfp.eco.core.command.TabCompleteHandler;
-import lombok.AccessLevel;
-import lombok.Getter;
 import org.bukkit.command.CommandSender;
 import org.bukkit.entity.Player;
 import org.bukkit.util.StringUtil;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -25,11 +23,16 @@ import java.util.stream.Collectors;
  * in order to execute the command-specific code. It's essentially an internal
  * layer, hence why it's a package-private class.
  */
-abstract class HandledCommand extends PluginDependent<EcoPlugin> implements CommandBase {
+@SuppressWarnings({"DeprecatedIsStillUsed"})
+abstract class HandledCommand implements CommandBase {
+    /**
+     * The plugin.
+     */
+    private final EcoPlugin plugin;
+
     /**
      * The name of the command.
      */
-    @Getter
     private final String name;
 
     /**
@@ -37,7 +40,6 @@ abstract class HandledCommand extends PluginDependent<EcoPlugin> implements Comm
      * <p>
      * Written out as a string for flexibility with subclasses.
      */
-    @Getter
     private final String permission;
 
     /**
@@ -45,13 +47,25 @@ abstract class HandledCommand extends PluginDependent<EcoPlugin> implements Comm
      * <p>
      * In other worlds, only allowed to be executed by console.
      */
-    @Getter
     private final boolean playersOnly;
 
+    /**
+     * The actual code to be executed in the command.
+     */
+    @Deprecated
+    @Nullable
+    private CommandHandler handler = null;
+
+    /**
+     * The tab completion code to be executed in the command.
+     */
+    @Deprecated
+    @Nullable
+    private TabCompleteHandler tabCompleter = null;
+
     /**
      * All subcommands for the command.
      */
-    @Getter(AccessLevel.PROTECTED)
     private final List<CommandBase> subcommands;
 
     /**
@@ -68,7 +82,7 @@ abstract class HandledCommand extends PluginDependent<EcoPlugin> implements Comm
                    @NotNull final String name,
                    @NotNull final String permission,
                    final boolean playersOnly) {
-        super(plugin);
+        this.plugin = plugin;
         this.name = name;
         this.permission = permission;
         this.playersOnly = playersOnly;
@@ -88,6 +102,16 @@ abstract class HandledCommand extends PluginDependent<EcoPlugin> implements Comm
         return this;
     }
 
+    /**
+     * Get the plugin.
+     *
+     * @return The plugin.
+     */
+    @Override
+    public EcoPlugin getPlugin() {
+        return this.plugin;
+    }
+
     /**
      * Handle the command.
      *
@@ -114,7 +138,16 @@ abstract class HandledCommand extends PluginDependent<EcoPlugin> implements Comm
             }
         }
 
-        this.getHandler().onExecute(sender, Arrays.asList(args));
+        if (this.isPlayersOnly() && !(sender instanceof Player)) {
+            sender.sendMessage(this.getPlugin().getLangYml().getMessage("not-player"));
+            return;
+        }
+
+        if (this.getHandler() != null) {
+            this.getHandler().onExecute(sender, Arrays.asList(args));
+        } else {
+            this.onExecute(sender, Arrays.asList(args));
+        }
     }
 
     /**
@@ -161,15 +194,11 @@ abstract class HandledCommand extends PluginDependent<EcoPlugin> implements Comm
             }
         }
 
-        return this.getTabCompleter().tabComplete(sender, Arrays.asList(args));
+        if (this.getTabCompleter() != null) {
-    }
+            return this.getTabCompleter().tabComplete(sender, Arrays.asList(args));
-
+        } else {
-    @Override
+            return this.tabComplete(sender, Arrays.asList(args));
-    public abstract CommandHandler getHandler();
+        }
-
-    @Override
-    public TabCompleteHandler getTabCompleter() {
-        return (sender, args) -> new ArrayList<>();
     }
 
     /**
@@ -183,11 +212,6 @@ abstract class HandledCommand extends PluginDependent<EcoPlugin> implements Comm
     public static boolean canExecute(@NotNull final CommandSender sender,
                                      @NotNull final CommandBase command,
                                      @NotNull final EcoPlugin plugin) {
-        if (command.isPlayersOnly() && !(sender instanceof Player)) {
-            sender.sendMessage(plugin.getLangYml().getMessage("not-player"));
-            return false;
-        }
-
         if (!sender.hasPermission(command.getPermission()) && sender instanceof Player) {
             sender.sendMessage(plugin.getLangYml().getNoPermission());
             return false;
@@ -195,4 +219,64 @@ abstract class HandledCommand extends PluginDependent<EcoPlugin> implements Comm
 
         return true;
     }
+
+    /**
+     * Get the command name.
+     *
+     * @return The name.
+     */
+    public String getName() {
+        return this.name;
+    }
+
+    /**
+     * Get the permission required to execute the command.
+     *
+     * @return The permission.
+     */
+    public String getPermission() {
+        return this.permission;
+    }
+
+    /**
+     * Get if the command can only be executed by players.
+     *
+     * @return If players only.
+     */
+    public boolean isPlayersOnly() {
+        return this.playersOnly;
+    }
+
+    /**
+     * Get the subcommands of the command.
+     *
+     * @return The subcommands.
+     */
+    public List<CommandBase> getSubcommands() {
+        return this.subcommands;
+    }
+
+    @Deprecated
+    @Override
+    public @Nullable CommandHandler getHandler() {
+        return this.handler;
+    }
+
+    @Deprecated
+    @Override
+    public @Nullable TabCompleteHandler getTabCompleter() {
+        return this.tabCompleter;
+    }
+
+    @Deprecated
+    @Override
+    public void setHandler(@Nullable final CommandHandler handler) {
+        this.handler = handler;
+    }
+
+    @Deprecated
+    @Override
+    public void setTabCompleter(@Nullable final TabCompleteHandler tabCompleter) {
+        this.tabCompleter = tabCompleter;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/command/impl/PluginCommand.java

@@ -12,7 +12,9 @@ import org.jetbrains.annotations.Nullable;
 import java.util.List;
 
 /**
- * PluginCommands are the class to be used instead of CommandExecutor.
+ * PluginCommands are the class to be used instead of CommandExecutor,
+ * they function as the base command, e.g. {@code /ecoenchants} would be a base command, with each
+ * subsequent argument functioning as subcommands.
  * <p>
  * The command will not be registered until register() is called.
  * <p>

eco-api/src/main/java/com/willfp/eco/core/config/BaseConfig.java

@@ -0,0 +1,35 @@
+package com.willfp.eco.core.config;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.wrapper.LoadableConfigWrapper;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Config implementation for configs present in the plugin's base directory (eg config.yml, lang.yml).
+ * <p>
+ * Automatically updates.
+ */
+public abstract class BaseConfig extends LoadableConfigWrapper {
+    /**
+     * Create new Base Config.
+     *
+     * @param plugin       The plugin or extension.
+     * @param configName   The config name (excluding extension).
+     * @param removeUnused If unused sections should be removed.
+     * @param type         The config type.
+     */
+    protected BaseConfig(@NotNull final String configName,
+                         @NotNull final PluginLike plugin,
+                         final boolean removeUnused,
+                         @NotNull final ConfigType type) {
+        super(Eco.getHandler().getConfigFactory().createUpdatableConfig(
+                configName,
+                plugin,
+                "",
+                plugin.getClass(),
+                removeUnused,
+                type
+        ));
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/config/ConfigType.java

@@ -0,0 +1,16 @@
+package com.willfp.eco.core.config;
+
+/**
+ * Config types, classified by file extension.
+ */
+public enum ConfigType {
+    /**
+     * .json config.
+     */
+    JSON,
+
+    /**
+     * .yml config.
+     */
+    YAML
+}

eco-api/src/main/java/com/willfp/eco/core/config/ExtendableConfig.java

@@ -0,0 +1,44 @@
+package com.willfp.eco.core.config;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.wrapper.LoadableConfigWrapper;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Config implementation for configs present in one of two places:
+ * <ul>
+ *     <li>Plugin base directory (eg config.yml, lang.json)</li>
+ *     <li>Other extension's configs</li>
+ * </ul>
+ * <p>
+ * Automatically updates.
+ */
+public abstract class ExtendableConfig extends LoadableConfigWrapper {
+    /**
+     * @param configName       The name of the config
+     * @param removeUnused     Whether keys not present in the default config should be removed on update.
+     * @param plugin           The plugin.
+     * @param updateBlacklist  Substring of keys to not add/remove keys for.
+     * @param subDirectoryPath The subdirectory path.
+     * @param type             The config type.
+     * @param source           The class that owns the resource.
+     */
+    protected ExtendableConfig(@NotNull final String configName,
+                               final boolean removeUnused,
+                               @NotNull final PluginLike plugin,
+                               @NotNull final Class<?> source,
+                               @NotNull final String subDirectoryPath,
+                               @NotNull final ConfigType type,
+                               @NotNull final String... updateBlacklist) {
+        super(Eco.getHandler().getConfigFactory().createUpdatableConfig(
+                configName,
+                plugin,
+                subDirectoryPath,
+                source,
+                removeUnused,
+                type,
+                updateBlacklist
+        ));
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/config/StaticBaseConfig.java

@@ -0,0 +1,32 @@
+package com.willfp.eco.core.config;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.wrapper.LoadableConfigWrapper;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Non-updatable yaml config that exists within a plugin jar.
+ */
+public abstract class StaticBaseConfig extends LoadableConfigWrapper {
+    /**
+     * Config implementation for configs present in the plugin's base directory (eg config.yml, lang.yml).
+     * <p>
+     * Does not automatically update.
+     *
+     * @param configName The name of the config
+     * @param plugin     The plugin.
+     * @param type       The config type.
+     */
+    protected StaticBaseConfig(@NotNull final String configName,
+                               @NotNull final PluginLike plugin,
+                               @NotNull final ConfigType type) {
+        super(Eco.getHandler().getConfigFactory().createLoadableConfig(
+                configName,
+                plugin,
+                "",
+                plugin.getClass(),
+                type
+        ));
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/config/TransientConfig.java

@@ -0,0 +1,60 @@
+package com.willfp.eco.core.config;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.config.interfaces.Config;
+import com.willfp.eco.core.config.wrapper.ConfigWrapper;
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.Map;
+
+/**
+ * Config that exists purely in the code, not linked to any file.
+ * <p>
+ * Use for inline configs to move data around or to add subsections to other configs.
+ */
+public class TransientConfig extends ConfigWrapper<Config> {
+    /**
+     * @param config The YamlConfiguration handle.
+     */
+    public TransientConfig(@NotNull final YamlConfiguration config) {
+        super(Eco.getHandler().getConfigFactory().createConfig(config));
+    }
+
+    /**
+     * @param stream The InputStream.
+     */
+    public TransientConfig(@Nullable final InputStream stream) {
+        super(stream != null ? Eco.getHandler().getConfigFactory().createConfig(YamlConfiguration.loadConfiguration(
+                new InputStreamReader(stream)
+        )) : new TransientConfig());
+    }
+
+    /**
+     * Create a new empty transient config.
+     *
+     * @param values The values.
+     */
+    public TransientConfig(@NotNull final Map<String, Object> values) {
+        super(Eco.getHandler().getConfigFactory().createConfig(values));
+    }
+
+    /**
+     * Create a new empty transient config.
+     */
+    public TransientConfig() {
+        super(Eco.getHandler().getConfigFactory().createConfig("", ConfigType.YAML));
+    }
+
+    /**
+     * @param contents The contents of the config.
+     * @param type     The config type.
+     */
+    public TransientConfig(@NotNull final String contents,
+                           @NotNull final ConfigType type) {
+        super(Eco.getHandler().getConfigFactory().createConfig(contents, type));
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/config/base/ConfigYml.java

@@ -1,19 +1,55 @@
 package com.willfp.eco.core.config.base;
 
 import com.willfp.eco.core.EcoPlugin;
-import com.willfp.eco.core.config.yaml.YamlBaseConfig;
+import com.willfp.eco.core.config.BaseConfig;
+import com.willfp.eco.core.config.ConfigType;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Default plugin config.yml.
  */
-public class ConfigYml extends YamlBaseConfig {
+public class ConfigYml extends BaseConfig {
     /**
      * Config.yml.
      *
      * @param plugin The plugin.
      */
     public ConfigYml(@NotNull final EcoPlugin plugin) {
-        super("config", true, plugin);
+        super("config", plugin, true, ConfigType.YAML);
+    }
+
+    /**
+     * Config.yml.
+     *
+     * @param plugin       The plugin.
+     * @param removeUnused Remove unused.
+     */
+    public ConfigYml(@NotNull final EcoPlugin plugin,
+                     final boolean removeUnused) {
+        super("config", plugin, removeUnused, ConfigType.YAML);
+    }
+
+    /**
+     * Config.yml.
+     *
+     * @param plugin The plugin.
+     * @param name   The config name.
+     */
+    public ConfigYml(@NotNull final EcoPlugin plugin,
+                     @NotNull final String name) {
+        super(name, plugin, true, ConfigType.YAML);
+    }
+
+    /**
+     * Config.yml.
+     *
+     * @param plugin       The plugin.
+     * @param name         The config name.
+     * @param removeUnused Remove unused.
+     */
+    public ConfigYml(@NotNull final EcoPlugin plugin,
+                     @NotNull final String name,
+                     final boolean removeUnused) {
+        super(name, plugin, removeUnused, ConfigType.YAML);
     }
 }

eco-api/src/main/java/com/willfp/eco/core/config/base/LangYml.java

@@ -1,20 +1,22 @@
 package com.willfp.eco.core.config.base;
 
 import com.willfp.eco.core.EcoPlugin;
-import com.willfp.eco.core.config.yaml.YamlBaseConfig;
+import com.willfp.eco.core.config.BaseConfig;
+import com.willfp.eco.core.config.ConfigType;
+import com.willfp.eco.util.StringUtils;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Default plugin lang.yml.
  */
-public class LangYml extends YamlBaseConfig {
+public class LangYml extends BaseConfig {
     /**
      * Lang.yml.
      *
      * @param plugin The plugin.
      */
     public LangYml(@NotNull final EcoPlugin plugin) {
-        super("lang", false, plugin);
+        super("lang", plugin, false, ConfigType.YAML);
     }
 
     /**
@@ -23,7 +25,7 @@ public class LangYml extends YamlBaseConfig {
      * @return The prefix.
      */
     public String getPrefix() {
-        return this.getString("messages.prefix");
+        return this.getFormattedString("messages.prefix");
     }
 
     /**
@@ -32,7 +34,7 @@ public class LangYml extends YamlBaseConfig {
      * @return The message.
      */
     public String getNoPermission() {
-        return getPrefix() + this.getString("messages.no-permission");
+        return getPrefix() + this.getFormattedString("messages.no-permission");
     }
 
     /**
@@ -42,6 +44,18 @@ public class LangYml extends YamlBaseConfig {
      * @return The message with a prefix appended.
      */
     public String getMessage(@NotNull final String message) {
-        return getPrefix() + this.getString("messages." + message);
+        return getMessage(message, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
+
+    /**
+     * Get a chat message.
+     *
+     * @param message The key of the message.
+     * @param option  The format options.
+     * @return The message with a prefix appended.
+     */
+    public String getMessage(@NotNull final String message,
+                             @NotNull final StringUtils.FormatOption option) {
+        return getPrefix() + this.getFormattedString("messages." + message, option);
     }
 }

eco-api/src/main/java/com/willfp/eco/core/config/interfaces/Config.java

@@ -1,15 +1,23 @@
 package com.willfp.eco.core.config.interfaces;
 
+import com.willfp.eco.core.config.ConfigType;
+import com.willfp.eco.core.config.TransientConfig;
+import com.willfp.eco.util.NumberUtils;
+import com.willfp.eco.util.StringUtils;
+import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 /**
- * All canfigs implement this interface.
+ * All configs implement this interface.
  * <p>
  * Contains all methods that must exist in yaml and json configurations.
  */
+@SuppressWarnings("unused")
 public interface Config extends Cloneable {
     /**
      * Clears cache.
@@ -64,10 +72,12 @@ public interface Config extends Cloneable {
      * Get subsection from config.
      *
      * @param path The key to check.
-     * @return The subsection. Throws NPE if not found.
+     * @return The subsection. Returns an empty section if not found.
      */
     @NotNull
-    Config getSubsection(@NotNull String path);
+    default Config getSubsection(@NotNull String path) {
+        return Objects.requireNonNullElse(getSubsectionOrNull(path), new TransientConfig());
+    }
 
     /**
      * Get subsection from config.
@@ -84,7 +94,44 @@ public interface Config extends Cloneable {
      * @param path The key to fetch the value from.
      * @return The found value, or 0 if not found.
      */
-    int getInt(@NotNull String path);
+    default int getInt(@NotNull String path) {
+        return Objects.requireNonNullElse(getIntOrNull(path), 0);
+    }
+
+    /**
+     * Get an integer from config with a specified default (not found) value.
+     *
+     * @param path The key to fetch the value from.
+     * @param def  The value to default to if not found.
+     * @return The found value, or the default.
+     */
+    default int getInt(@NotNull String path,
+                       int def) {
+        return Objects.requireNonNullElse(getIntOrNull(path), def);
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path The key to fetch the value from.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default int getIntFromExpression(@NotNull String path) {
+        return getIntFromExpression(path, null);
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path   The key to fetch the value from.
+     * @param player The player to evaluate placeholders with respect to.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default int getIntFromExpression(@NotNull String path,
+                                     @Nullable Player player) {
+        return Double.valueOf(getDoubleFromExpression(path, player)).intValue();
+    }
+
 
     /**
      * Get an integer from config.
@@ -95,16 +142,6 @@ public interface Config extends Cloneable {
     @Nullable
     Integer getIntOrNull(@NotNull String path);
 
-    /**
-     * Get an integer from config with a specified default (not found) value.
-     *
-     * @param path The key to fetch the value from.
-     * @param def  The value to default to if not found.
-     * @return The found value, or the default.
-     */
-    int getInt(@NotNull String path,
-               int def);
-
     /**
      * Get a list of integers from config.
      *
@@ -112,7 +149,9 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<Integer> getInts(@NotNull String path);
+    default List<Integer> getInts(@NotNull String path) {
+        return Objects.requireNonNullElse(getIntsOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of integers from config.
@@ -129,7 +168,9 @@ public interface Config extends Cloneable {
      * @param path The key to fetch the value from.
      * @return The found value, or false if not found.
      */
-    boolean getBool(@NotNull String path);
+    default boolean getBool(@NotNull String path) {
+        return Objects.requireNonNullElse(getBoolOrNull(path), false);
+    }
 
     /**
      * Get a boolean from config.
@@ -147,7 +188,9 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<Boolean> getBools(@NotNull String path);
+    default List<Boolean> getBools(@NotNull String path) {
+        return Objects.requireNonNullElse(getBoolsOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of booleans from config.
@@ -159,13 +202,41 @@ public interface Config extends Cloneable {
     List<Boolean> getBoolsOrNull(@NotNull String path);
 
     /**
-     * Get a string from config.
+     * Get a formatted string from config.
      *
      * @param path The key to fetch the value from.
      * @return The found value, or an empty string if not found.
      */
     @NotNull
-    String getString(@NotNull String path);
+    default String getFormattedString(@NotNull String path) {
+        return getString(path, true, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
+
+    /**
+     * Get a formatted string from config.
+     *
+     * @param path   The key to fetch the value from.
+     * @param option The format option.
+     * @return The found value, or an empty string if not found.
+     */
+    @NotNull
+    default String getFormattedString(@NotNull String path,
+                                      @NotNull StringUtils.FormatOption option) {
+        return getString(path, true, option);
+    }
+
+    /**
+     * Get a string from config.
+     * <p>
+     * Not formatted.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or an empty string if not found.
+     */
+    @NotNull
+    default String getString(@NotNull String path) {
+        return getString(path, false, StringUtils.FormatOption.WITHOUT_PLACEHOLDERS);
+    }
 
     /**
      * Get a string from config.
@@ -173,19 +244,80 @@ public interface Config extends Cloneable {
      * @param path   The key to fetch the value from.
      * @param format If the string should be formatted.
      * @return The found value, or an empty string if not found.
+     * @deprecated Since 6.18.0, {@link Config#getString(String)} is not formatted by default.
      */
-    @NotNull
+    @Deprecated(since = "6.18.0")
-    String getString(@NotNull String path,
+    default String getString(@NotNull String path,
-                     boolean format);
+                             boolean format) {
+        return this.getString(path, format, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
 
     /**
      * Get a string from config.
      *
+     * @param path   The key to fetch the value from.
+     * @param option The format option.
+     * @return The found value, or an empty string if not found.
+     * @deprecated Use {@link Config#getFormattedString(String, StringUtils.FormatOption)} instead.
+     */
+    @NotNull
+    @Deprecated
+    default String getString(@NotNull String path,
+                             @NotNull final StringUtils.FormatOption option) {
+        return this.getString(path, true, option);
+    }
+
+    /**
+     * Get a string from config.
+     *
+     * @param path   The key to fetch the value from.
+     * @param format If the string should be formatted.
+     * @param option The format option.
+     * @return The found value, or an empty string if not found.
+     */
+    @NotNull
+    default String getString(@NotNull String path,
+                             boolean format,
+                             @NotNull StringUtils.FormatOption option) {
+        return Objects.requireNonNullElse(getStringOrNull(path, format, option), "");
+    }
+
+    /**
+     * Get a formatted string from config.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or an empty string if not found.
+     */
+    @Nullable
+    default String getFormattedStringOrNull(@NotNull String path) {
+        return getStringOrNull(path, true, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
+
+    /**
+     * Get a formatted string from config.
+     *
+     * @param path   The key to fetch the value from.
+     * @param option The format option.
+     * @return The found value, or an empty string if not found.
+     */
+    @Nullable
+    default String getFormattedStringOrNull(@NotNull String path,
+                                            @NotNull StringUtils.FormatOption option) {
+        return getStringOrNull(path, true, option);
+    }
+
+    /**
+     * Get a string from config.
+     * <p>
+     * Formatted by default.
+     *
      * @param path The key to fetch the value from.
      * @return The found value, or null if not found.
      */
     @Nullable
-    String getStringOrNull(@NotNull String path);
+    default String getStringOrNull(@NotNull String path) {
+        return getStringOrNull(path, false, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
 
     /**
      * Get a string from config.
@@ -193,10 +325,42 @@ public interface Config extends Cloneable {
      * @param path   The key to fetch the value from.
      * @param format If the string should be formatted.
      * @return The found value, or null if not found.
+     * @deprecated Since 6.18.0, {@link Config#getString(String)} is not formatted by default.
+     */
+    @Nullable
+    @Deprecated(since = "6.18.0")
+    default String getStringOrNull(@NotNull String path,
+                                   boolean format) {
+        return this.getStringOrNull(path, format, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
+
+    /**
+     * Get a string from config.
+     *
+     * @param path   The key to fetch the value from.
+     * @param option The format option.
+     * @return The found value, or null if not found.
+     * @deprecated Use {@link Config#getFormattedString(String, StringUtils.FormatOption)} instead.
+     */
+    @Nullable
+    @Deprecated
+    default String getStringOrNull(@NotNull String path,
+                                   @NotNull StringUtils.FormatOption option) {
+        return this.getStringOrNull(path, true, option);
+    }
+
+    /**
+     * Get a string from config.
+     *
+     * @param path   The key to fetch the value from.
+     * @param format If the string should be formatted.
+     * @param option The format option. If format is false, this will be ignored.
+     * @return The found value, or null if not found.
      */
     @Nullable
     String getStringOrNull(@NotNull String path,
-                           boolean format);
+                           boolean format,
+                           @NotNull StringUtils.FormatOption option);
 
     /**
      * Get a list of strings from config.
@@ -207,7 +371,37 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<String> getStrings(@NotNull String path);
+    default List<String> getFormattedStrings(@NotNull String path) {
+        return getStrings(path, true, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
+
+    /**
+     * Get a list of strings from config.
+     * <p>
+     * Formatted by default.
+     *
+     * @param path   The key to fetch the value from.
+     * @param option The format option.
+     * @return The found value, or a blank {@link java.util.ArrayList} if not found.
+     */
+    @NotNull
+    default List<String> getFormattedStrings(@NotNull String path,
+                                             @NotNull StringUtils.FormatOption option) {
+        return getStrings(path, true, option);
+    }
+
+    /**
+     * Get a list of strings from config.
+     * <p>
+     * Not formatted.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or a blank {@link java.util.ArrayList} if not found.
+     */
+    @NotNull
+    default List<String> getStrings(@NotNull String path) {
+        return getStrings(path, false, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
 
     /**
      * Get a list of strings from config.
@@ -215,19 +409,87 @@ public interface Config extends Cloneable {
      * @param path   The key to fetch the value from.
      * @param format If the strings should be formatted.
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
+     * @deprecated Since 6.18.0, {@link Config#getString(String)} is not formatted by default.
      */
     @NotNull
-    List<String> getStrings(@NotNull String path,
+    @Deprecated(since = "6.18.0")
-                            boolean format);
+    default List<String> getStrings(@NotNull String path,
+                                    boolean format) {
+        return this.getStrings(path, format, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
 
     /**
      * Get a list of strings from config.
      *
+     * @param path   The key to fetch the value from.
+     * @param option The format option.
+     * @return The found value, or a blank {@link java.util.ArrayList} if not found.
+     * @deprecated Use {@link Config#getFormattedStrings(String, StringUtils.FormatOption)} instead.
+     */
+    @NotNull
+    @Deprecated
+    default List<String> getStrings(@NotNull String path,
+                                    @NotNull StringUtils.FormatOption option) {
+        return getStrings(path, false, option);
+    }
+
+    /**
+     * Get a list of strings from config.
+     *
+     * @param path   The key to fetch the value from.
+     * @param format If the strings should be formatted.
+     * @param option The option.
+     * @return The found value, or a blank {@link java.util.ArrayList} if not found.
+     */
+    @NotNull
+    default List<String> getStrings(@NotNull String path,
+                                    boolean format,
+                                    @NotNull StringUtils.FormatOption option) {
+        return Objects.requireNonNullElse(getStringsOrNull(path, format, option), new ArrayList<>());
+    }
+
+    /**
+     * Get a list of strings from config.
+     * <p>
+     * Formatted.
+     *
      * @param path The key to fetch the value from.
      * @return The found value, or null if not found.
      */
     @Nullable
-    List<String> getStringsOrNull(@NotNull String path);
+    default List<String> getFormattedStringsOrNull(@NotNull String path) {
+        return getStringsOrNull(path, true, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
+
+    /**
+     * Get a list of strings from config.
+     * <p>
+     * Formatted.
+     *
+     * @param path   The key to fetch the value from.
+     * @param option The format option.
+     * @return The found value, or null if not found.
+     */
+    @Nullable
+    default List<String> getFormattedStringsOrNull(@NotNull String path,
+                                                   @NotNull StringUtils.FormatOption option) {
+        return getStringsOrNull(path, true, option);
+    }
+
+    /**
+     * Get a list of strings from config.
+     * <p>
+     * Not formatted.
+     * <p>
+     * This will be changed in newer versions to <b>not</b> format by default.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or null if not found.
+     */
+    @Nullable
+    default List<String> getStringsOrNull(@NotNull String path) {
+        return getStringsOrNull(path, false, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
 
     /**
      * Get a list of strings from config.
@@ -235,10 +497,42 @@ public interface Config extends Cloneable {
      * @param path   The key to fetch the value from.
      * @param format If the strings should be formatted.
      * @return The found value, or null if not found.
+     * @deprecated Since 6.18.0, {@link Config#getString(String)} is not formatted by default.
+     */
+    @Nullable
+    @Deprecated(since = "6.18.0")
+    default List<String> getStringsOrNull(@NotNull String path,
+                                          boolean format) {
+        return getStringsOrNull(path, format, StringUtils.FormatOption.WITH_PLACEHOLDERS);
+    }
+
+    /**
+     * Get a list of strings from config.
+     *
+     * @param path   The key to fetch the value from.
+     * @param option The format option.
+     * @return The found value, or null if not found.
+     * @deprecated Use {@link Config#getFormattedStringsOrNull(String, StringUtils.FormatOption)} instead.
+     */
+    @Nullable
+    @Deprecated
+    default List<String> getStringsOrNull(@NotNull String path,
+                                          @NotNull StringUtils.FormatOption option) {
+        return getStringsOrNull(path, false, option);
+    }
+
+    /**
+     * Get a list of strings from config.
+     *
+     * @param path   The key to fetch the value from.
+     * @param format If the strings should be formatted.
+     * @param option The format option.
+     * @return The found value, or null if not found.
      */
     @Nullable
     List<String> getStringsOrNull(@NotNull String path,
-                                  boolean format);
+                                  boolean format,
+                                  @NotNull StringUtils.FormatOption option);
 
     /**
      * Get a decimal from config.
@@ -246,7 +540,31 @@ public interface Config extends Cloneable {
      * @param path The key to fetch the value from.
      * @return The found value, or 0 if not found.
      */
-    double getDouble(@NotNull String path);
+    default double getDouble(@NotNull String path) {
+        return Objects.requireNonNullElse(getDoubleOrNull(path), 0.0);
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path The key to fetch the value from.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default double getDoubleFromExpression(@NotNull String path) {
+        return getDoubleFromExpression(path, null);
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path   The key to fetch the value from.
+     * @param player The player to evaluate placeholders with respect to.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default double getDoubleFromExpression(@NotNull String path,
+                                           @Nullable Player player) {
+        return NumberUtils.evaluateExpression(this.getString(path), player);
+    }
 
     /**
      * Get a decimal from config.
@@ -264,7 +582,9 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<Double> getDoubles(@NotNull String path);
+    default List<Double> getDoubles(@NotNull String path) {
+        return Objects.requireNonNullElse(getDoublesOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of decimals from config.
@@ -275,6 +595,34 @@ public interface Config extends Cloneable {
     @Nullable
     List<Double> getDoublesOrNull(@NotNull String path);
 
+    /**
+     * Get a list of subsections from config.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or a blank {@link java.util.ArrayList} if not found.
+     */
+    @NotNull
+    default List<? extends Config> getSubsections(@NotNull String path) {
+        return Objects.requireNonNullElse(getSubsectionsOrNull(path), new ArrayList<>());
+    }
+
+    /**
+     * Get a list of subsections from config.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or null if not found.
+     */
+    @Nullable
+    List<? extends Config> getSubsectionsOrNull(@NotNull String path);
+
+    /**
+     * Get config type.
+     *
+     * @return The type.
+     */
+    @NotNull
+    ConfigType getType();
+
     /**
      * Clone the config.
      *

eco-api/src/main/java/com/willfp/eco/core/config/interfaces/JSONConfig.java

@@ -3,13 +3,19 @@ package com.willfp.eco.core.config.interfaces;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 /**
- * JSON configs have extra methods compared to yaml configs.
+ * JSON config.
- * <p>
+ *
- * If you need to use them, then use JSONConfig instead.
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
+@SuppressWarnings("DeprecatedIsStillUsed")
 public interface JSONConfig extends Config {
     /**
      * Get a list of subsections from config.
@@ -18,7 +24,9 @@ public interface JSONConfig extends Config {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<JSONConfig> getSubsections(@NotNull String path);
+    default List<JSONConfig> getSubsections(@NotNull String path) {
+        return Objects.requireNonNullElse(getSubsectionsOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of subsections from config.
@@ -29,6 +37,27 @@ public interface JSONConfig extends Config {
     @Nullable
     List<JSONConfig> getSubsectionsOrNull(@NotNull String path);
 
+
+    /**
+     * Get subsection from config.
+     *
+     * @param path The key to check.
+     * @return The subsection. Throws NPE if not found.
+     */
+    @Override
+    @NotNull
+    JSONConfig getSubsection(@NotNull String path);
+
+    /**
+     * Get subsection from config.
+     *
+     * @param path The key to check.
+     * @return The subsection, or null if not found.
+     */
+    @Override
+    @Nullable
+    JSONConfig getSubsectionOrNull(@NotNull String path);
+
     @Override
     JSONConfig clone();
 }

eco-api/src/main/java/com/willfp/eco/core/config/interfaces/LoadableConfig.java

@@ -1,12 +1,16 @@
 package com.willfp.eco.core.config.interfaces;
 
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.bukkit.plugin.java.JavaPlugin;
+import org.jetbrains.annotations.Nullable;
+
 import java.io.File;
 import java.io.IOException;
 
 /**
  * Interface for configs that physically exist as files in plugins.
  */
-public interface LoadableConfig {
+public interface LoadableConfig extends Config {
     /**
      * Create the file.
      */
@@ -34,9 +38,23 @@ public interface LoadableConfig {
     File getConfigFile();
 
     /**
-     * Get the config name (including extension)
+     * Get the config name (including extension).
      *
      * @return The name.
      */
     String getName();
+
+    /**
+     * Get bukkit {@link YamlConfiguration}.
+     * <p>
+     * This method is not recommended unless absolutely required as it
+     * only returns true if the type of config is {@link com.willfp.eco.core.config.ConfigType#YAML},
+     * and if the handle is an {@link YamlConfiguration} specifically. This depends on the internals
+     * and the implementation, and so may cause problems - it exists mostly for parity with
+     * {@link JavaPlugin#getConfig()}.
+     *
+     * @return The config, or null if config is not yaml-based.
+     */
+    @Nullable
+    YamlConfiguration getBukkitHandle();
 }

eco-api/src/main/java/com/willfp/eco/core/config/interfaces/WrappedYamlConfiguration.java

@@ -5,8 +5,12 @@ import org.bukkit.configuration.file.YamlConfiguration;
 /**
  * Interface for configs that wrap an {@link YamlConfiguration}.
  *
- * @see com.willfp.eco.core.config.yaml.wrapper.YamlConfigWrapper
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
+@SuppressWarnings("DeprecatedIsStillUsed")
 public interface WrappedYamlConfiguration {
     /**
      * Get the ConfigurationSection handle.

eco-api/src/main/java/com/willfp/eco/core/config/json/JSONBaseConfig.java

@@ -0,0 +1,90 @@
+package com.willfp.eco.core.config.json;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.ConfigType;
+import com.willfp.eco.core.config.interfaces.JSONConfig;
+import com.willfp.eco.core.config.json.wrapper.LoadableJSONConfigWrapper;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Config implementation for configs present in the plugin's base directory (eg config.json).
+ * <p>
+ * Automatically updates.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
+ */
+@Deprecated(since = "6.17.0")
+public abstract class JSONBaseConfig extends LoadableJSONConfigWrapper {
+    /**
+     * @param configName      The name of the config
+     * @param removeUnused    Whether keys not present in the default config should be removed on update.
+     * @param plugin          The plugin.
+     * @param updateBlacklist Substring of keys to not add/remove keys for.
+     */
+    protected JSONBaseConfig(@NotNull final String configName,
+                             final boolean removeUnused,
+                             @NotNull final PluginLike plugin,
+                             @NotNull final String... updateBlacklist) {
+        super(
+                (JSONConfig)
+                        Eco.getHandler().getConfigFactory().createUpdatableConfig(
+                                configName,
+                                plugin,
+                                "",
+                                plugin.getClass(),
+                                removeUnused,
+                                ConfigType.JSON,
+                                updateBlacklist
+                        )
+        );
+    }
+
+    /**
+     * @param configName   The name of the config
+     * @param removeUnused Whether keys not present in the default config should be removed on update.
+     * @param plugin       The plugin.
+     */
+    protected JSONBaseConfig(@NotNull final String configName,
+                             final boolean removeUnused,
+                             @NotNull final PluginLike plugin) {
+        super(
+                (JSONConfig)
+                        Eco.getHandler().getConfigFactory().createUpdatableConfig(
+                                configName,
+                                plugin,
+                                "",
+                                plugin.getClass(),
+                                removeUnused,
+                                ConfigType.JSON
+                        )
+        );
+    }
+
+    /**
+     * @param configName      The name of the config
+     * @param removeUnused    Whether keys not present in the default config should be removed on update.
+     * @param plugin          The plugin.
+     * @param updateBlacklist Substring of keys to not add/remove keys for.
+     */
+    protected JSONBaseConfig(@NotNull final String configName,
+                             final boolean removeUnused,
+                             @NotNull final EcoPlugin plugin,
+                             @NotNull final String... updateBlacklist) {
+        this(configName, removeUnused, (PluginLike) plugin, updateBlacklist);
+    }
+
+    /**
+     * @param configName   The name of the config
+     * @param removeUnused Whether keys not present in the default config should be removed on update.
+     * @param plugin       The plugin.
+     */
+    protected JSONBaseConfig(@NotNull final String configName,
+                             final boolean removeUnused,
+                             @NotNull final EcoPlugin plugin) {
+        this(configName, removeUnused, (PluginLike) plugin);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/config/json/JSONExtendableConfig.java

@@ -0,0 +1,70 @@
+package com.willfp.eco.core.config.json;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.ConfigType;
+import com.willfp.eco.core.config.interfaces.JSONConfig;
+import com.willfp.eco.core.config.json.wrapper.LoadableJSONConfigWrapper;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Config implementation for configs present in one of two places:
+ * <ul>
+ *     <li>Plugin base directory (eg config.yml, lang.yml)</li>
+ *     <li>Other extension's configs</li>
+ * </ul>
+ * <p>
+ * Automatically updates.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
+ */
+@Deprecated(since = "6.17.0")
+public abstract class JSONExtendableConfig extends LoadableJSONConfigWrapper {
+    /**
+     * @param configName       The name of the config
+     * @param removeUnused     Whether keys not present in the default config should be removed on update.
+     * @param plugin           The plugin.
+     * @param updateBlacklist  Substring of keys to not add/remove keys for.
+     * @param subDirectoryPath The subdirectory path.
+     * @param source           The class that owns the resource.
+     */
+    protected JSONExtendableConfig(@NotNull final String configName,
+                                   final boolean removeUnused,
+                                   @NotNull final PluginLike plugin,
+                                   @NotNull final Class<?> source,
+                                   @NotNull final String subDirectoryPath,
+                                   @NotNull final String... updateBlacklist) {
+        super(
+                (JSONConfig)
+                        Eco.getHandler().getConfigFactory().createUpdatableConfig(
+                                configName,
+                                plugin,
+                                subDirectoryPath,
+                                source,
+                                removeUnused,
+                                ConfigType.JSON,
+                                updateBlacklist
+                        )
+        );
+    }
+
+    /**
+     * @param configName       The name of the config
+     * @param removeUnused     Whether keys not present in the default config should be removed on update.
+     * @param plugin           The plugin.
+     * @param updateBlacklist  Substring of keys to not add/remove keys for.
+     * @param subDirectoryPath The subdirectory path.
+     * @param source           The class that owns the resource.
+     */
+    protected JSONExtendableConfig(@NotNull final String configName,
+                                   final boolean removeUnused,
+                                   @NotNull final EcoPlugin plugin,
+                                   @NotNull final Class<?> source,
+                                   @NotNull final String subDirectoryPath,
+                                   @NotNull final String... updateBlacklist) {
+        this(configName, removeUnused, (PluginLike) plugin, source, subDirectoryPath, updateBlacklist);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/config/json/JSONStaticBaseConfig.java

@@ -2,13 +2,34 @@ package com.willfp.eco.core.config.json;
 
 import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.ConfigType;
+import com.willfp.eco.core.config.interfaces.JSONConfig;
 import com.willfp.eco.core.config.json.wrapper.LoadableJSONConfigWrapper;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Non-updatable JSON config that exists within a plugin jar.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public abstract class JSONStaticBaseConfig extends LoadableJSONConfigWrapper {
+    /**
+     * Config implementation for configs present in the plugin's base directory (eg config.json, lang.json).
+     * <p>
+     * Does not automatically update.
+     *
+     * @param configName The name of the config
+     * @param plugin     The plugin.
+     */
+    protected JSONStaticBaseConfig(@NotNull final String configName,
+                                   @NotNull final PluginLike plugin) {
+        super((JSONConfig) Eco.getHandler().getConfigFactory().createLoadableConfig(configName, plugin, "", plugin.getClass(), ConfigType.JSON));
+    }
+
     /**
      * Config implementation for configs present in the plugin's base directory (eg config.json, lang.json).
      * <p>
@@ -19,6 +40,6 @@ public abstract class JSONStaticBaseConfig extends LoadableJSONConfigWrapper {
      */
     protected JSONStaticBaseConfig(@NotNull final String configName,
                                    @NotNull final EcoPlugin plugin) {
-        super(Eco.getHandler().getConfigFactory().createLoadableJSONConfig(configName, plugin, "", plugin.getClass()));
+        this(configName, (PluginLike) plugin);
     }
 }

eco-api/src/main/java/com/willfp/eco/core/config/json/JSONTransientConfig.java

@@ -1,14 +1,21 @@
 package com.willfp.eco.core.config.json;
 
 import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.config.interfaces.JSONConfig;
 import com.willfp.eco.core.config.json.wrapper.JSONConfigWrapper;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.HashMap;
 import java.util.Map;
 
 /**
  * Raw JSON config with a map of values at its core.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public class JSONTransientConfig extends JSONConfigWrapper {
     /**
      * Config implementation for passing maps.
@@ -18,6 +25,13 @@ public class JSONTransientConfig extends JSONConfigWrapper {
      * @param values The map of values.
      */
     public JSONTransientConfig(@NotNull final Map<String, Object> values) {
-        super(Eco.getHandler().getConfigFactory().createJSONConfig(values));
+        super((JSONConfig) Eco.getHandler().getConfigFactory().createConfig(values));
+    }
+
+    /**
+     * Empty JSON config.
+     */
+    public JSONTransientConfig() {
+        super((JSONConfig) Eco.getHandler().getConfigFactory().createConfig(new HashMap<>()));
     }
 }

eco-api/src/main/java/com/willfp/eco/core/config/json/wrapper/JSONConfigWrapper.java

@@ -9,7 +9,12 @@ import java.util.List;
 
 /**
  * Wrapper to handle the backend JSON config implementations.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public abstract class JSONConfigWrapper extends ConfigWrapper<JSONConfig> implements JSONConfig {
     /**
      * Create a config wrapper.
@@ -31,6 +36,16 @@ public abstract class JSONConfigWrapper extends ConfigWrapper<JSONConfig> implem
         return this.getHandle().getSubsectionsOrNull(path);
     }
 
+    @Override
+    public @NotNull JSONConfig getSubsection(@NotNull final String path) {
+        return this.getHandle().getSubsection(path);
+    }
+
+    @Override
+    public @Nullable JSONConfig getSubsectionOrNull(@NotNull final String path) {
+        return this.getHandle().getSubsectionOrNull(path);
+    }
+
     @Override
     public JSONConfig clone() {
         return this.getHandle().clone();

eco-api/src/main/java/com/willfp/eco/core/config/json/wrapper/LoadableJSONConfigWrapper.java

@@ -3,14 +3,21 @@ package com.willfp.eco.core.config.json.wrapper;
 import com.willfp.eco.core.config.interfaces.JSONConfig;
 import com.willfp.eco.core.config.interfaces.LoadableConfig;
 import org.apache.commons.lang.Validate;
+import org.bukkit.configuration.file.YamlConfiguration;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
 import java.io.IOException;
 
 /**
  * Wrapper to handle the backend loadable JSON config implementations.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public abstract class LoadableJSONConfigWrapper extends JSONConfigWrapper implements LoadableConfig {
     /**
      * Create a config wrapper.
@@ -48,4 +55,9 @@ public abstract class LoadableJSONConfigWrapper extends JSONConfigWrapper implem
     public String getName() {
         return ((LoadableConfig) this.getHandle()).getName();
     }
+
+    @Override
+    public @Nullable YamlConfiguration getBukkitHandle() {
+        return null;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/config/updating/ConfigHandler.java

@@ -4,7 +4,7 @@ import com.willfp.eco.core.config.interfaces.LoadableConfig;
 import org.jetbrains.annotations.NotNull;
 
 /**
- * Every {@link com.willfp.eco.core.EcoPlugin} has a config handler.
+ * Every {@link com.willfp.eco.core.PluginLike} has a config handler.
  * <p>
  * Handles updating and saving configs.
  */

eco-api/src/main/java/com/willfp/eco/core/config/updating/ConfigUpdater.java

@@ -23,10 +23,14 @@ import java.lang.annotation.Target;
  * <p>
  * The second:
  * <pre>{@code
- * public static void update(EcoPlugin plugin) {}
+ * public static void update(EcoPlugin plugin) {
  *     // Update code
+ * }
  * }</pre>
  * <p>
+ * If using kotlin, you have to annotate the method with {@code @JvmStatic}
+ * in order to prevent null pointer exceptions.
+ * <p>
  * Config update methods in all classes in a plugin jar will be called
  * on reload.
  * <p>

eco-api/src/main/java/com/willfp/eco/core/config/wrapper/ConfigFactory.java

@@ -1,9 +1,12 @@
 package com.willfp.eco.core.config.wrapper;
 
-import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.ConfigType;
 import com.willfp.eco.core.config.interfaces.Config;
-import com.willfp.eco.core.config.interfaces.JSONConfig;
+import com.willfp.eco.core.config.interfaces.LoadableConfig;
 import org.bukkit.configuration.file.YamlConfiguration;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Map;
@@ -11,6 +14,8 @@ import java.util.Map;
 /**
  * Internal component to create backend config implementations.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface ConfigFactory {
     /**
      * Updatable config.
@@ -20,57 +25,57 @@ public interface ConfigFactory {
      * @param subDirectoryPath The subdirectory path.
      * @param source           The class that owns the resource.
      * @param removeUnused     Whether keys not present in the default config should be removed on update.
+     * @param type             The config type.
      * @param updateBlacklist  Substring of keys to not add/remove keys for.
      * @return The config implementation.
      */
-    Config createUpdatableYamlConfig(@NotNull String configName,
+    LoadableConfig createUpdatableConfig(@NotNull String configName,
-                                     @NotNull EcoPlugin plugin,
+                                         @NotNull PluginLike plugin,
-                                     @NotNull String subDirectoryPath,
+                                         @NotNull String subDirectoryPath,
-                                     @NotNull Class<?> source,
+                                         @NotNull Class<?> source,
-                                     boolean removeUnused,
+                                         boolean removeUnused,
-                                     @NotNull String... updateBlacklist);
+                                         @NotNull ConfigType type,
+                                         @NotNull String... updateBlacklist);
 
     /**
-     * JSON loadable config.
+     * Loadable config.
      *
      * @param configName       The name of the config
      * @param plugin           The plugin.
      * @param subDirectoryPath The subdirectory path.
      * @param source           The class that owns the resource.
+     * @param type             The config type.
      * @return The config implementation.
      */
-    JSONConfig createLoadableJSONConfig(@NotNull String configName,
+    LoadableConfig createLoadableConfig(@NotNull String configName,
-                                        @NotNull EcoPlugin plugin,
+                                        @NotNull PluginLike plugin,
                                         @NotNull String subDirectoryPath,
-                                        @NotNull Class<?> source);
+                                        @NotNull Class<?> source,
+                                        @NotNull ConfigType type);
 
     /**
-     * Yaml loadable config.
+     * Create config.
-     *
-     * @param configName       The name of the config
-     * @param plugin           The plugin.
-     * @param subDirectoryPath The subdirectory path.
-     * @param source           The class that owns the resource.
-     * @return The config implementation.
-     */
-    Config createLoadableYamlConfig(@NotNull String configName,
-                                    @NotNull EcoPlugin plugin,
-                                    @NotNull String subDirectoryPath,
-                                    @NotNull Class<?> source);
-
-    /**
-     * Yaml config.
      *
      * @param config The handle.
      * @return The config implementation.
      */
-    Config createYamlConfig(@NotNull YamlConfiguration config);
+    Config createConfig(@NotNull YamlConfiguration config);
 
     /**
-     * JSON config.
+     * Create config.
      *
      * @param values The values.
      * @return The config implementation.
      */
-    JSONConfig createJSONConfig(@NotNull Map<String, Object> values);
+    Config createConfig(@NotNull Map<String, Object> values);
+
+    /**
+     * Create config.
+     *
+     * @param contents The file contents.
+     * @param type     The type.
+     * @return The config implementation.
+     */
+    Config createConfig(@NotNull String contents,
+                        @NotNull ConfigType type);
 }

eco-api/src/main/java/com/willfp/eco/core/config/wrapper/ConfigWrapper.java

@@ -1,7 +1,8 @@
 package com.willfp.eco.core.config.wrapper;
 
+import com.willfp.eco.core.config.ConfigType;
 import com.willfp.eco.core.config.interfaces.Config;
-import lombok.Getter;
+import com.willfp.eco.util.StringUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -15,6 +16,7 @@ import java.util.List;
  *
  * @param <T> The type of the handle.
  */
+@SuppressWarnings("MethodDoesntCallSuperMethod")
 public abstract class ConfigWrapper<T extends Config> implements Config {
     /**
      * Configs from eco have an internal implementation,
@@ -26,7 +28,6 @@ public abstract class ConfigWrapper<T extends Config> implements Config {
      * <p>
      * In general use, though, the handle isn't necessary.
      */
-    @Getter
     private final T handle;
 
     /**
@@ -69,109 +70,43 @@ public abstract class ConfigWrapper<T extends Config> implements Config {
         handle.set(path, object);
     }
 
-    @Override
-    public @NotNull Config getSubsection(@NotNull final String path) {
-        return handle.getSubsection(path);
-    }
-
     @Override
     public @Nullable Config getSubsectionOrNull(@NotNull final String path) {
         return handle.getSubsectionOrNull(path);
     }
 
-    @Override
-    public int getInt(@NotNull final String path) {
-        return handle.getInt(path);
-    }
-
     @Override
     public @Nullable Integer getIntOrNull(@NotNull final String path) {
         return handle.getIntOrNull(path);
     }
 
-    @Override
-    public int getInt(@NotNull final String path,
-                      final int def) {
-        return handle.getInt(path, def);
-    }
-
-    @Override
-    public @NotNull List<Integer> getInts(@NotNull final String path) {
-        return handle.getInts(path);
-    }
-
     @Override
     public @Nullable List<Integer> getIntsOrNull(@NotNull final String path) {
         return handle.getIntsOrNull(path);
     }
 
-    @Override
-    public boolean getBool(@NotNull final String path) {
-        return handle.getBool(path);
-    }
-
     @Override
     public @Nullable Boolean getBoolOrNull(@NotNull final String path) {
         return handle.getBoolOrNull(path);
     }
 
-    @Override
-    public @NotNull List<Boolean> getBools(@NotNull final String path) {
-        return handle.getBools(path);
-    }
-
     @Override
     public @Nullable List<Boolean> getBoolsOrNull(@NotNull final String path) {
         return handle.getBoolsOrNull(path);
     }
 
-    @Override
-    public @NotNull String getString(@NotNull final String path) {
-        return handle.getString(path);
-    }
-
-    @Override
-    public @NotNull String getString(@NotNull final String path,
-                                     final boolean format) {
-        return handle.getString(path, format);
-    }
-
-    @Override
-    public @Nullable String getStringOrNull(@NotNull final String path) {
-        return handle.getStringOrNull(path);
-    }
-
     @Override
     public @Nullable String getStringOrNull(@NotNull final String path,
-                                            final boolean format) {
+                                            final boolean format,
-        return handle.getStringOrNull(path, format);
+                                            @NotNull final StringUtils.FormatOption option) {
-    }
+        return handle.getStringOrNull(path, format, option);
-
-    @Override
-    public @NotNull List<String> getStrings(@NotNull final String path) {
-        return handle.getStrings(path);
-    }
-
-    @Override
-    public @NotNull List<String> getStrings(@NotNull final String path,
-                                            final boolean format) {
-        return handle.getStrings(path, format);
-    }
-
-    @Override
-    public @Nullable List<String> getStringsOrNull(@NotNull final String path) {
-        return handle.getStringsOrNull(path);
     }
 
     @Override
     public @Nullable List<String> getStringsOrNull(@NotNull final String path,
-                                                   final boolean format) {
+                                                   final boolean format,
-        return handle.getStringsOrNull(path, format);
+                                                   @NotNull final StringUtils.FormatOption option) {
-    }
+        return handle.getStringsOrNull(path, format, option);
-
-    @Override
-    public double getDouble(@NotNull final String path) {
-        return handle.getDouble(path);
     }
 
     @Override
@@ -180,17 +115,31 @@ public abstract class ConfigWrapper<T extends Config> implements Config {
     }
 
     @Override
-    public @NotNull List<Double> getDoubles(@NotNull final String path) {
+    public @Nullable List<Double> getDoublesOrNull(@NotNull final String path) {
-        return handle.getDoubles(path);
+        return handle.getDoublesOrNull(path);
     }
 
     @Override
-    public @Nullable List<Double> getDoublesOrNull(@NotNull final String path) {
+    public @Nullable List<? extends Config> getSubsectionsOrNull(@NotNull final String path) {
-        return handle.getDoublesOrNull(path);
+        return handle.getSubsectionsOrNull(path);
     }
 
     @Override
     public Config clone() {
         return handle.clone();
     }
+
+    @Override
+    public @NotNull ConfigType getType() {
+        return handle.getType();
+    }
+
+    /**
+     * Get the handle.
+     *
+     * @return The handle.
+     */
+    public T getHandle() {
+        return this.handle;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/config/wrapper/LoadableConfigWrapper.java

@@ -0,0 +1,53 @@
+package com.willfp.eco.core.config.wrapper;
+
+import com.willfp.eco.core.config.interfaces.LoadableConfig;
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.File;
+import java.io.IOException;
+
+/**
+ * Wrapper to handle the backend loadable yaml config implementations.
+ */
+public abstract class LoadableConfigWrapper extends ConfigWrapper<LoadableConfig> implements LoadableConfig {
+    /**
+     * Create a config wrapper.
+     *
+     * @param handle The handle.
+     */
+    protected LoadableConfigWrapper(@NotNull final LoadableConfig handle) {
+        super(handle);
+    }
+
+    @Override
+    public void createFile() {
+        this.getHandle().createFile();
+    }
+
+    @Override
+    public String getResourcePath() {
+        return this.getHandle().getResourcePath();
+    }
+
+    @Override
+    public void save() throws IOException {
+        this.getHandle().save();
+    }
+
+    @Override
+    public File getConfigFile() {
+        return this.getHandle().getConfigFile();
+    }
+
+    @Override
+    public String getName() {
+        return this.getHandle().getName();
+    }
+
+    @Override
+    public @Nullable YamlConfiguration getBukkitHandle() {
+        return this.getHandle().getBukkitHandle();
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/config/yaml/YamlBaseConfig.java

@@ -2,6 +2,8 @@ package com.willfp.eco.core.config.yaml;
 
 import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.ConfigType;
 import com.willfp.eco.core.config.yaml.wrapper.LoadableYamlConfigWrapper;
 import org.jetbrains.annotations.NotNull;
 
@@ -9,7 +11,12 @@ import org.jetbrains.annotations.NotNull;
  * Config implementation for configs present in the plugin's base directory (eg config.yml, lang.yml).
  * <p>
  * Automatically updates.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public abstract class YamlBaseConfig extends LoadableYamlConfigWrapper {
     /**
      * @param configName      The name of the config
@@ -19,15 +26,17 @@ public abstract class YamlBaseConfig extends LoadableYamlConfigWrapper {
      */
     protected YamlBaseConfig(@NotNull final String configName,
                              final boolean removeUnused,
-                             @NotNull final EcoPlugin plugin,
+                             @NotNull final PluginLike plugin,
                              @NotNull final String... updateBlacklist) {
         super(
-                Eco.getHandler().getConfigFactory().createUpdatableYamlConfig(
+                Eco.getHandler().getConfigFactory().createUpdatableConfig(
                         configName,
                         plugin,
                         "",
                         plugin.getClass(),
-                        removeUnused, updateBlacklist
+                        removeUnused,
+                        ConfigType.YAML,
+                        updateBlacklist
                 )
         );
     }
@@ -39,15 +48,40 @@ public abstract class YamlBaseConfig extends LoadableYamlConfigWrapper {
      */
     protected YamlBaseConfig(@NotNull final String configName,
                              final boolean removeUnused,
-                             @NotNull final EcoPlugin plugin) {
+                             @NotNull final PluginLike plugin) {
         super(
-                Eco.getHandler().getConfigFactory().createUpdatableYamlConfig(
+                Eco.getHandler().getConfigFactory().createUpdatableConfig(
                         configName,
                         plugin,
                         "",
                         plugin.getClass(),
-                        removeUnused
+                        removeUnused,
+                        ConfigType.YAML
                 )
         );
     }
+
+    /**
+     * @param configName      The name of the config
+     * @param removeUnused    Whether keys not present in the default config should be removed on update.
+     * @param plugin          The plugin.
+     * @param updateBlacklist Substring of keys to not add/remove keys for.
+     */
+    protected YamlBaseConfig(@NotNull final String configName,
+                             final boolean removeUnused,
+                             @NotNull final EcoPlugin plugin,
+                             @NotNull final String... updateBlacklist) {
+        this(configName, removeUnused, (PluginLike) plugin, updateBlacklist);
+    }
+
+    /**
+     * @param configName   The name of the config
+     * @param removeUnused Whether keys not present in the default config should be removed on update.
+     * @param plugin       The plugin.
+     */
+    protected YamlBaseConfig(@NotNull final String configName,
+                             final boolean removeUnused,
+                             @NotNull final EcoPlugin plugin) {
+        this(configName, removeUnused, (PluginLike) plugin);
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/config/yaml/YamlExtendableConfig.java

@@ -2,6 +2,8 @@ package com.willfp.eco.core.config.yaml;
 
 import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.ConfigType;
 import com.willfp.eco.core.config.yaml.wrapper.LoadableYamlConfigWrapper;
 import org.jetbrains.annotations.NotNull;
 
@@ -13,8 +15,40 @@ import org.jetbrains.annotations.NotNull;
  * </ul>
  * <p>
  * Automatically updates.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public abstract class YamlExtendableConfig extends LoadableYamlConfigWrapper {
+    /**
+     * @param configName       The name of the config
+     * @param removeUnused     Whether keys not present in the default config should be removed on update.
+     * @param plugin           The plugin.
+     * @param updateBlacklist  Substring of keys to not add/remove keys for.
+     * @param subDirectoryPath The subdirectory path.
+     * @param source           The class that owns the resource.
+     */
+    protected YamlExtendableConfig(@NotNull final String configName,
+                                   final boolean removeUnused,
+                                   @NotNull final PluginLike plugin,
+                                   @NotNull final Class<?> source,
+                                   @NotNull final String subDirectoryPath,
+                                   @NotNull final String... updateBlacklist) {
+        super(
+                Eco.getHandler().getConfigFactory().createUpdatableConfig(
+                        configName,
+                        plugin,
+                        subDirectoryPath,
+                        source,
+                        removeUnused,
+                        ConfigType.YAML,
+                        updateBlacklist
+                )
+        );
+    }
+
     /**
      * @param configName       The name of the config
      * @param removeUnused     Whether keys not present in the default config should be removed on update.
@@ -29,15 +63,6 @@ public abstract class YamlExtendableConfig extends LoadableYamlConfigWrapper {
                                    @NotNull final Class<?> source,
                                    @NotNull final String subDirectoryPath,
                                    @NotNull final String... updateBlacklist) {
-        super(
+        this(configName, removeUnused, (PluginLike) plugin, source, subDirectoryPath, updateBlacklist);
-                Eco.getHandler().getConfigFactory().createUpdatableYamlConfig(
-                        configName,
-                        plugin,
-                        subDirectoryPath,
-                        source,
-                        removeUnused,
-                        updateBlacklist
-                )
-        );
     }
 }

eco-api/src/main/java/com/willfp/eco/core/config/yaml/YamlStaticBaseConfig.java

@@ -2,13 +2,33 @@ package com.willfp.eco.core.config.yaml;
 
 import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.PluginLike;
+import com.willfp.eco.core.config.ConfigType;
 import com.willfp.eco.core.config.yaml.wrapper.LoadableYamlConfigWrapper;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Non-updatable yaml config that exists within a plugin jar.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public abstract class YamlStaticBaseConfig extends LoadableYamlConfigWrapper {
+    /**
+     * Config implementation for configs present in the plugin's base directory (eg config.yml, lang.yml).
+     * <p>
+     * Does not automatically update.
+     *
+     * @param configName The name of the config
+     * @param plugin     The plugin.
+     */
+    protected YamlStaticBaseConfig(@NotNull final String configName,
+                                   @NotNull final PluginLike plugin) {
+        super(Eco.getHandler().getConfigFactory().createLoadableConfig(configName, plugin, "", plugin.getClass(), ConfigType.YAML));
+    }
+
     /**
      * Config implementation for configs present in the plugin's base directory (eg config.yml, lang.yml).
      * <p>
@@ -19,6 +39,6 @@ public abstract class YamlStaticBaseConfig extends LoadableYamlConfigWrapper {
      */
     protected YamlStaticBaseConfig(@NotNull final String configName,
                                    @NotNull final EcoPlugin plugin) {
-        super(Eco.getHandler().getConfigFactory().createLoadableYamlConfig(configName, plugin, "", plugin.getClass()));
+        this(configName, (PluginLike) plugin);
     }
 }

eco-api/src/main/java/com/willfp/eco/core/config/yaml/YamlTransientConfig.java

@@ -1,6 +1,7 @@
 package com.willfp.eco.core.config.yaml;
 
 import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.config.ConfigType;
 import com.willfp.eco.core.config.yaml.wrapper.YamlConfigWrapper;
 import org.bukkit.configuration.file.YamlConfiguration;
 import org.jetbrains.annotations.NotNull;
@@ -11,19 +12,31 @@ import java.io.StringReader;
  * Config implementation for passing YamlConfigurations.
  * <p>
  * Does not automatically update.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public class YamlTransientConfig extends YamlConfigWrapper {
     /**
-     * @param config     The YamlConfiguration handle.
+     * @param config The YamlConfiguration handle.
      */
     public YamlTransientConfig(@NotNull final YamlConfiguration config) {
-        super(Eco.getHandler().getConfigFactory().createYamlConfig(config));
+        super(Eco.getHandler().getConfigFactory().createConfig(config));
     }
 
     /**
-     * @param contents     The contents of the config.
+     * @param contents The contents of the config.
      */
     public YamlTransientConfig(@NotNull final String contents) {
-        super(Eco.getHandler().getConfigFactory().createYamlConfig(YamlConfiguration.loadConfiguration(new StringReader(contents))));
+        super(Eco.getHandler().getConfigFactory().createConfig(contents, ConfigType.YAML));
+    }
+
+    /**
+     * Create a new empty transient config.
+     */
+    public YamlTransientConfig() {
+        super(Eco.getHandler().getConfigFactory().createConfig(YamlConfiguration.loadConfiguration(new StringReader(""))));
     }
 }

eco-api/src/main/java/com/willfp/eco/core/config/yaml/wrapper/LoadableYamlConfigWrapper.java

@@ -3,14 +3,21 @@ package com.willfp.eco.core.config.yaml.wrapper;
 import com.willfp.eco.core.config.interfaces.Config;
 import com.willfp.eco.core.config.interfaces.LoadableConfig;
 import org.apache.commons.lang.Validate;
+import org.bukkit.configuration.file.YamlConfiguration;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
 import java.io.IOException;
 
 /**
  * Wrapper to handle the backend loadable yaml config implementations.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public abstract class LoadableYamlConfigWrapper extends YamlConfigWrapper implements LoadableConfig {
     /**
      * Create a config wrapper.
@@ -48,4 +55,9 @@ public abstract class LoadableYamlConfigWrapper extends YamlConfigWrapper implem
     public String getName() {
         return ((LoadableConfig) this.getHandle()).getName();
     }
+
+    @Override
+    public @Nullable YamlConfiguration getBukkitHandle() {
+        return ((LoadableConfig) this.getHandle()).getBukkitHandle();
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/config/yaml/wrapper/YamlConfigWrapper.java

@@ -8,7 +8,12 @@ import org.jetbrains.annotations.NotNull;
 
 /**
  * Wrapper to handle the backend yaml config implementations.
+ *
+ * @deprecated JSON and yml have full parity, use configs without a prefix instead,
+ * eg {@link com.willfp.eco.core.config.TransientConfig}, {@link com.willfp.eco.core.config.BaseConfig}.
+ * These configs will be removed eventually.
  */
+@Deprecated(since = "6.17.0")
 public abstract class YamlConfigWrapper extends ConfigWrapper<Config> implements WrappedYamlConfiguration {
     /**
      * Create a config wrapper.
@@ -19,7 +24,6 @@ public abstract class YamlConfigWrapper extends ConfigWrapper<Config> implements
         super(handle);
     }
 
-
     @Override
     public YamlConfiguration getBukkitHandle() {
         return ((WrappedYamlConfiguration) this.getHandle()).getBukkitHandle();

eco-api/src/main/java/com/willfp/eco/core/data/PlayerProfile.java

@@ -0,0 +1,36 @@
+package com.willfp.eco.core.data;
+
+import com.willfp.eco.core.Eco;
+import org.bukkit.OfflinePlayer;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.UUID;
+
+/**
+ * Persistent data storage interface for players.
+ * <p>
+ * Profiles save automatically, so there is no need to save after changes.
+ */
+public interface PlayerProfile extends Profile {
+    /**
+     * Load a player profile.
+     *
+     * @param player The player.
+     * @return The profile.
+     */
+    @NotNull
+    static PlayerProfile load(@NotNull final OfflinePlayer player) {
+        return load(player.getUniqueId());
+    }
+
+    /**
+     * Load a player profile.
+     *
+     * @param uuid The player's UUID.
+     * @return The profile.
+     */
+    @NotNull
+    static PlayerProfile load(@NotNull final UUID uuid) {
+        return Eco.getHandler().getProfileHandler().load(uuid);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/data/Profile.java

@@ -0,0 +1,30 @@
+package com.willfp.eco.core.data;
+
+import com.willfp.eco.core.data.keys.PersistentDataKey;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Persistent data storage interface.
+ * <p>
+ * Profiles save automatically, so there is no need to save after changes.
+ */
+public interface Profile {
+    /**
+     * Write a key to persistent data.
+     *
+     * @param key   The key.
+     * @param value The value.
+     * @param <T>   The type of the key.
+     */
+    <T> void write(@NotNull PersistentDataKey<T> key,
+                   @NotNull T value);
+
+    /**
+     * Read a key from persistent data.
+     *
+     * @param key The key.
+     * @param <T> The type of the key.
+     * @return The value, or the default value if not found.
+     */
+    <T> @NotNull T read(@NotNull PersistentDataKey<T> key);
+}

eco-api/src/main/java/com/willfp/eco/core/data/ProfileHandler.java

@@ -0,0 +1,89 @@
+package com.willfp.eco.core.data;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.data.keys.PersistentDataKey;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Set;
+import java.util.UUID;
+
+/**
+ * API to handle profiles.
+ */
+@ApiStatus.Internal
+@Eco.HandlerComponent
+public interface ProfileHandler {
+    /**
+     * Load a player profile.
+     *
+     * @param uuid The UUID.
+     * @return The profile.
+     */
+    PlayerProfile load(@NotNull UUID uuid);
+
+    /**
+     * Load the server profile.
+     *
+     * @return The profile.
+     */
+    ServerProfile loadServerProfile();
+
+    /**
+     * Unload a player profile from memory.
+     * <p>
+     * This will not save the profile first.
+     *
+     * @param uuid The uuid.
+     */
+    void unloadPlayer(@NotNull UUID uuid);
+
+    /**
+     * Save a player profile.
+     * <p>
+     * Can run async if using MySQL.
+     *
+     * @param uuid The uuid.
+     * @deprecated Saving changes is faster and should be used. Saving a player manually is not recommended.
+     */
+    @Deprecated
+    default void savePlayer(@NotNull UUID uuid) {
+        this.saveKeysFor(uuid, PersistentDataKey.values());
+    }
+
+    /**
+     * Save keys for a player.
+     * <p>
+     * Can run async if using MySQL.
+     *
+     * @param uuid The uuid.
+     * @param keys The keys.
+     */
+    void saveKeysFor(@NotNull UUID uuid,
+                     @NotNull Set<PersistentDataKey<?>> keys);
+
+    /**
+     * Save all player data.
+     *
+     * @param async If the saving should be done asynchronously.
+     * @deprecated async is now handled automatically depending on implementation.
+     */
+    @Deprecated
+    default void saveAll(boolean async) {
+        saveAll();
+    }
+
+    /**
+     * Save all player data.
+     * <p>
+     * Can run async if using MySQL.
+     */
+    void saveAll();
+
+    /**
+     * Commit all changes to the file.
+     * <p>
+     * Does nothing if using MySQL.
+     */
+    void save();
+}

eco-api/src/main/java/com/willfp/eco/core/data/ServerProfile.java

@@ -0,0 +1,21 @@
+package com.willfp.eco.core.data;
+
+import com.willfp.eco.core.Eco;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Persistent data storage interface for servers.
+ * <p>
+ * Profiles save automatically, so there is no need to save after changes.
+ */
+public interface ServerProfile extends Profile {
+    /**
+     * Load the server profile.
+     *
+     * @return The profile.
+     */
+    @NotNull
+    static ServerProfile load() {
+        return Eco.getHandler().getProfileHandler().loadServerProfile();
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/data/keys/KeyRegistry.java

@@ -0,0 +1,24 @@
+package com.willfp.eco.core.data.keys;
+
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Set;
+
+/**
+ * API to register persistent data keys.
+ */
+public interface KeyRegistry {
+    /**
+     * Register a persistent data key to be stored.
+     *
+     * @param key The key.
+     */
+    void registerKey(@NotNull PersistentDataKey<?> key);
+
+    /**
+     * Get all registered keys.
+     *
+     * @return The keys.
+     */
+    Set<PersistentDataKey<?>> getRegisteredKeys();
+}

eco-api/src/main/java/com/willfp/eco/core/data/keys/PersistentDataKey.java

@@ -0,0 +1,91 @@
+package com.willfp.eco.core.data.keys;
+
+import com.willfp.eco.core.Eco;
+import org.bukkit.NamespacedKey;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Set;
+
+/**
+ * A persistent data key is a key with a type that can be stored about an offline player.
+ *
+ * @param <T> The type of the data.
+ */
+public class PersistentDataKey<T> {
+    /**
+     * The key of the persistent data value.
+     */
+    private final NamespacedKey key;
+
+    /**
+     * The default value for the key.
+     */
+    private final T defaultValue;
+
+    /**
+     * The persistent data key type.
+     */
+    private final PersistentDataKeyType<T> type;
+
+    /**
+     * Create a new Persistent Data Key.
+     *
+     * @param key          The key.
+     * @param type         The data type.
+     * @param defaultValue The default value.
+     */
+    public PersistentDataKey(@NotNull final NamespacedKey key,
+                             @NotNull final PersistentDataKeyType<T> type,
+                             @NotNull final T defaultValue) {
+        this.key = key;
+        this.defaultValue = defaultValue;
+        this.type = type;
+
+        Eco.getHandler().getKeyRegistry().registerKey(this);
+    }
+
+    @Override
+    public String toString() {
+        return "PersistentDataKey{"
+                + "key=" + key
+                + ", defaultValue=" + defaultValue
+                + ", type=" + type
+                + '}';
+    }
+
+    /**
+     * Get the key.
+     *
+     * @return The key.
+     */
+    public NamespacedKey getKey() {
+        return this.key;
+    }
+
+    /**
+     * Get the default value.
+     *
+     * @return The default value.
+     */
+    public T getDefaultValue() {
+        return this.defaultValue;
+    }
+
+    /**
+     * Get the data key type.
+     *
+     * @return The key type.
+     */
+    public PersistentDataKeyType<T> getType() {
+        return this.type;
+    }
+
+    /**
+     * Get all persistent data keys.
+     *
+     * @return The keys.
+     */
+    public static Set<PersistentDataKey<?>> values() {
+        return Eco.getHandler().getKeyRegistry().getRegisteredKeys();
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/data/keys/PersistentDataKeyType.java

@@ -0,0 +1,108 @@
+package com.willfp.eco.core.data.keys;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * All storable data key types.
+ *
+ * @param <T> The type.
+ */
+public final class PersistentDataKeyType<T> {
+    /**
+     * The registered key types.
+     */
+    private static final List<PersistentDataKeyType<?>> VALUES = new ArrayList<>();
+
+    /**
+     * String.
+     */
+    public static final PersistentDataKeyType<String> STRING = new PersistentDataKeyType<>(String.class, "STRING");
+
+    /**
+     * Boolean.
+     */
+    public static final PersistentDataKeyType<Boolean> BOOLEAN = new PersistentDataKeyType<>(Boolean.class, "BOOLEAN");
+
+    /**
+     * Int.
+     */
+    public static final PersistentDataKeyType<Integer> INT = new PersistentDataKeyType<>(Integer.class, "INT");
+
+    /**
+     * Double.
+     */
+    public static final PersistentDataKeyType<Double> DOUBLE = new PersistentDataKeyType<>(Double.class, "DOUBLE");
+
+    /**
+     * The class of the type.
+     */
+    private final Class<T> typeClass;
+
+    /**
+     * The name of the key type.
+     */
+    private final String name;
+
+    /**
+     * Get the class of the type.
+     *
+     * @return The class.
+     */
+    public Class<T> getTypeClass() {
+        return typeClass;
+    }
+
+    /**
+     * Get the name of the key type.
+     *
+     * @return The name.
+     */
+    public String name() {
+        return name;
+    }
+
+    /**
+     * Create new PersistentDataKeyType.
+     *
+     * @param typeClass The type class.
+     * @param name      The name.
+     */
+    private PersistentDataKeyType(@NotNull final Class<T> typeClass,
+                                  @NotNull final String name) {
+        VALUES.add(this);
+
+        this.typeClass = typeClass;
+        this.name = name;
+    }
+
+    /**
+     * Get all registered {@link PersistentDataKeyType}s.
+     *
+     * @return The registered types.
+     */
+    @NotNull
+    public static PersistentDataKeyType<?>[] values() {
+        return VALUES.toArray(new PersistentDataKeyType[0]);
+    }
+
+    /**
+     * Get a key type from a name.
+     *
+     * @param name The name.
+     * @return The type, or null if not found.
+     */
+    @Nullable
+    public static PersistentDataKeyType<?> valueOf(@NotNull final String name) {
+        for (PersistentDataKeyType<?> type : VALUES) {
+            if (type.name.equalsIgnoreCase(name)) {
+                return type;
+            }
+        }
+
+        return null;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/display/Display.java

@@ -1,54 +1,24 @@
 package com.willfp.eco.core.display;
 
-import lombok.experimental.UtilityClass;
+import org.bukkit.entity.Player;
-import org.apache.commons.lang.Validate;
-import org.bukkit.NamespacedKey;
 import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.meta.ItemMeta;
-import org.bukkit.persistence.PersistentDataContainer;
-import org.bukkit.persistence.PersistentDataType;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
-
+import org.jetbrains.annotations.Nullable;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 
 /**
  * Utility class to manage client-side item display.
  */
-@UtilityClass
+public final class Display {
-public class Display {
     /**
      * The prefix for client-side lore lines.
      */
     public static final String PREFIX = "§z";
 
     /**
-     * All registered display modules.
+     * The display handler.
      */
-    private static final Map<DisplayPriority, List<DisplayModule>> MODULES = new HashMap<>();
+    private static DisplayHandler handler = null;
-
-    /**
-     * NamespacedKey for finalizing.
-     */
-    private static NamespacedKey finalizeKey = null;
-
-    /**
-     * Register display module.
-     *
-     * @param module The module.
-     */
-    public void registerDisplayModule(@NotNull final DisplayModule module) {
-        List<DisplayModule> modules = MODULES.get(module.getPriority());
-
-        modules.removeIf(module1 -> module1.getPluginName().equalsIgnoreCase(module.getPluginName()));
-
-        modules.add(module);
-
-        MODULES.put(module.getPriority(), modules);
-    }
 
     /**
      * Display on ItemStacks.
@@ -56,37 +26,20 @@ public class Display {
      * @param itemStack The item.
      * @return The ItemStack.
      */
-    public ItemStack display(@NotNull final ItemStack itemStack) {
+    public static ItemStack display(@NotNull final ItemStack itemStack) {
-        if (!itemStack.hasItemMeta()) {
+        return display(itemStack, null);
-            return itemStack; // return early if there's no customization of the item
+    }
-        }
 
-        Map<String, Object[]> pluginVarArgs = new HashMap<>();
+    /**
-
+     * Display on ItemStacks.
-        for (DisplayPriority priority : DisplayPriority.values()) {
+     *
-            List<DisplayModule> modules = MODULES.get(priority);
+     * @param itemStack The item.
-            for (DisplayModule module : modules) {
+     * @param player    The player.
-                pluginVarArgs.put(module.getPluginName(), module.generateVarArgs(itemStack));
+     * @return The ItemStack.
-            }
+     */
-        }
+    public static ItemStack display(@NotNull final ItemStack itemStack,
-
+                                    @Nullable final Player player) {
-        revert(itemStack);
+        return handler.display(itemStack, player);
-
-        ItemMeta meta = itemStack.getItemMeta();
-
-        if (meta == null) {
-            return itemStack;
-        }
-
-        for (DisplayPriority priority : DisplayPriority.values()) {
-            List<DisplayModule> modules = MODULES.get(priority);
-            for (DisplayModule module : modules) {
-                Object[] varargs = pluginVarArgs.get(module.getPluginName());
-                module.display(itemStack, varargs);
-            }
-        }
-
-        return itemStack;
     }
 
     /**
@@ -95,8 +48,20 @@ public class Display {
      * @param itemStack The item.
      * @return The ItemStack.
      */
-    public ItemStack displayAndFinalize(@NotNull final ItemStack itemStack) {
+    public static ItemStack displayAndFinalize(@NotNull final ItemStack itemStack) {
-        return finalize(display(itemStack));
+        return finalize(display(itemStack, null));
+    }
+
+    /**
+     * Display on ItemStacks and then finalize.
+     *
+     * @param itemStack The item.
+     * @param player    The player.
+     * @return The ItemStack.
+     */
+    public static ItemStack displayAndFinalize(@NotNull final ItemStack itemStack,
+                                               @Nullable final Player player) {
+        return finalize(display(itemStack, player));
     }
 
     /**
@@ -105,36 +70,8 @@ public class Display {
      * @param itemStack The item.
      * @return The ItemStack.
      */
-    public ItemStack revert(@NotNull final ItemStack itemStack) {
+    public static ItemStack revert(@NotNull final ItemStack itemStack) {
-        if (Display.isFinalized(itemStack)) {
+        return handler.revert(itemStack);
-            unfinalize(itemStack);
-        }
-
-        if (!itemStack.hasItemMeta()) {
-            return itemStack;
-        }
-
-        ItemMeta meta = itemStack.getItemMeta();
-
-        if (meta == null) {
-            return itemStack;
-        }
-
-        List<String> lore = meta.getLore();
-
-        if (lore != null && lore.removeIf(line -> line.startsWith(Display.PREFIX))) { // only apply lore modification if needed
-            meta.setLore(lore);
-            itemStack.setItemMeta(meta);
-        }
-
-        for (DisplayPriority priority : DisplayPriority.values()) {
-            List<DisplayModule> modules = MODULES.get(priority);
-            for (DisplayModule module : modules) {
-                module.revert(itemStack);
-            }
-        }
-
-        return itemStack;
     }
 
     /**
@@ -143,22 +80,8 @@ public class Display {
      * @param itemStack The item.
      * @return The ItemStack.
      */
-    public ItemStack finalize(@NotNull final ItemStack itemStack) {
+    public static ItemStack finalize(@NotNull final ItemStack itemStack) {
-        Validate.notNull(finalizeKey, "Key cannot be null!");
+        return handler.finalize(itemStack);
-
-        if (itemStack.getType().getMaxStackSize() > 1) {
-            return itemStack;
-        }
-
-        ItemMeta meta = itemStack.getItemMeta();
-        if (meta == null) {
-            return itemStack;
-        }
-
-        PersistentDataContainer container = meta.getPersistentDataContainer();
-        container.set(finalizeKey, PersistentDataType.INTEGER, 1);
-        itemStack.setItemMeta(meta);
-        return itemStack;
     }
 
     /**
@@ -167,19 +90,8 @@ public class Display {
      * @param itemStack The item.
      * @return The ItemStack.
      */
-    public ItemStack unfinalize(@NotNull final ItemStack itemStack) {
+    public static ItemStack unfinalize(@NotNull final ItemStack itemStack) {
-        Validate.notNull(finalizeKey, "Key cannot be null!");
+        return handler.unfinalize(itemStack);
-
-        ItemMeta meta = itemStack.getItemMeta();
-
-        if (meta == null) {
-            return itemStack;
-        }
-
-        PersistentDataContainer container = meta.getPersistentDataContainer();
-        container.remove(finalizeKey);
-        itemStack.setItemMeta(meta);
-        return itemStack;
     }
 
     /**
@@ -188,32 +100,82 @@ public class Display {
      * @param itemStack The item.
      * @return If finalized.
      */
-    public boolean isFinalized(@NotNull final ItemStack itemStack) {
+    public static boolean isFinalized(@NotNull final ItemStack itemStack) {
-        Validate.notNull(finalizeKey, "Key cannot be null!");
+        return handler.isFinalized(itemStack);
-
-        ItemMeta meta = itemStack.getItemMeta();
-
-        if (meta == null) {
-            return false;
-        }
-
-        PersistentDataContainer container = meta.getPersistentDataContainer();
-        return container.has(finalizeKey, PersistentDataType.INTEGER);
     }
 
     /**
-     * Set key to be used for finalization.
+     * Register a new display module.
      *
-     * @param finalizeKey The key.
+     * @param module The module.
      */
-    @ApiStatus.Internal
+    public static void registerDisplayModule(@NotNull final DisplayModule module) {
-    public static void setFinalizeKey(@NotNull final NamespacedKey finalizeKey) {
+        handler.registerDisplayModule(module);
-        Display.finalizeKey = finalizeKey;
     }
 
-    static {
+    /**
-        for (DisplayPriority priority : DisplayPriority.values()) {
+     * Initialize the display system.
-            MODULES.put(priority, new ArrayList<>());
+     *
+     * @param handler The handler.
+     */
+    @ApiStatus.Internal
+    public static void init(@NotNull final DisplayHandler handler) {
+        if (Display.handler != null) {
+            throw new IllegalArgumentException("Already Initialized!");
+        }
+        Display.handler = handler;
+    }
+
+    /**
+     * Extremely janky method - also internal, so don't use it. <b>This method is
+     * NOT part of the API and may be removed at any time!</b>
+     * <p>
+     * This calls a display module with the specified parameters, now
+     * you might ask why I need a static java method when the DisplayHandler
+     * implementation could just call it itself? Well, kotlin doesn't really
+     * like dealing with vararg ambiguity, and so while kotlin can't figure out
+     * what is and isn't a vararg when I call display with a player, java can.
+     * <p>
+     * Because of this, I need to have this part of the code in java.
+     *
+     * <b>Don't call this method as part of your plugins!</b>
+     * <p>
+     * No, seriously - don't. This skips a bunch of checks and you'll almost
+     * definitely break something.
+     *
+     * @param module    The display module.
+     * @param itemStack The ItemStack.
+     * @param player    The player.
+     * @param args      The args.
+     */
+    @ApiStatus.Internal
+    public static void callDisplayModule(@NotNull final DisplayModule module,
+                                         @NotNull final ItemStack itemStack,
+                                         @Nullable final Player player,
+                                         @NotNull final Object... args) {
+        module.display(itemStack, args);
+        if (player != null) {
+            module.display(itemStack, player, args);
         }
     }
+
+    /**
+     * Set the display handler.
+     * <p>
+     * Internal API component, you will cause bugs if you create your own handler.
+     *
+     * @param handler The handler.
+     */
+    @ApiStatus.Internal
+    public static void setHandler(@NotNull final DisplayHandler handler) {
+        if (Display.handler != null) {
+            throw new IllegalStateException("Display already initialized!");
+        }
+
+        Display.handler = handler;
+    }
+
+    private Display() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/display/DisplayHandler.java

@@ -0,0 +1,64 @@
+package com.willfp.eco.core.display;
+
+import com.willfp.eco.core.Eco;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Interface for display implementations.
+ */
+@ApiStatus.Internal
+@Eco.HandlerComponent
+public interface DisplayHandler {
+    /**
+     * Register display module.
+     *
+     * @param module The module.
+     */
+    void registerDisplayModule(@NotNull DisplayModule module);
+
+    /**
+     * Display on ItemStacks.
+     *
+     * @param itemStack The item.
+     * @param player    The player.
+     * @return The ItemStack.
+     */
+    ItemStack display(@NotNull ItemStack itemStack,
+                      @Nullable Player player);
+
+    /**
+     * Revert on ItemStacks.
+     *
+     * @param itemStack The item.
+     * @return The ItemStack.
+     */
+    ItemStack revert(@NotNull ItemStack itemStack);
+
+    /**
+     * Finalize an ItemStacks.
+     *
+     * @param itemStack The item.
+     * @return The ItemStack.
+     */
+    ItemStack finalize(@NotNull ItemStack itemStack);
+
+    /**
+     * Unfinalize an ItemStacks.
+     *
+     * @param itemStack The item.
+     * @return The ItemStack.
+     */
+    ItemStack unfinalize(@NotNull ItemStack itemStack);
+
+    /**
+     * If an item is finalized.
+     *
+     * @param itemStack The item.
+     * @return If finalized.
+     */
+    boolean isFinalized(@NotNull ItemStack itemStack);
+}

eco-api/src/main/java/com/willfp/eco/core/display/DisplayModule.java

@@ -2,9 +2,10 @@ package com.willfp.eco.core.display;
 
 import com.willfp.eco.core.EcoPlugin;
 import com.willfp.eco.core.PluginDependent;
-import lombok.Getter;
+import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 /**
  * Class for all plugin-specific client-side item display modules.
@@ -13,7 +14,6 @@ public abstract class DisplayModule extends PluginDependent<EcoPlugin> {
     /**
      * The priority of the module.
      */
-    @Getter
     private final DisplayPriority priority;
 
     /**
@@ -34,8 +34,21 @@ public abstract class DisplayModule extends PluginDependent<EcoPlugin> {
      * @param itemStack The item.
      * @param args      Optional args for display.
      */
-    protected void display(@NotNull final ItemStack itemStack,
+    public void display(@NotNull final ItemStack itemStack,
-                           @NotNull final Object... args) {
+                        @NotNull final Object... args) {
+        // Technically optional.
+    }
+
+    /**
+     * Display an item.
+     *
+     * @param itemStack The item.
+     * @param player    The player.
+     * @param args      Optional args for display.
+     */
+    public void display(@NotNull final ItemStack itemStack,
+                        @Nullable final Player player,
+                        @NotNull final Object... args) {
         // Technically optional.
     }
 
@@ -44,7 +57,7 @@ public abstract class DisplayModule extends PluginDependent<EcoPlugin> {
      *
      * @param itemStack The item.
      */
-    protected void revert(@NotNull final ItemStack itemStack) {
+    public void revert(@NotNull final ItemStack itemStack) {
         // Technically optional.
     }
 
@@ -54,7 +67,7 @@ public abstract class DisplayModule extends PluginDependent<EcoPlugin> {
      * @param itemStack The itemStack.
      * @return The plugin-specific varargs.
      */
-    protected Object[] generateVarArgs(@NotNull final ItemStack itemStack) {
+    public Object[] generateVarArgs(@NotNull final ItemStack itemStack) {
         return new Object[0];
     }
 
@@ -66,4 +79,13 @@ public abstract class DisplayModule extends PluginDependent<EcoPlugin> {
     public final String getPluginName() {
         return super.getPlugin().getName();
     }
+
+    /**
+     * Get the display priority.
+     *
+     * @return The priority.
+     */
+    public DisplayPriority getPriority() {
+        return this.priority;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/drops/DropQueueFactory.java

@@ -1,11 +1,15 @@
 package com.willfp.eco.core.drops;
 
+import com.willfp.eco.core.Eco;
 import org.bukkit.entity.Player;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Internal component to create backend DropQueue implementations.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface DropQueueFactory {
     /**
      * Create a DropQueue.

eco-api/src/main/java/com/willfp/eco/core/drops/InternalDropQueue.java

@@ -1,7 +1,9 @@
 package com.willfp.eco.core.drops;
 
+import com.willfp.eco.core.Eco;
 import org.bukkit.Location;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Collection;
@@ -9,6 +11,8 @@ import java.util.Collection;
 /**
  * Internal interface for backend DropQueue implementations.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface InternalDropQueue {
     /**
      * Add item to queue.

eco-api/src/main/java/com/willfp/eco/core/entities/CustomEntity.java

@@ -0,0 +1,84 @@
+package com.willfp.eco.core.entities;
+
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.NamespacedKey;
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Function;
+import java.util.function.Predicate;
+
+/**
+ * A custom entity has 3 components.
+ *
+ * <ul>
+ *     <li>The key to identify it</li>
+ *     <li>The test to check if any entity is this custom entity</li>
+ *     <li>The supplier to spawn the custom {@link org.bukkit.entity.Entity}</li>
+ * </ul>
+ */
+public class CustomEntity implements TestableEntity {
+    /**
+     * The key.
+     */
+    private final NamespacedKey key;
+
+    /**
+     * The test for Entities to pass.
+     */
+    private final Predicate<@NotNull Entity> test;
+
+    /**
+     * The provider to spawn the entity.
+     */
+    private final Function<Location, Entity> provider;
+
+    /**
+     * Create a new custom entity.
+     *
+     * @param key      The entity key.
+     * @param test     The test.
+     * @param provider The provider to spawn the entity.
+     */
+    public CustomEntity(@NotNull final NamespacedKey key,
+                        @NotNull final Predicate<@NotNull Entity> test,
+                        @NotNull final Function<Location, Entity> provider) {
+        this.key = key;
+        this.test = test;
+        this.provider = provider;
+    }
+
+    @Override
+    public boolean matches(@Nullable final Entity entity) {
+        if (entity == null) {
+            return false;
+        }
+
+        return test.test(entity);
+    }
+
+    @Override
+    public Entity spawn(@NotNull final Location location) {
+        Validate.notNull(location.getWorld());
+
+        return provider.apply(location);
+    }
+
+    /**
+     * Register the entity.
+     */
+    public void register() {
+        Entities.registerCustomEntity(this.getKey(), this);
+    }
+
+    /**
+     * Get the key.
+     *
+     * @return The key.
+     */
+    public NamespacedKey getKey() {
+        return this.key;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/Entities.java

@@ -0,0 +1,239 @@
+package com.willfp.eco.core.entities;
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult;
+import com.willfp.eco.core.entities.args.EntityArgParser;
+import com.willfp.eco.core.entities.impl.EmptyTestableEntity;
+import com.willfp.eco.core.entities.impl.ModifiedTestableEntity;
+import com.willfp.eco.core.entities.impl.SimpleTestableEntity;
+import com.willfp.eco.util.NamespacedKeyUtils;
+import com.willfp.eco.util.StringUtils;
+import org.bukkit.Location;
+import org.bukkit.NamespacedKey;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.EntityType;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Function;
+
+/**
+ * Class to manage all custom and vanilla entities.
+ */
+public final class Entities {
+    /**
+     * All entities.
+     */
+    private static final Map<NamespacedKey, TestableEntity> REGISTRY = new ConcurrentHashMap<>();
+
+    /**
+     * All entity parsers.
+     */
+    private static final List<EntityArgParser> ARG_PARSERS = new ArrayList<>();
+
+    /**
+     * Register a new custom item.
+     *
+     * @param key  The key of the item.
+     * @param item The item.
+     */
+    public static void registerCustomEntity(@NotNull final NamespacedKey key,
+                                            @NotNull final TestableEntity item) {
+        REGISTRY.put(key, item);
+    }
+
+    /**
+     * Register a new arg parser.
+     *
+     * @param parser The parser.
+     */
+    public static void registerArgParser(@NotNull final EntityArgParser parser) {
+        ARG_PARSERS.add(parser);
+    }
+
+    /**
+     * Remove an entity.
+     *
+     * @param key The key of the entity.
+     */
+    public static void removeCustomEntity(@NotNull final NamespacedKey key) {
+        REGISTRY.remove(key);
+    }
+
+    /**
+     * This is the backbone of the entire eco entity system.
+     * <p>
+     * You can look up a TestableEntity for any type or custom entity,
+     * and it will return it with any modifiers passed as parameters.
+     * <p>
+     * If you want to get an Entity instance from this, then just call
+     * {@link TestableEntity#spawn(Location)}.
+     * <p>
+     * The advantages of the testable entity system are that there is the inbuilt
+     * {@link TestableEntity#matches(Entity)} - this allows to check if any entity
+     * is that testable entity; which may sound negligible, but actually it allows for
+     * much more power and flexibility. For example, you can have an entity with an
+     * extra metadata tag, extra lore lines, different display name - and it
+     * will still work as long as the test passes.
+     *
+     * @param key The lookup string.
+     * @return The testable entity, or an empty testable entity if not found.
+     */
+    @NotNull
+    public static TestableEntity lookup(@NotNull final String key) {
+        if (key.contains("?")) {
+            String[] options = key.split("\\?");
+            for (String option : options) {
+                TestableEntity lookup = lookup(option);
+                if (!(lookup instanceof EmptyTestableEntity)) {
+                    return lookup;
+                }
+            }
+
+            return new EmptyTestableEntity();
+        }
+
+        String[] args = StringUtils.parseTokens(key);
+
+        if (args.length == 0) {
+            return new EmptyTestableEntity();
+        }
+
+        TestableEntity entity;
+
+        String[] split = args[0].toLowerCase().split(":");
+
+        if (split.length == 1) {
+            EntityType type;
+            try {
+                type = EntityType.valueOf(args[0].toUpperCase());
+            } catch (IllegalArgumentException e) {
+                return new EmptyTestableEntity();
+            }
+            entity = new SimpleTestableEntity(type);
+        } else {
+            String namespace = split[0];
+            String keyID = split[1];
+            NamespacedKey namespacedKey = NamespacedKeyUtils.create(namespace, keyID);
+
+            TestableEntity part = REGISTRY.get(namespacedKey);
+
+            if (part == null) {
+                return new EmptyTestableEntity();
+            }
+
+            entity = part;
+        }
+
+
+        String[] modifierArgs = Arrays.copyOfRange(args, 1, args.length);
+
+        List<EntityArgParseResult> parseResults = new ArrayList<>();
+
+        for (EntityArgParser argParser : ARG_PARSERS) {
+            EntityArgParseResult result = argParser.parseArguments(modifierArgs);
+            if (result != null) {
+                parseResults.add(result);
+            }
+        }
+
+        Function<Location, Entity> spawner = entity::spawn;
+
+        if (!parseResults.isEmpty()) {
+            entity = new ModifiedTestableEntity(
+                    entity,
+                    test -> {
+                        for (EntityArgParseResult parseResult : parseResults) {
+                            if (!parseResult.test().test(test)) {
+                                return false;
+                            }
+                        }
+
+                        return true;
+                    },
+                    location -> {
+                        Entity spawned = spawner.apply(location);
+
+                        for (EntityArgParseResult parseResult : parseResults) {
+                            parseResult.modifier().accept(spawned);
+                        }
+
+                        return spawned;
+                    }
+            );
+        }
+
+        return entity;
+    }
+
+
+    /**
+     * Get a Testable Entity from an ItemStack.
+     * <p>
+     * Will search for registered entity first. If there are no matches in the registry,
+     * then it will return a {@link com.willfp.eco.core.entities.impl.SimpleTestableEntity} matching the entity type.
+     * <p>
+     * If the entity is not custom and has unknown type, this will return null.
+     *
+     * @param entity The Entity.
+     * @return The found Testable Entity.
+     */
+    @Nullable
+    public static TestableEntity getEntity(@Nullable final Entity entity) {
+        if (entity == null) {
+            return null;
+        }
+
+        TestableEntity customEntity = getEntity(entity);
+
+        if (customEntity != null) {
+            return customEntity;
+        }
+
+        for (TestableEntity known : REGISTRY.values()) {
+            if (known.matches(entity)) {
+                return known;
+            }
+        }
+
+        if (entity.getType() == EntityType.UNKNOWN) {
+            return null;
+        }
+
+        return new SimpleTestableEntity(entity.getType());
+    }
+
+    /**
+     * Get if entity is a custom entity.
+     *
+     * @param entity The entity to check.
+     * @return If is custom.
+     */
+    public static boolean isCustomEntity(@NotNull final Entity entity) {
+        for (TestableEntity testable : REGISTRY.values()) {
+            if (testable.matches(entity)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Get all registered custom items.
+     *
+     * @return A set of all items.
+     */
+    public static Set<TestableEntity> getCustomEntities() {
+        return new HashSet<>(REGISTRY.values());
+    }
+
+    private Entities() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/TestableEntity.java

@@ -0,0 +1,27 @@
+package com.willfp.eco.core.entities;
+
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * An item with a test to see if any item is that item.
+ */
+public interface TestableEntity {
+    /**
+     * If an Entity matches the test.
+     *
+     * @param entity The entity to test.
+     * @return If the entity matches.
+     */
+    boolean matches(@Nullable Entity entity);
+
+    /**
+     * Spawn the entity.
+     *
+     * @param location The location.
+     * @return The entity.
+     */
+    Entity spawn(@NotNull Location location);
+}

eco-api/src/main/java/com/willfp/eco/core/entities/args/EntityArgParseResult.java

@@ -0,0 +1,33 @@
+package com.willfp.eco.core.entities.args;
+
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.function.Consumer;
+import java.util.function.Predicate;
+
+/**
+ * @param test     The test for the entity.
+ * @param modifier The modifier to apply to the entity.
+ * @see EntityArgParser
+ */
+public record EntityArgParseResult(@NotNull Predicate<Entity> test,
+                                   @NotNull Consumer<Entity> modifier) {
+    /**
+     * Kotlin destructuring support.
+     *
+     * @return The test.
+     */
+    public Predicate<Entity> component1() {
+        return test;
+    }
+
+    /**
+     * Kotlin destructuring support.
+     *
+     * @return The modifier.
+     */
+    public Consumer<Entity> component2() {
+        return modifier;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/args/EntityArgParser.java

@@ -0,0 +1,20 @@
+package com.willfp.eco.core.entities.args;
+
+import com.willfp.eco.core.entities.TestableEntity;
+import org.bukkit.Location;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * An argument parser should generate the predicate as well
+ * as modify the Entity for {@link TestableEntity#spawn(Location)}.
+ */
+public interface EntityArgParser {
+    /**
+     * Parse the arguments.
+     *
+     * @param args The arguments.
+     * @return The predicate test to apply to the modified entity.
+     */
+    @Nullable EntityArgParseResult parseArguments(@NotNull String[] args);
+}

eco-api/src/main/java/com/willfp/eco/core/entities/impl/EmptyTestableEntity.java

@@ -0,0 +1,33 @@
+package com.willfp.eco.core.entities.impl;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.entities.TestableEntity;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Empty entity.
+ */
+public class EmptyTestableEntity implements TestableEntity {
+    /**
+     * Create a new empty testable entity.
+     */
+    public EmptyTestableEntity() {
+
+    }
+
+    @Override
+    public boolean matches(@Nullable final Entity entity) {
+        return false;
+    }
+
+    @Override
+    public Entity spawn(@NotNull final Location location) {
+        Validate.notNull(location.getWorld());
+
+        return Eco.getHandler().createDummyEntity(location);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/impl/ModifiedTestableEntity.java

@@ -0,0 +1,69 @@
+package com.willfp.eco.core.entities.impl;
+
+import com.willfp.eco.core.entities.TestableEntity;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Function;
+import java.util.function.Predicate;
+
+/**
+ * Existing testable entity with an extra filter.
+ *
+ * @see com.willfp.eco.core.entities.CustomEntity
+ */
+public class ModifiedTestableEntity implements TestableEntity {
+    /**
+     * The item.
+     */
+    private final TestableEntity handle;
+
+    /**
+     * The amount.
+     */
+    private final Predicate<Entity> test;
+
+    /**
+     * The provider to spawn the entity.
+     */
+    private final Function<Location, Entity> provider;
+
+    /**
+     * Create a new modified testable entity.
+     *
+     * @param entity   The base entity.
+     * @param test     The test.
+     * @param provider The provider to spawn the entity.
+     */
+    public ModifiedTestableEntity(@NotNull final TestableEntity entity,
+                                  @NotNull final Predicate<@NotNull Entity> test,
+                                  @NotNull final Function<Location, Entity> provider) {
+        this.handle = entity;
+        this.test = test;
+        this.provider = provider;
+    }
+
+    @Override
+    public boolean matches(@Nullable final Entity entity) {
+        return entity != null && handle.matches(entity) && test.test(entity);
+    }
+
+    @Override
+    public Entity spawn(@NotNull final Location location) {
+        Validate.notNull(location.getWorld());
+
+        return provider.apply(location);
+    }
+
+    /**
+     * Get the handle.
+     *
+     * @return The handle.
+     */
+    public TestableEntity getHandle() {
+        return this.handle;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/impl/SimpleTestableEntity.java

@@ -0,0 +1,53 @@
+package com.willfp.eco.core.entities.impl;
+
+import com.willfp.eco.core.entities.TestableEntity;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.EntityType;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Default vanilla entities.
+ */
+public class SimpleTestableEntity implements TestableEntity {
+    /**
+     * The entity type.
+     */
+    private final EntityType type;
+
+    /**
+     * Create a new simple testable entity.
+     *
+     * @param type The entity type.
+     */
+    public SimpleTestableEntity(@NotNull final EntityType type) {
+        this.type = type;
+
+        Validate.notNull(type.getEntityClass(), "Entity cannot be of unknown type!");
+    }
+
+    @Override
+    public boolean matches(@Nullable final Entity entity) {
+        return entity != null && entity.getType() == type;
+    }
+
+    @Override
+    public Entity spawn(@NotNull final Location location) {
+        Validate.notNull(location.getWorld());
+
+        assert type.getEntityClass() != null;
+
+        return location.getWorld().spawn(location, type.getEntityClass());
+    }
+
+    /**
+     * Get the type.
+     *
+     * @return The type.
+     */
+    public EntityType getType() {
+        return this.type;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/events/ArmorChangeEvent.java

@@ -0,0 +1,84 @@
+package com.willfp.eco.core.events;
+
+import org.bukkit.entity.Player;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.player.PlayerEvent;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+
+/**
+ * The armor change event <b>does</b> contain information about the event.
+ * <p>
+ * Unlike {@link ArmorEquipEvent}, it is called the next tick and contains previous and current armor contents.
+ */
+public class ArmorChangeEvent extends PlayerEvent {
+    /**
+     * Bukkit parity.
+     */
+    private static final HandlerList HANDLERS = new HandlerList();
+
+    /**
+     * The armor contents before. 0 is helmet, 3 is boots.
+     */
+    private final List<ItemStack> before;
+
+    /**
+     * The armor contents after. 0 is helmet, 3 is boots.
+     */
+    private final List<ItemStack> after;
+
+    /**
+     * Create a new ArmorChangeEvent.
+     *
+     * @param player The player.
+     * @param before The armor contents before.
+     * @param after  The armor contents after.
+     */
+    public ArmorChangeEvent(@NotNull final Player player,
+                            @NotNull final List<ItemStack> before,
+                            @NotNull final List<ItemStack> after) {
+        super(player);
+        this.before = before;
+        this.after = after;
+    }
+
+    /**
+     * Gets a list of handlers handling this event.
+     *
+     * @return A list of handlers handling this event.
+     */
+    @Override
+    @NotNull
+    public HandlerList getHandlers() {
+        return HANDLERS;
+    }
+
+    /**
+     * Bukkit parity.
+     *
+     * @return The handler list.
+     */
+    public static HandlerList getHandlerList() {
+        return HANDLERS;
+    }
+
+    /**
+     * Get the contents before the change.
+     *
+     * @return The contents.
+     */
+    public List<ItemStack> getBefore() {
+        return this.before;
+    }
+
+    /**
+     * Get the current contents.
+     *
+     * @return The contents.
+     */
+    public List<ItemStack> getAfter() {
+        return this.after;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/events/ArmorEquipEvent.java

@@ -13,8 +13,13 @@ import org.jetbrains.annotations.NotNull;
  * <p>
  * The event is called before the player's inventory actually updates,
  * so you can check a tick later to see the new contents.
+ *
+ * @see ArmorChangeEvent
  */
 public class ArmorEquipEvent extends PlayerEvent {
+    /**
+     * Bukkit parity.
+     */
     private static final HandlerList HANDLERS = new HandlerList();
 
     /**

eco-api/src/main/java/com/willfp/eco/core/events/DropQueuePushEvent.java

@@ -0,0 +1,143 @@
+package com.willfp.eco.core.events;
+
+import org.bukkit.Location;
+import org.bukkit.entity.Player;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.player.PlayerEvent;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Collection;
+
+/**
+ * Called on DropQueue push.
+ */
+public class DropQueuePushEvent extends PlayerEvent implements Cancellable {
+    /**
+     * Cancel state.
+     */
+    private boolean cancelled;
+
+    /**
+     * If telekinetic.
+     */
+    private final boolean isTelekinetic;
+
+    /**
+     * The items.
+     */
+    private final Collection<? extends ItemStack> items;
+
+    /**
+     * The xp.
+     */
+    private final int xp;
+
+    /**
+     * The location.
+     */
+    private final Location location;
+
+    /**
+     * Bukkit parity.
+     */
+    private static final HandlerList HANDLERS = new HandlerList();
+
+    /**
+     * Create a new DropQueuePushEvent.
+     *
+     * @param player        The player.
+     * @param items         The items.
+     * @param location      The location.
+     * @param xp            The xp.
+     * @param isTelekinetic If the event is telekinetic.
+     */
+    public DropQueuePushEvent(@NotNull final Player player,
+                              @NotNull final Collection<? extends ItemStack> items,
+                              @NotNull final Location location,
+                              final int xp,
+                              final boolean isTelekinetic) {
+        super(player);
+        this.items = items;
+        this.location = location;
+        this.xp = xp;
+        this.isTelekinetic = isTelekinetic;
+    }
+
+    /**
+     * Gets a list of handlers handling this event.
+     *
+     * @return A list of handlers handling this event.
+     */
+    @Override
+    @NotNull
+    public HandlerList getHandlers() {
+        return HANDLERS;
+    }
+
+    /**
+     * Bukkit parity.
+     *
+     * @return The handler list.
+     */
+    public static HandlerList getHandlerList() {
+        return HANDLERS;
+    }
+
+    /**
+     * Get cancel state.
+     *
+     * @return The cancel state.
+     */
+    @Override
+    public boolean isCancelled() {
+        return this.cancelled;
+    }
+
+    /**
+     * Set cancel state.
+     *
+     * @param cancelled If cancelled.
+     */
+    @Override
+    public void setCancelled(final boolean cancelled) {
+        this.cancelled = cancelled;
+    }
+
+    /**
+     * Get the items to be dropped.
+     *
+     * @return The items.
+     */
+    public Collection<? extends ItemStack> getItems() {
+        return items;
+    }
+
+    /**
+     * Get the xp to be dropped.
+     *
+     * @return The xp.
+     */
+    public int getXp() {
+        return xp;
+    }
+
+    /**
+     * Get the location.
+     *
+     * @return The location.
+     */
+    public Location getLocation() {
+        return location;
+    }
+
+    /**
+     * Get force telekinesis state.
+     *
+     * @return The force telekinesis state.
+     */
+    public boolean isTelekinetic() {
+        return this.isTelekinetic;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/events/EntityDeathByEntityEvent.java

@@ -1,6 +1,5 @@
 package com.willfp.eco.core.events;
 
-import lombok.Getter;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.LivingEntity;
 import org.bukkit.event.Event;
@@ -25,31 +24,26 @@ public class EntityDeathByEntityEvent extends Event {
     /**
      * The {@link LivingEntity} killed.
      */
-    @Getter
     private final LivingEntity victim;
 
     /**
      * The {@link Entity} that killed.
      */
-    @Getter
     private final Entity killer;
 
     /**
      * The associated {@link EntityDeathEvent}.
      */
-    @Getter
     private final EntityDeathEvent deathEvent;
 
     /**
      * The entity drops.
      */
-    @Getter
     private final List<ItemStack> drops;
 
     /**
      * The xp to drop.
      */
-    @Getter
     private final int xp;
 
     /**
@@ -91,4 +85,49 @@ public class EntityDeathByEntityEvent extends Event {
     public static HandlerList getHandlerList() {
         return HANDLERS;
     }
+
+    /**
+     * Get the entity killed.
+     *
+     * @return The victim.
+     */
+    public LivingEntity getVictim() {
+        return this.victim;
+    }
+
+    /**
+     * Get the killer.
+     *
+     * @return The killer.
+     */
+    public Entity getKiller() {
+        return this.killer;
+    }
+
+    /**
+     * Get the death event that caused this event.
+     *
+     * @return The death event.
+     */
+    public EntityDeathEvent getDeathEvent() {
+        return this.deathEvent;
+    }
+
+    /**
+     * Get the drops.
+     *
+     * @return The drops.
+     */
+    public List<ItemStack> getDrops() {
+        return this.drops;
+    }
+
+    /**
+     * Get the experience dropped.
+     *
+     * @return The experience.
+     */
+    public int getXp() {
+        return this.xp;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/events/EventManager.java

@@ -1,6 +1,7 @@
 package com.willfp.eco.core.events;
 
 import org.bukkit.event.Listener;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Manages listeners for a plugin.
@@ -11,14 +12,14 @@ public interface EventManager {
      *
      * @param listener The listener to register.
      */
-    void registerListener(Listener listener);
+    void registerListener(@NotNull Listener listener);
 
     /**
      * Unregister a listener with bukkit.
      *
      * @param listener The listener to unregister.
      */
-    void unregisterListener(Listener listener);
+    void unregisterListener(@NotNull Listener listener);
 
     /**
      * Unregister all listeners associated with the plugin.

eco-api/src/main/java/com/willfp/eco/core/events/NaturalExpGainEvent.java

@@ -1,6 +1,5 @@
 package com.willfp.eco.core.events;
 
-import lombok.Getter;
 import org.bukkit.event.Event;
 import org.bukkit.event.HandlerList;
 import org.bukkit.event.player.PlayerExpChangeEvent;
@@ -20,7 +19,6 @@ public class NaturalExpGainEvent extends Event {
      * The associated {@link PlayerExpChangeEvent}.
      * Use this to modify event parameters.
      */
-    @Getter
     private final PlayerExpChangeEvent expChangeEvent;
 
     /**
@@ -50,4 +48,13 @@ public class NaturalExpGainEvent extends Event {
     public static HandlerList getHandlerList() {
         return HANDLERS;
     }
+
+    /**
+     * Get the event that caused this event.
+     *
+     * @return The exp change event.
+     */
+    public PlayerExpChangeEvent getExpChangeEvent() {
+        return this.expChangeEvent;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/extensions/Extension.java

@@ -1,11 +1,14 @@
 package com.willfp.eco.core.extensions;
 
 import com.willfp.eco.core.EcoPlugin;
-import lombok.AccessLevel;
+import com.willfp.eco.core.PluginLike;
-import lombok.Getter;
+import com.willfp.eco.core.config.updating.ConfigHandler;
 import org.apache.commons.lang.Validate;
 import org.jetbrains.annotations.NotNull;
 
+import java.io.File;
+import java.util.logging.Logger;
+
 /**
  * An extension is a separate jar file that hooks into the base plugin jar.
  * <p>
@@ -15,13 +18,12 @@ import org.jetbrains.annotations.NotNull;
  * Syntactically, extensions are very similar to plugins in their own right, except that
  * they are loaded by another plugin.
  *
- * @see <a href="https://ecoenchants.polymart.org">EcoEnchants extension examples.</a>
+ * @see <a href="https://auxilor.polymart.org">Extension examples.</a>
  */
-public abstract class Extension {
+public abstract class Extension implements PluginLike {
     /**
      * The {@link EcoPlugin} that this extension is for.
      */
-    @Getter(AccessLevel.PROTECTED)
     private final EcoPlugin plugin;
 
     /**
@@ -53,6 +55,20 @@ public abstract class Extension {
         this.onDisable();
     }
 
+    /**
+     * Method to handle after load.
+     */
+    public final void handleAfterLoad() {
+        this.onAfterLoad();
+    }
+
+    /**
+     * Method to handle plugin reloads.
+     */
+    public final void handleReload() {
+        this.onReload();
+    }
+
     /**
      * Called on enabling Extension.
      */
@@ -63,6 +79,20 @@ public abstract class Extension {
      */
     protected abstract void onDisable();
 
+    /**
+     * Called the once the base plugin is done loading.
+     */
+    protected void onAfterLoad() {
+        // Override if needed
+    }
+
+    /**
+     * Called on plugin reload.
+     */
+    protected void onReload() {
+        // Override if needed
+    }
+
     /**
      * Set the metadata of the extension.
      * <p>
@@ -103,4 +133,28 @@ public abstract class Extension {
         Validate.notNull(metadata, "Metadata cannot be null!");
         return this.metadata.version();
     }
+
+    @Override
+    public File getDataFolder() {
+        return this.plugin.getDataFolder();
+    }
+
+    @Override
+    public ConfigHandler getConfigHandler() {
+        return this.plugin.getConfigHandler();
+    }
+
+    @Override
+    public Logger getLogger() {
+        return this.plugin.getLogger();
+    }
+
+    /**
+     * Get the plugin for the extension.
+     *
+     * @return The plugin.
+     */
+    protected EcoPlugin getPlugin() {
+        return this.plugin;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/fast/FastItemStack.java

@@ -0,0 +1,135 @@
+package com.willfp.eco.core.fast;
+
+import com.willfp.eco.core.Eco;
+import org.bukkit.Material;
+import org.bukkit.enchantments.Enchantment;
+import org.bukkit.inventory.ItemFlag;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+
+/**
+ * FastItemStack contains methods to modify and read items faster than in default bukkit.
+ */
+public interface FastItemStack {
+    /**
+     * Get all enchantments on an item.
+     *
+     * @param checkStored If stored NBT should also be checked.
+     * @return A map of all enchantments.
+     * @deprecated Poorly named method. Use getEnchants instead.
+     */
+    @Deprecated(since = "6.24.0")
+    default Map<Enchantment, Integer> getEnchantmentsOnItem(boolean checkStored) {
+        return getEnchants(checkStored);
+    }
+
+    /**
+     * Get all enchantments on an item.
+     * Does not account for stored enchants.
+     *
+     * @return A map of all enchantments.
+     */
+    default Map<Enchantment, Integer> getEnchants() {
+        return getEnchants(false);
+    }
+
+    /**
+     * Get all enchantments on an item.
+     *
+     * @param checkStored If stored enchantments should be accounted for.
+     * @return A map of all enchantments.
+     */
+    Map<Enchantment, Integer> getEnchants(boolean checkStored);
+
+    /**
+     * Get the level of an enchantment on an item.
+     *
+     * @param enchantment The enchantment.
+     * @param checkStored If the stored NBT should also be checked.
+     * @return The enchantment level, or 0 if not found.
+     */
+    int getLevelOnItem(@NotNull Enchantment enchantment,
+                       boolean checkStored);
+
+    /**
+     * Set the item lore.
+     *
+     * @param lore The lore.
+     */
+    void setLore(@Nullable List<String> lore);
+
+    /**
+     * Get the item lore.
+     *
+     * @return The lore.
+     */
+    List<String> getLore();
+
+
+    /**
+     * Set the rework penalty.
+     *
+     * @param cost The rework penalty to set.
+     */
+    void setRepairCost(int cost);
+
+    /**
+     * Get the rework penalty.
+     * .
+     *
+     * @return The rework penalty found on the item.
+     */
+    int getRepairCost();
+
+    /**
+     * Add ItemFlags.
+     *
+     * @param hideFlags The flags.
+     */
+    void addItemFlags(@NotNull ItemFlag... hideFlags);
+
+    /**
+     * Remove ItemFlags.
+     *
+     * @param hideFlags The flags.
+     */
+    void removeItemFlags(@NotNull ItemFlag... hideFlags);
+
+    /**
+     * Get the ItemFlags.
+     *
+     * @return The flags.
+     */
+    Set<ItemFlag> getItemFlags();
+
+    /**
+     * Test the item for a flag.
+     *
+     * @param flag The flag.
+     * @return If the flag is present.
+     */
+    boolean hasItemFlag(@NotNull ItemFlag flag);
+
+    /**
+     * Get the Bukkit ItemStack again.
+     *
+     * @return The ItemStack.
+     */
+    ItemStack unwrap();
+
+    /**
+     * Wrap an ItemStack to create a FastItemStack.
+     *
+     * @param itemStack The ItemStack.
+     * @return The FastItemStack.
+     */
+    static FastItemStack wrap(@Nullable final ItemStack itemStack) {
+        return Eco.getHandler().createFastItemStack(Objects.requireNonNullElseGet(itemStack, () -> new ItemStack(Material.AIR)));
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/gui/GUIFactory.java

@@ -1,17 +1,19 @@
 package com.willfp.eco.core.gui;
 
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.gui.menu.MenuBuilder;
 import com.willfp.eco.core.gui.slot.SlotBuilder;
-import org.bukkit.entity.Player;
+import com.willfp.eco.core.gui.slot.functional.SlotProvider;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.function.Function;
-
 /**
  * Internal component used by {@link com.willfp.eco.core.gui.menu.Menu#builder(int)}
  * and {@link com.willfp.eco.core.gui.slot.Slot#builder(ItemStack)}.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface GUIFactory {
     /**
      * Create slot builder.
@@ -19,7 +21,7 @@ public interface GUIFactory {
      * @param provider The provider.
      * @return The builder.
      */
-    SlotBuilder createSlotBuilder(@NotNull Function<Player, ItemStack> provider);
+    SlotBuilder createSlotBuilder(@NotNull SlotProvider provider);
 
     /**
      * Create menu builder.

eco-api/src/main/java/com/willfp/eco/core/gui/menu/CloseHandler.java

@@ -0,0 +1,19 @@
+package com.willfp.eco.core.gui.menu;
+
+import org.bukkit.event.inventory.InventoryCloseEvent;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Interface to run on menu close.
+ */
+@FunctionalInterface
+public interface CloseHandler {
+    /**
+     * Performs this operation on the given arguments.
+     *
+     * @param event The close event.
+     * @param menu  The menu.
+     */
+    void handle(@NotNull InventoryCloseEvent event,
+                @NotNull Menu menu);
+}

eco-api/src/main/java/com/willfp/eco/core/gui/menu/Menu.java

@@ -2,9 +2,16 @@ package com.willfp.eco.core.gui.menu;
 
 import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.gui.slot.Slot;
+import org.bukkit.NamespacedKey;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.Inventory;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.persistence.PersistentDataType;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+import java.util.Set;
 
 /**
  * GUI version of {@link Inventory}.
@@ -44,6 +51,51 @@ public interface Menu {
      */
     Inventory open(@NotNull Player player);
 
+    /**
+     * Get captive items.
+     *
+     * @param player The player.
+     * @return The items.
+     */
+    List<ItemStack> getCaptiveItems(@NotNull Player player);
+
+    /**
+     * Write data.
+     *
+     * @param player The player.
+     * @param key    The key.
+     * @param type   The type.
+     * @param value  The value.
+     * @param <T>    The type.
+     * @param <Z>    The type.
+     */
+    <T, Z> void writeData(@NotNull Player player,
+                          @NotNull NamespacedKey key,
+                          @NotNull PersistentDataType<T, Z> type,
+                          @NotNull Z value);
+
+    /**
+     * Read data.
+     *
+     * @param player The player.
+     * @param key    The key.
+     * @param type   The type.
+     * @param <T>    The type.
+     * @param <Z>    The type.
+     * @return The data.
+     */
+    @Nullable <T, Z> T readData(@NotNull Player player,
+                                @NotNull NamespacedKey key,
+                                @NotNull PersistentDataType<T, Z> type);
+
+    /**
+     * Get all data keys for a player.
+     *
+     * @param player The player.
+     * @return The keys.
+     */
+    Set<NamespacedKey> getKeys(@NotNull Player player);
+
     /**
      * Create a builder with a given amount of rows.
      *

eco-api/src/main/java/com/willfp/eco/core/gui/menu/MenuBuilder.java

@@ -31,6 +31,14 @@ public interface MenuBuilder {
                         int column,
                         @NotNull Slot slot);
 
+    /**
+     * Run function to modify the builder.
+     *
+     * @param modifier The modifier.
+     * @return The builder.
+     */
+    MenuBuilder modfiy(@NotNull Consumer<MenuBuilder> modifier);
+
     /**
      * Set the menu mask.
      *
@@ -45,7 +53,18 @@ public interface MenuBuilder {
      * @param action The handler.
      * @return The builder.
      */
-    MenuBuilder onClose(@NotNull Consumer<InventoryCloseEvent> action);
+    default MenuBuilder onClose(@NotNull Consumer<InventoryCloseEvent> action) {
+        onClose((event, menu) -> action.accept(event));
+        return this;
+    }
+
+    /**
+     * Set the menu close handler.
+     *
+     * @param action The handler.
+     * @return The builder.
+     */
+    MenuBuilder onClose(@NotNull CloseHandler action);
 
     /**
      * Build the menu.

eco-api/src/main/java/com/willfp/eco/core/gui/slot/FillerMask.java

@@ -1,12 +1,14 @@
 package com.willfp.eco.core.gui.slot;
 
 import com.willfp.eco.core.items.builder.ItemStackBuilder;
+import com.willfp.eco.core.recipe.parts.EmptyTestableItem;
+import com.willfp.eco.core.recipe.parts.MaterialTestableItem;
 import com.willfp.eco.util.ListUtils;
-import lombok.Getter;
 import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Arrays;
 import java.util.List;
 
 /**
@@ -28,7 +30,6 @@ public class FillerMask {
     /**
      * Mask.
      */
-    @Getter
     private final List<List<Slot>> mask;
 
     /**
@@ -39,35 +40,71 @@ public class FillerMask {
      */
     public FillerMask(@NotNull final Material material,
                       @NotNull final String... pattern) {
-        if (material == Material.AIR) {
+        this(new MaskItems(new MaterialTestableItem(material)), pattern);
-            throw new IllegalArgumentException("Material cannot be air!");
+    }
+
+    /**
+     * Create a new filler mask.
+     *
+     * @param materials The mask materials.
+     * @param pattern   The pattern.
+     * @deprecated Use {@link MaskItems} instead.
+     */
+    @Deprecated(since = "6.24.0")
+    public FillerMask(@NotNull final MaskMaterials materials,
+                      @NotNull final String... pattern) {
+        this(
+                materials.toMaskItems(),
+                pattern
+        );
+    }
+
+    /**
+     * Create a new filler mask.
+     *
+     * @param items   The mask items.
+     * @param pattern The pattern.
+     */
+    public FillerMask(@NotNull final MaskItems items,
+                      @NotNull final String... pattern) {
+        if (Arrays.stream(items.items()).anyMatch(item -> item instanceof EmptyTestableItem)) {
+            throw new IllegalArgumentException("Items cannot be empty!");
         }
 
         mask = ListUtils.create2DList(6, 9);
 
-        ItemStack itemStack = new ItemStackBuilder(material)
+        for (int i = 0; i < items.items().length; i++) {
-                .setDisplayName("&r")
+            ItemStack itemStack = new ItemStackBuilder(items.items()[i])
-                .build();
+                    .setDisplayName("&r")
+                    .build();
 
-        int row = 0;
+            int row = 0;
 
-        for (String patternRow : pattern) {
+            for (String patternRow : pattern) {
-            int column = 0;
+                int column = 0;
-            if (patternRow.length() != 9) {
+                if (patternRow.length() != 9) {
-                throw new IllegalArgumentException("Invalid amount of columns in pattern!");
+                    throw new IllegalArgumentException("Invalid amount of columns in pattern!");
-            }
-            for (char c : patternRow.toCharArray()) {
-                if (c == '0') {
-                    mask.get(row).set(column, null);
-                } else if (c == '1') {
-                    mask.get(row).set(column, new FillerSlot(itemStack));
-                } else {
-                    throw new IllegalArgumentException("Invalid character in pattern! (Must only be 0 and 1)");
                 }
+                for (char c : patternRow.toCharArray()) {
+                    if (c == '0') {
+                        mask.get(row).set(column, null);
+                    } else if (c == Character.forDigit(i + 1, 10)) {
+                        mask.get(row).set(column, new FillerSlot(itemStack));
+                    }
 
-                column++;
+                    column++;
+                }
+                row++;
             }
-            row++;
         }
     }
+
+    /**
+     * Get the mask.
+     *
+     * @return The mask.
+     */
+    public List<List<Slot>> getMask() {
+        return this.mask;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/gui/slot/FillerSlot.java

@@ -1,6 +1,5 @@
 package com.willfp.eco.core.gui.slot;
 
-import lombok.Getter;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -14,7 +13,6 @@ public class FillerSlot implements Slot {
     /**
      * The ItemStack.
      */
-    @Getter
     private final ItemStack itemStack;
 
     /**
@@ -30,4 +28,18 @@ public class FillerSlot implements Slot {
     public ItemStack getItemStack(@NotNull final Player player) {
         return itemStack;
     }
+
+    @Override
+    public boolean isCaptive() {
+        return false;
+    }
+
+    /**
+     * Get the ItemStack.
+     *
+     * @return The ItemStack.
+     */
+    public ItemStack getItemStack() {
+        return this.itemStack;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/gui/slot/MaskItems.java

@@ -0,0 +1,45 @@
+package com.willfp.eco.core.gui.slot;
+
+import com.willfp.eco.core.items.Items;
+import com.willfp.eco.core.items.TestableItem;
+import com.willfp.eco.core.recipe.parts.EmptyTestableItem;
+import com.willfp.eco.core.recipe.parts.MaterialTestableItem;
+import org.bukkit.Material;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Mask materials store a set of items which can be accessed by
+ * a filler mask.
+ *
+ * @param items The items.
+ */
+public record MaskItems(@NotNull TestableItem... items) {
+    /**
+     * Create MaskItems from a list of item names.
+     *
+     * @param names The names.
+     * @return The mask items.
+     */
+    public static MaskItems fromItemNames(@NotNull final Iterable<String> names) {
+        List<TestableItem> items = new ArrayList<>();
+
+        for (String name : names) {
+            TestableItem item = Items.lookup(name);
+
+            if (item instanceof EmptyTestableItem) {
+                continue;
+            }
+
+            items.add(item);
+        }
+
+        if (items.isEmpty()) {
+            return new MaskItems(new MaterialTestableItem(Material.BLACK_STAINED_GLASS_PANE));
+        }
+
+        return new MaskItems(items.toArray(new TestableItem[0]));
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/gui/slot/MaskMaterials.java

@@ -0,0 +1,24 @@
+package com.willfp.eco.core.gui.slot;
+
+import com.willfp.eco.core.items.Items;
+import org.bukkit.Material;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Mask materials store a set of materials which can be accessed by
+ * a filler mask.
+ *
+ * @param materials The materials.
+ * @deprecated Use {@link MaskItems} instead.
+ */
+@Deprecated(since = "6.24.0")
+public record MaskMaterials(@NotNull Material... materials) {
+    /**
+     * Convert MaskMaterials to MaskItems.
+     *
+     * @return The MaskItems.
+     */
+    public MaskItems toMaskItems() {
+        return new MaskItems(Items.fromMaterials(this.materials()));
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/gui/slot/Slot.java

@@ -1,6 +1,8 @@
 package com.willfp.eco.core.gui.slot;
 
 import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.gui.slot.functional.SlotProvider;
+import org.bukkit.Material;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -19,6 +21,22 @@ public interface Slot {
      */
     ItemStack getItemStack(@NotNull Player player);
 
+    /**
+     * If the slot is captive. (Can items be placed in it).
+     *
+     * @return If captive.
+     */
+    boolean isCaptive();
+
+    /**
+     * Create a builder for an ItemStack.
+     *
+     * @return The builder.
+     */
+    static SlotBuilder builder() {
+        return Eco.getHandler().getGUIFactory().createSlotBuilder((player, menu) -> new ItemStack(Material.AIR));
+    }
+
     /**
      * Create a builder for an ItemStack.
      *
@@ -26,7 +44,7 @@ public interface Slot {
      * @return The builder.
      */
     static SlotBuilder builder(@NotNull final ItemStack itemStack) {
-        return Eco.getHandler().getGUIFactory().createSlotBuilder(player -> itemStack);
+        return Eco.getHandler().getGUIFactory().createSlotBuilder((player, menu) -> itemStack);
     }
 
     /**
@@ -36,6 +54,16 @@ public interface Slot {
      * @return The builder.
      */
     static SlotBuilder builder(@NotNull final Function<Player, ItemStack> provider) {
+        return Eco.getHandler().getGUIFactory().createSlotBuilder((player, menu) -> provider.apply(player));
+    }
+
+    /**
+     * Create a builder for a player-specific ItemStack.
+     *
+     * @param provider The provider.
+     * @return The builder.
+     */
+    static SlotBuilder builder(@NotNull final SlotProvider provider) {
         return Eco.getHandler().getGUIFactory().createSlotBuilder(provider);
     }
 }

eco-api/src/main/java/com/willfp/eco/core/gui/slot/SlotBuilder.java

@@ -1,5 +1,8 @@
 package com.willfp.eco.core.gui.slot;
 
+import com.willfp.eco.core.gui.slot.functional.SlotHandler;
+import com.willfp.eco.core.gui.slot.functional.SlotModifier;
+import com.willfp.eco.core.gui.slot.functional.SlotUpdater;
 import org.bukkit.event.inventory.InventoryClickEvent;
 import org.jetbrains.annotations.NotNull;
 
@@ -15,7 +18,17 @@ public interface SlotBuilder {
      * @param action The handler.
      * @return The builder.
      */
-    SlotBuilder onLeftClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+    default SlotBuilder onLeftClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action) {
+        return onLeftClick((event, slot, menu) -> action.accept(event, slot));
+    }
+
+    /**
+     * Set click handler.
+     *
+     * @param handler The handler.
+     * @return The builder.
+     */
+    SlotBuilder onLeftClick(@NotNull SlotHandler handler);
 
     /**
      * Set click handler.
@@ -23,7 +36,17 @@ public interface SlotBuilder {
      * @param action The handler.
      * @return The builder.
      */
-    SlotBuilder onRightClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+    default SlotBuilder onRightClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action) {
+        return onRightClick((event, slot, menu) -> action.accept(event, slot));
+    }
+
+    /**
+     * Set click handler.
+     *
+     * @param handler The handler.
+     * @return The builder.
+     */
+    SlotBuilder onRightClick(@NotNull SlotHandler handler);
 
     /**
      * Set click handler.
@@ -31,7 +54,17 @@ public interface SlotBuilder {
      * @param action The handler.
      * @return The builder.
      */
-    SlotBuilder onShiftLeftClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+    default SlotBuilder onShiftLeftClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action) {
+        return onShiftLeftClick((event, slot, menu) -> action.accept(event, slot));
+    }
+
+    /**
+     * Set click handler.
+     *
+     * @param handler The handler.
+     * @return The builder.
+     */
+    SlotBuilder onShiftLeftClick(@NotNull SlotHandler handler);
 
     /**
      * Set click handler.
@@ -39,7 +72,17 @@ public interface SlotBuilder {
      * @param action The handler.
      * @return The builder.
      */
-    SlotBuilder onShiftRightClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+    default SlotBuilder onShiftRightClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action) {
+        return onShiftRightClick((event, slot, menu) -> action.accept(event, slot));
+    }
+
+    /**
+     * Set click handler.
+     *
+     * @param handler The handler.
+     * @return The builder.
+     */
+    SlotBuilder onShiftRightClick(@NotNull SlotHandler handler);
 
     /**
      * Set click handler.
@@ -47,7 +90,47 @@ public interface SlotBuilder {
      * @param action The handler.
      * @return The builder.
      */
-    SlotBuilder onMiddleClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action);
+    default SlotBuilder onMiddleClick(@NotNull BiConsumer<InventoryClickEvent, Slot> action) {
+        return onMiddleClick((event, slot, menu) -> action.accept(event, slot));
+    }
+
+    /**
+     * Set click handler.
+     *
+     * @param handler The handler.
+     * @return The builder.
+     */
+    SlotBuilder onMiddleClick(@NotNull SlotHandler handler);
+
+    /**
+     * Modify the ItemStack.
+     *
+     * @param modifier The modifier.
+     * @return The builder.
+     * @deprecated Use {@link SlotBuilder#setUpdater(SlotUpdater)} instead.
+     */
+    @Deprecated
+    default SlotBuilder setModifier(@NotNull SlotModifier modifier) {
+        return setUpdater((player, menu, previous) -> {
+            modifier.modify(player, menu, previous);
+            return previous;
+        });
+    }
+
+    /**
+     * Set the ItemStack updater.
+     *
+     * @param updater The updater.
+     * @return The builder.
+     */
+    SlotBuilder setUpdater(@NotNull SlotUpdater updater);
+
+    /**
+     * Set slot to be a captive slot.
+     *
+     * @return The builder.
+     */
+    SlotBuilder setCaptive();
 
     /**
      * Build the slot.

eco-api/src/main/java/com/willfp/eco/core/gui/slot/functional/SlotHandler.java

@@ -0,0 +1,23 @@
+package com.willfp.eco.core.gui.slot.functional;
+
+import com.willfp.eco.core.gui.menu.Menu;
+import com.willfp.eco.core.gui.slot.Slot;
+import org.bukkit.event.inventory.InventoryClickEvent;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Interface to run on slot click.
+ */
+@FunctionalInterface
+public interface SlotHandler {
+    /**
+     * Performs this operation on the given arguments.
+     *
+     * @param event The click event.
+     * @param slot  The slot
+     * @param menu  The menu.
+     */
+    void handle(@NotNull InventoryClickEvent event,
+                @NotNull Slot slot,
+                @NotNull Menu menu);
+}

eco-api/src/main/java/com/willfp/eco/core/gui/slot/functional/SlotModifier.java

@@ -0,0 +1,26 @@
+package com.willfp.eco.core.gui.slot.functional;
+
+import com.willfp.eco.core.gui.menu.Menu;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Interface to run on slot modify.
+ *
+ * @deprecated Use {@link SlotUpdater} instead.
+ */
+@FunctionalInterface
+@Deprecated
+public interface SlotModifier {
+    /**
+     * Performs this operation on the given arguments.
+     *
+     * @param player   The player.
+     * @param menu     The menu.
+     * @param previous The previous ItemStack.
+     */
+    void modify(@NotNull Player player,
+                @NotNull Menu menu,
+                @NotNull ItemStack previous);
+}

eco-api/src/main/java/com/willfp/eco/core/gui/slot/functional/SlotProvider.java

@@ -0,0 +1,22 @@
+package com.willfp.eco.core.gui.slot.functional;
+
+import com.willfp.eco.core.gui.menu.Menu;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Interface to run on slot display.
+ */
+@FunctionalInterface
+public interface SlotProvider {
+    /**
+     * Performs this operation on the given arguments.
+     *
+     * @param player The player.
+     * @param menu   The menu.
+     * @return The ItemStack.
+     */
+    ItemStack provide(@NotNull Player player,
+                      @NotNull Menu menu);
+}

eco-api/src/main/java/com/willfp/eco/core/gui/slot/functional/SlotUpdater.java

@@ -0,0 +1,24 @@
+package com.willfp.eco.core.gui.slot.functional;
+
+import com.willfp.eco.core.gui.menu.Menu;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Interface to run on slot update.
+ */
+@FunctionalInterface
+public interface SlotUpdater {
+    /**
+     * Performs this operation on the given arguments.
+     *
+     * @param player   The player.
+     * @param menu     The menu.
+     * @param previous The previous ItemStack.
+     * @return The new ItemStack.
+     */
+    ItemStack update(@NotNull Player player,
+                     @NotNull Menu menu,
+                     @NotNull ItemStack previous);
+}

eco-api/src/main/java/com/willfp/eco/core/integrations/IntegrationLoader.java

@@ -1,8 +1,13 @@
 package com.willfp.eco.core.integrations;
 
-import lombok.Getter;
+import org.bukkit.Bukkit;
+import org.bukkit.plugin.Plugin;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Arrays;
+import java.util.Set;
+import java.util.stream.Collectors;
+
 /**
  * An integration loader runs a runnable only if a specific plugin is present on the server.
  * <p>
@@ -10,21 +15,28 @@ import org.jetbrains.annotations.NotNull;
  */
 public class IntegrationLoader {
     /**
-     * The lambda to be ran if the plugin is present.
+     * All loaded plugins on the server.
+     */
+    private static final Set<String> LOADED_PLUGINS = Arrays.stream(Bukkit.getPluginManager().getPlugins())
+            .map(Plugin::getName)
+            .map(String::toLowerCase)
+            .collect(Collectors.toSet());
+
+    /**
+     * The lambda to be run if the plugin is present.
      */
     private final Runnable runnable;
 
     /**
      * The plugin to require to load the integration.
      */
-    @Getter
     private final String pluginName;
 
     /**
      * Create a new Integration Loader.
      *
      * @param pluginName The plugin to require.
-     * @param onLoad     The lambda to be ran if the plugin is present.
+     * @param onLoad     The lambda to be run if the plugin is present.
      */
     public IntegrationLoader(@NotNull final String pluginName,
                              @NotNull final Runnable onLoad) {
@@ -32,10 +44,28 @@ public class IntegrationLoader {
         this.pluginName = pluginName;
     }
 
+    /**
+     * Load the integration if the specified plugin is present on the server.
+     */
+    public void loadIfPresent() {
+        if (LOADED_PLUGINS.contains(this.pluginName.toLowerCase())) {
+            this.load();
+        }
+    }
+
     /**
      * Load the integration.
      */
     public void load() {
         runnable.run();
     }
+
+    /**
+     * Get the plugin name.
+     *
+     * @return The plugin name.
+     */
+    public String getPluginName() {
+        return this.pluginName;
+    }
 }