diff --git a/sources/pom.xml b/sources/pom.xml
index 6bb1cff17..d146b5a97 100644
--- a/sources/pom.xml
+++ b/sources/pom.xml
@@ -3,13 +3,13 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>akarin</artifactId>
     <packaging>jar</packaging>
-    <version>1.12.2-R0.1-SNAPSHOT</version>
+    <version>1.12.2-R0.1-RELEASE</version>
     <name>Akarin</name>
     <url>https://github.com/Akarin-project/Akarin</url>
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <api.version>unknown</api.version>
+        <api.version>1.12.2-R0.1-SNAPSHOT</api.version>
         <minecraft.version>1.12.2</minecraft.version>
         <minecraft_version>1_12_R1</minecraft_version>
         <buildtag.prefix>git-Bukkit-</buildtag.prefix>
@@ -36,7 +36,7 @@
         <dependency>
             <groupId>com.destroystokyo.paper</groupId>
             <artifactId>paper-api</artifactId>
-            <version>${project.version}</version>
+            <version>${api.version}</version>
             <scope>compile</scope>
         </dependency>
         <dependency>
diff --git a/sources/src/main/java/io/akarin/server/mixin/core/MixinMinecraftServer.java b/sources/src/main/java/io/akarin/server/mixin/core/MixinMinecraftServer.java
index e1d459a09..d203248f1 100644
--- a/sources/src/main/java/io/akarin/server/mixin/core/MixinMinecraftServer.java
+++ b/sources/src/main/java/io/akarin/server/mixin/core/MixinMinecraftServer.java
@@ -21,8 +21,6 @@ import io.akarin.server.core.AkarinGlobalConfig;
 import io.akarin.server.core.AkarinSlackScheduler;
 import net.minecraft.server.CrashReport;
 import net.minecraft.server.CustomFunctionData;
-import net.minecraft.server.Entity;
-import net.minecraft.server.EntityTameableAnimal;
 import net.minecraft.server.ITickable;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.server.MojangStatisticsGenerator;
diff --git a/sources/src/main/java/io/akarin/server/mixin/core/MixinEntityHorseAbstract.java b/sources/src/main/java/io/akarin/server/mixin/optimization/MixinEntityHorseAbstract.java
similarity index 98%
rename from sources/src/main/java/io/akarin/server/mixin/core/MixinEntityHorseAbstract.java
rename to sources/src/main/java/io/akarin/server/mixin/optimization/MixinEntityHorseAbstract.java
index 665ee6d4e..c4bfb6052 100644
--- a/sources/src/main/java/io/akarin/server/mixin/core/MixinEntityHorseAbstract.java
+++ b/sources/src/main/java/io/akarin/server/mixin/optimization/MixinEntityHorseAbstract.java
@@ -22,7 +22,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-package io.akarin.server.mixin.core;
+package io.akarin.server.mixin.optimization;
 
 import java.util.UUID;
 
diff --git a/sources/src/main/java/io/akarin/server/mixin/core/MixinEntityTameableAnimal.java b/sources/src/main/java/io/akarin/server/mixin/optimization/MixinEntityTameableAnimal.java
similarity index 98%
rename from sources/src/main/java/io/akarin/server/mixin/core/MixinEntityTameableAnimal.java
rename to sources/src/main/java/io/akarin/server/mixin/optimization/MixinEntityTameableAnimal.java
index 4f647105d..766d1461a 100644
--- a/sources/src/main/java/io/akarin/server/mixin/core/MixinEntityTameableAnimal.java
+++ b/sources/src/main/java/io/akarin/server/mixin/optimization/MixinEntityTameableAnimal.java
@@ -22,7 +22,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-package io.akarin.server.mixin.core;
+package io.akarin.server.mixin.optimization;
 
 import java.util.UUID;
 
diff --git a/sources/src/main/java/io/akarin/server/mixin/core/MixinTileEntityEnchantTable.java b/sources/src/main/java/io/akarin/server/mixin/optimization/MixinTileEntityEnchantTable.java
similarity index 86%
rename from sources/src/main/java/io/akarin/server/mixin/core/MixinTileEntityEnchantTable.java
rename to sources/src/main/java/io/akarin/server/mixin/optimization/MixinTileEntityEnchantTable.java
index 2a11d0572..b6779b0a9 100644
--- a/sources/src/main/java/io/akarin/server/mixin/core/MixinTileEntityEnchantTable.java
+++ b/sources/src/main/java/io/akarin/server/mixin/optimization/MixinTileEntityEnchantTable.java
@@ -1,4 +1,4 @@
-package io.akarin.server.mixin.core;
+package io.akarin.server.mixin.optimization;
 
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Overwrite;
diff --git a/sources/src/main/java/io/akarin/server/mixin/core/WeakBigTree.java b/sources/src/main/java/io/akarin/server/mixin/optimization/WeakBigTree.java
similarity index 95%
rename from sources/src/main/java/io/akarin/server/mixin/core/WeakBigTree.java
rename to sources/src/main/java/io/akarin/server/mixin/optimization/WeakBigTree.java
index f48952b0a..dd2ffc3f6 100644
--- a/sources/src/main/java/io/akarin/server/mixin/core/WeakBigTree.java
+++ b/sources/src/main/java/io/akarin/server/mixin/optimization/WeakBigTree.java
@@ -1,4 +1,4 @@
-package io.akarin.server.mixin.core;
+package io.akarin.server.mixin.optimization;
 
 import java.util.Random;
 
diff --git a/sources/src/main/java/io/akarin/server/mixin/core/WeakEnchantmentManager.java b/sources/src/main/java/io/akarin/server/mixin/optimization/WeakEnchantmentManager.java
similarity index 98%
rename from sources/src/main/java/io/akarin/server/mixin/core/WeakEnchantmentManager.java
rename to sources/src/main/java/io/akarin/server/mixin/optimization/WeakEnchantmentManager.java
index 406fc8e3a..4d51c79df 100644
--- a/sources/src/main/java/io/akarin/server/mixin/core/WeakEnchantmentManager.java
+++ b/sources/src/main/java/io/akarin/server/mixin/optimization/WeakEnchantmentManager.java
@@ -22,7 +22,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-package io.akarin.server.mixin.core;
+package io.akarin.server.mixin.optimization;
 
 import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
diff --git a/sources/src/main/resources/mixins.akarin.core.json b/sources/src/main/resources/mixins.akarin.core.json
index 86e5f79e4..c62008ef4 100644
--- a/sources/src/main/resources/mixins.akarin.core.json
+++ b/sources/src/main/resources/mixins.akarin.core.json
@@ -11,23 +11,24 @@
         "bootstrap.MixinMetrics",
         "bootstrap.ParallelRegistry",
         "bootstrap.MetricsBootstrap",
-        "bootstrap.MixinTimingHandler",
         
         "core.MixinMCUtil",
-        "core.WeakBigTree",
         "core.DesyncCatcher",
         "core.MixinCraftServer",
+        "core.MixinTimingHandler",
 		"core.MonsterEggGuardian",
         "core.MixinVersionCommand",
         "core.MixinMinecraftServer",
         "core.MixinChunkIOExecutor",
-        "core.WeakEnchantmentManager",
-        "core.MixinEntityHorseAbstract",
-        "core.MixinEntityTameableAnimal",
-        "core.MixinTileEntityEnchantTable",
         
         "nsc.MixinPlayerConnection",
         "nsc.OptimisticNetworkManager",
-        "nsc.NonblockingServerConnection"
+        "nsc.NonblockingServerConnection",
+        
+        "optimization.WeakBigTree",
+        "optimization.WeakEnchantmentManager",
+        "optimization.MixinEntityHorseAbstract",
+        "optimization.MixinEntityTameableAnimal",
+        "optimization.MixinTileEntityEnchantTable"
     ]
 }
\ No newline at end of file