diff --git a/src/main/java/ru/bclib/BCLib.java b/src/main/java/ru/bclib/BCLib.java
index e0936be0..d3174cae 100644
--- a/src/main/java/ru/bclib/BCLib.java
+++ b/src/main/java/ru/bclib/BCLib.java
@@ -5,6 +5,7 @@ import net.fabricmc.api.ModInitializer;
 import net.fabricmc.loader.api.FabricLoader;
 import net.minecraft.resources.ResourceLocation;
 import ru.bclib.api.TagAPI;
+import ru.bclib.api.WorldDataAPI;
 import ru.bclib.config.Configs;
 import ru.bclib.recipes.CraftingRecipes;
 import ru.bclib.registry.BaseBlockEntities;
@@ -23,6 +24,7 @@ public class BCLib implements ModInitializer {
 		BCLSurfaceBuilders.register();
 		TagAPI.init();
 		CraftingRecipes.init();
+		WorldDataAPI.registerModCache(MOD_ID);
 		Configs.save();
 	}
 	
diff --git a/src/main/java/ru/bclib/api/DataFixerAPI.java b/src/main/java/ru/bclib/api/DataFixerAPI.java
deleted file mode 100644
index e2eaff5b..00000000
--- a/src/main/java/ru/bclib/api/DataFixerAPI.java
+++ /dev/null
@@ -1,152 +0,0 @@
-package ru.bclib.api;
-
-import com.google.common.collect.Lists;
-import com.google.common.collect.Maps;
-import net.fabricmc.loader.api.FabricLoader;
-import net.fabricmc.loader.api.ModContainer;
-import net.minecraft.nbt.CompoundTag;
-import net.minecraft.nbt.ListTag;
-import net.minecraft.nbt.NbtIo;
-import net.minecraft.world.level.ChunkPos;
-import net.minecraft.world.level.chunk.storage.RegionFile;
-
-import java.io.DataInputStream;
-import java.io.DataOutputStream;
-import java.io.File;
-import java.util.Collection;
-import java.util.List;
-import java.util.Locale;
-import java.util.Map;
-
-public class DataFixerAPI {
-	private static final Map<String, String> REPLACEMENT = Maps.newHashMap();
-	private static final Map<String, Integer> FIX_VERSIONS = Maps.newHashMap();
-	
-	public static void fixData(File dir) {
-		REPLACEMENT.clear(); // API is not finished yet!
-		if (REPLACEMENT.isEmpty()) {
-			return;
-		}
-		
-		boolean shoudFix = false;
-		Collection<ModContainer> mods = FabricLoader.getInstance().getAllMods();
-		for (ModContainer mod : mods) {
-			String name = mod.getMetadata().getId();
-			int preVersion = WorldDataAPI.getIntModVersion(name);
-			int version = getModVersion(mod.getMetadata().getVersion().toString());
-			if (version > preVersion) {
-				int fixVersion = FIX_VERSIONS.getOrDefault(name, version);
-				shoudFix |= fixVersion < version && fixVersion >= preVersion;
-			}
-		}
-		;
-		if (!shoudFix) {
-			return;
-		}
-		
-		List<File> regions = getAllRegions(dir, null);
-		regions.parallelStream().forEach((file) -> {
-			try {
-				System.out.println("Fixing " + file);
-				boolean[] changed = new boolean[1];
-				RegionFile region = new RegionFile(file, file.getParentFile(), true);
-				for (int x = 0; x < 32; x++) {
-					for (int z = 0; z < 32; z++) {
-						ChunkPos pos = new ChunkPos(x, z);
-						changed[0] = false;
-						if (region.hasChunk(pos)) {
-							DataInputStream input = region.getChunkDataInputStream(pos);
-							CompoundTag root = NbtIo.read(input);
-							input.close();
-							ListTag sections = root.getCompound("Level").getList("Sections", 10);
-							sections.forEach((tag) -> {
-								ListTag palette = ((CompoundTag) tag).getList("Palette", 10);
-								palette.forEach((blockTag) -> {
-									CompoundTag blockTagCompound = ((CompoundTag) blockTag);
-									String name = blockTagCompound.getString("Name");
-									String replace = REPLACEMENT.get(name);
-									if (replace != null) {
-										blockTagCompound.putString("Name", replace);
-										changed[0] = true;
-									}
-								});
-							});
-							if (changed[0]) {
-								System.out.println("Write!");
-								DataOutputStream output = region.getChunkDataOutputStream(pos);
-								NbtIo.write(root, output);
-								output.close();
-							}
-						}
-					}
-				}
-				region.close();
-			}
-			catch (Exception e) {
-				e.printStackTrace();
-			}
-		});
-	}
-	
-	/**
-	 * Register block data fix. Fix will be applied on world load if current mod version will be newer than specified one.
-	 *
-	 * @param modID      - {@link String} mod id;
-	 * @param modVersion - {@link String} mod version, should be in format: %d.%d.%d
-	 * @param result     - {@link String} new block name;
-	 * @param names      - array of {@link String}, old block names to convert.
-	 */
-	protected static void addFix(String modID, String modVersion, String result, String... names) {
-		FIX_VERSIONS.put(modID, getModVersion(modVersion));
-		for (String name : names) {
-			REPLACEMENT.put(name, result);
-		}
-	}
-	
-	private static List<File> getAllRegions(File dir, List<File> list) {
-		if (list == null) {
-			list = Lists.newArrayList();
-		}
-		for (File file : dir.listFiles()) {
-			if (file.isDirectory()) {
-				getAllRegions(file, list);
-			}
-			else if (file.isFile() && file.getName().endsWith(".mca")) {
-				list.add(file);
-			}
-		}
-		return list;
-	}
-	
-	/**
-	 * Get mod version from string. String should be in format: %d.%d.%d
-	 *
-	 * @param version - {@link String} mod version.
-	 * @return int mod version.
-	 */
-	public static int getModVersion(String version) {
-		if (version.isEmpty()) {
-			return 0;
-		}
-		try {
-			String[] values = version.split("\\.");
-			return Integer.parseInt(values[0]) << 12 | Integer.parseInt(values[1]) << 6 | Integer.parseInt(values[2]);
-		}
-		catch (Exception e) {
-			return 0;
-		}
-	}
-	
-	/**
-	 * Get mod version from integer. String will be in format %d.%d.%d
-	 *
-	 * @param version - mod version in integer form.
-	 * @return {@link String} mod version.
-	 */
-	public static String getModVersion(int version) {
-		int a = (version >> 12) & 63;
-		int b = (version >> 6) & 63;
-		int c = version & 63;
-		return String.format(Locale.ROOT, "%d.%d.%d", a, b, c);
-	}
-}
diff --git a/src/main/java/ru/bclib/api/DataFixerAPI2.java b/src/main/java/ru/bclib/api/DataFixerAPI2.java
deleted file mode 100644
index fa660ead..00000000
--- a/src/main/java/ru/bclib/api/DataFixerAPI2.java
+++ /dev/null
@@ -1,299 +0,0 @@
-package ru.bclib.api;
-
-import net.minecraft.nbt.CompoundTag;
-import net.minecraft.nbt.ListTag;
-import net.minecraft.nbt.NbtIo;
-import net.minecraft.world.level.ChunkPos;
-import net.minecraft.world.level.chunk.storage.RegionFile;
-import org.jetbrains.annotations.NotNull;
-import ru.bclib.BCLib;
-import ru.bclib.config.Configs;
-import ru.bclib.config.PathConfig;
-import ru.bclib.config.SessionConfig;
-import ru.bclib.util.Logger;
-
-import java.io.DataInputStream;
-import java.io.DataOutputStream;
-import java.io.File;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-import java.util.function.Supplier;
-import java.util.stream.Collectors;
-
-public class DataFixerAPI2 {
-	private static final Logger LOGGER = new Logger("DataFixerAPI");
-	
-	public static void fixData(SessionConfig config) {
-		if (true || !Configs.MAIN_CONFIG.getBoolean(Configs.MAIN_PATCH_CATEGORY, "applyPatches", true)) {
-			LOGGER.info("World Patches are disabled");
-			return;
-		}
-		
-		final File dir = config.levelFolder;
-		Patch.MigrationData data = Patch.createMigrationData(config);
-		if (!data.hasAnyFixes()) {
-			LOGGER.info("Everything up to date");
-			return;
-		}
-		
-		List<File> regions = getAllRegions(dir, null);
-		regions.parallelStream().forEach((file) -> {
-			try {
-				LOGGER.info("Inspecting " + file);
-				boolean[] changed = new boolean[1];
-				RegionFile region = new RegionFile(file, file.getParentFile(), true);
-				for (int x = 0; x < 32; x++) {
-					for (int z = 0; z < 32; z++) {
-						ChunkPos pos = new ChunkPos(x, z);
-						changed[0] = false;
-						if (region.hasChunk(pos)) {
-							DataInputStream input = region.getChunkDataInputStream(pos);
-							CompoundTag root = NbtIo.read(input);
-							// if ((root.toString().contains("betternether") || root.toString().contains("bclib")) && root.toString().contains("chest")) {
-							//    NbtIo.write(root, new File(file.toString() + "-" + x + "-" + z + ".nbt"));
-							// }
-							input.close();
-							
-							ListTag tileEntities = root.getCompound("Level").getList("TileEntities", 10);
-							fixItemArrayWithID(tileEntities, changed, data, true);
-							
-							ListTag sections = root.getCompound("Level").getList("Sections", 10);
-							sections.forEach((tag) -> {
-								ListTag palette = ((CompoundTag) tag).getList("Palette", 10);
-								palette.forEach((blockTag) -> {
-									CompoundTag blockTagCompound = ((CompoundTag) blockTag);
-									changed[0] = data.replaceStringFromIDs(blockTagCompound, "Name");
-								});
-							});
-							if (changed[0]) {
-								LOGGER.warning("Writing '{}': {}/{}", file, x, z);
-								DataOutputStream output = region.getChunkDataOutputStream(pos);
-								NbtIo.write(root, output);
-								output.close();
-							}
-						}
-					}
-				}
-				region.close();
-			}
-			catch (Exception e) {
-				e.printStackTrace();
-			}
-		});
-		
-		data.markApplied();
-	}
-	
-	private static boolean fixItemArrayWithID(ListTag items, boolean[] changed, Patch.MigrationData data, boolean recursive) {
-		items.forEach(inTag -> {
-			final CompoundTag tag = (CompoundTag) inTag;
-			
-			changed[0] |= data.replaceStringFromIDs(tag, "id");
-			
-			if (recursive && tag.contains("Items")) {
-				changed[0] |= fixItemArrayWithID(tag.getList("Items", 10), changed, data, true);
-			}
-		});
-		
-		return changed[0];
-	}
-	
-	private static List<File> getAllRegions(File dir, List<File> list) {
-		if (list == null) {
-			list = new ArrayList<>();
-		}
-		for (File file : dir.listFiles()) {
-			if (file.isDirectory()) {
-				getAllRegions(file, list);
-			}
-			else if (file.isFile() && file.getName().endsWith(".mca")) {
-				list.add(file);
-			}
-		}
-		return list;
-	}
-	
-	public abstract static class Patch {
-		private static List<Patch> ALL = new ArrayList<>(10);
-		private final int level;
-		@NotNull
-		private final String modID;
-		
-		static List<Patch> getALL() {
-			return ALL;
-		}
-		
-		/**
-		 * register a new Patch
-		 *
-		 * @param patch A #Supplier that will instantiate the new Patch Object
-		 */
-		public static void registerPatch(Supplier<Patch> patch) {
-			ALL.add(patch.get());
-		}
-		
-		/**
-		 * Returns the highest patch-level that is available for the given mod. If no patches were
-		 * registerd for the mod, this will return 0
-		 *
-		 * @param modID The ID of the mod you want to query
-		 * @return The highest Patch-Level that was found
-		 */
-		public static int maxPatchLevel(@NotNull String modID) {
-			return ALL.stream().filter(p -> p.getModID().equals(modID)).mapToInt(p -> p.level).max().orElse(0);
-		}
-		
-		/**
-		 * Called by inheriting classes.
-		 * <p>
-		 * Performs some sanity checks on the values and might throw a #RuntimeException if any
-		 * inconsistencies are found.
-		 *
-		 * @param modID The ID of the Mod you want to register a patch for. This should be your
-		 *              ModID only. The ModID can not be {@code null} or an empty String.
-		 * @param level The level of the Patch. This needs to be a non-zero positive value.
-		 *              Developers are responsible for registering their patches in the correct
-		 *              order (with increasing levels). You are not allowed to register a new
-		 *              Patch with a Patch-level lower or equal than
-		 *              {@link Patch#maxPatchLevel(String)}
-		 */
-		protected Patch(@NotNull String modID, int level) {
-			//Patchlevels need to be unique and registered in ascending order
-			if (modID == null || "".equals(modID)) {
-				throw new RuntimeException("[INTERNAL ERROR] Patches need a valid modID!");
-			}
-			if (!ALL.stream()
-					.filter(p -> p.getModID().equals(modID))
-					.noneMatch(p -> p.getLevel() >= level) || level <= 0) {
-				throw new RuntimeException(
-					"[INTERNAL ERROR] Patch-levels need to be created in ascending order beginning with 1.");
-			}
-			
-			
-			BCLib.LOGGER.info(
-				"Creating Patchlevel {} ({}, {})",
-				level,
-				ALL,
-				ALL.stream().noneMatch(p -> p.getLevel() >= level)
-			);
-			this.level = level;
-			this.modID = modID;
-		}
-		
-		@Override
-		public String toString() {
-			return "Patch{" + "level=" + getModID() + ":" + getLevel() + '}';
-		}
-		
-		final public int getLevel() {
-			return level;
-		}
-		
-		/**
-		 * The Mod-ID that registered this Patch
-		 *
-		 * @return The ID
-		 */
-		final public String getModID() {
-			return modID;
-		}
-		
-		
-		/**
-		 * Return block data fixes. Fixes will be applied on world load if current patch-level for
-		 * the linked mod is lower than the {@link #level}.
-		 * <p>
-		 * The default implementation of this method returns an empty map.
-		 *
-		 * @return The returned Map should contain the replacements. All occurences of the
-		 * {@code KeySet} are replaced with the associated value.
-		 */
-		public Map<String, String> getIDReplacements() {
-			return new HashMap<String, String>();
-		}
-		
-		/**
-		 * Generates ready to use data for all currently registered patches. The list of
-		 * patches is selected by the current patch-level of the world.
-		 * <p>
-		 * A {@link #Patch} with a given {@link #level} is only included if the patch-level of the
-		 * world is less
-		 *
-		 * @return a new {@link MigrationData} Object.
-		 */
-		static MigrationData createMigrationData(PathConfig config) {
-			return new MigrationData(config);
-		}
-		
-		static class MigrationData {
-			final Set<String> mods;
-			final Map<String, String> idReplacements;
-			private final PathConfig config;
-			
-			private MigrationData(PathConfig config) {
-				this.config = config;
-				
-				this.mods = Collections.unmodifiableSet(Patch.getALL()
-															 .stream()
-															 .map(p -> p.modID)
-															 .collect(Collectors.toSet()));
-				
-				HashMap<String, String> replacements = new HashMap<String, String>();
-				for (String modID : mods) {
-					Patch.getALL().stream().filter(p -> p.modID.equals(modID)).forEach(patch -> {
-						if (currentPatchLevel(modID) < patch.level) {
-							replacements.putAll(patch.getIDReplacements());
-							LOGGER.info("Applying " + patch);
-						}
-						else {
-							LOGGER.info("Ignoring " + patch);
-						}
-					});
-				}
-				
-				this.idReplacements = Collections.unmodifiableMap(replacements);
-			}
-			
-			final public void markApplied() {
-				for (String modID : mods) {
-					LOGGER.info(
-						"Updating Patch-Level for '{}' from {} to {} -> {}",
-						modID,
-						currentPatchLevel(modID),
-						Patch.maxPatchLevel(modID),
-						config.setInt(Configs.MAIN_PATCH_CATEGORY, modID, Patch.maxPatchLevel(modID))
-					);
-				}
-				
-				config.saveChanges();
-			}
-			
-			public int currentPatchLevel(@NotNull String modID) {
-				return config.getInt(Configs.MAIN_PATCH_CATEGORY, modID, 0);
-			}
-			
-			public boolean hasAnyFixes() {
-				return idReplacements.size() > 0;
-			}
-			
-			public boolean replaceStringFromIDs(@NotNull CompoundTag tag, @NotNull String key) {
-				if (!tag.contains(key)) return false;
-				
-				final String val = tag.getString(key);
-				final String replace = idReplacements.get(val);
-				
-				if (replace != null) {
-					LOGGER.warning("Replacing ID '{}' with '{}'.", val, replace);
-					tag.putString(key, replace);
-					return true;
-				}
-				
-				return false;
-			}
-		}
-	}
-}
diff --git a/src/main/java/ru/bclib/api/WorldDataAPI.java b/src/main/java/ru/bclib/api/WorldDataAPI.java
index 842699c5..1ce22f35 100644
--- a/src/main/java/ru/bclib/api/WorldDataAPI.java
+++ b/src/main/java/ru/bclib/api/WorldDataAPI.java
@@ -7,6 +7,7 @@ import net.fabricmc.loader.api.ModContainer;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.nbt.NbtIo;
 import ru.bclib.BCLib;
+import ru.bclib.api.datafixer.DataFixerAPI;
 
 import java.io.File;
 import java.io.IOException;
@@ -24,7 +25,6 @@ public class WorldDataAPI {
 		MODS.stream().parallel().forEach(modID -> {
 			File file = new File(dataDir, modID + ".nbt");
 			CompoundTag root = new CompoundTag();
-			TAGS.put(modID, root);
 			if (file.exists()) {
 				try {
 					root = NbtIo.readCompressed(file);
@@ -38,7 +38,7 @@ public class WorldDataAPI {
 				if (optional.isPresent()) {
 					ModContainer modContainer = optional.get();
 					if (BCLib.isDevEnvironment()) {
-						root.putString("version", "63.63.63");
+						root.putString("version", "255.255.9999");
 					}
 					else {
 						root.putString("version", modContainer.getMetadata().getVersion().toString());
@@ -46,6 +46,8 @@ public class WorldDataAPI {
 					saveFile(modID);
 				}
 			}
+			
+			TAGS.put(modID, root);
 		});
 	}
 	
diff --git a/src/main/java/ru/bclib/api/datafixer/DataFixerAPI.java b/src/main/java/ru/bclib/api/datafixer/DataFixerAPI.java
new file mode 100644
index 00000000..74eae701
--- /dev/null
+++ b/src/main/java/ru/bclib/api/datafixer/DataFixerAPI.java
@@ -0,0 +1,183 @@
+package ru.bclib.api.datafixer;
+
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.ListTag;
+import net.minecraft.nbt.NbtIo;
+import net.minecraft.world.level.ChunkPos;
+import net.minecraft.world.level.chunk.storage.RegionFile;
+import ru.bclib.BCLib;
+import ru.bclib.api.WorldDataAPI;
+import ru.bclib.config.Configs;
+import ru.bclib.util.Logger;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.File;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Locale;
+import java.util.function.Supplier;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class DataFixerAPI {
+	static final Logger LOGGER = new Logger("DataFixerAPI");
+	
+	public static void fixData(File dir) {
+		if (!Configs.MAIN_CONFIG.getBoolean(Configs.MAIN_PATCH_CATEGORY, "applyPatches", true)) {
+			LOGGER.info("World Patches are disabled");
+			return;
+		}
+		
+		final CompoundTag patchConfig = WorldDataAPI.getCompoundTag(BCLib.MOD_ID, Configs.MAIN_PATCH_CATEGORY);
+		MigrationProfile data = Patch.createMigrationData(patchConfig);
+		if (!data.hasAnyFixes()) {
+			LOGGER.info("Everything up to date");
+			return;
+		}
+		
+		List<File> regions = getAllRegions(dir, null);
+		boolean[] allOk = {true};
+		regions.parallelStream()
+			   .forEach((file) -> {
+				   try {
+					   LOGGER.info("Inspecting " + file);
+					   boolean[] changed = new boolean[1];
+					   RegionFile region = new RegionFile(file, file.getParentFile(), true);
+					   for (int x = 0; x < 32; x++) {
+						   for (int z = 0; z < 32; z++) {
+							   ChunkPos pos = new ChunkPos(x, z);
+							   changed[0] = false;
+							   if (region.hasChunk(pos)) {
+								   DataInputStream input = region.getChunkDataInputStream(pos);
+								   CompoundTag root = NbtIo.read(input);
+								   // if ((root.toString().contains("betternether") || root.toString().contains("bclib")) && root.toString().contains("chest")) {
+								   //    NbtIo.write(root, new File(file.toString() + "-" + x + "-" + z + ".nbt"));
+								   // }
+								   input.close();
+							
+								   ListTag tileEntities = root.getCompound("Level")
+															  .getList("TileEntities", 10);
+								   fixItemArrayWithID(tileEntities, changed, data, true);
+							
+								   ListTag sections = root.getCompound("Level")
+														  .getList("Sections", 10);
+								   sections.forEach((tag) -> {
+									   ListTag palette = ((CompoundTag) tag).getList("Palette", 10);
+									   palette.forEach((blockTag) -> {
+										   CompoundTag blockTagCompound = ((CompoundTag) blockTag);
+										   changed[0] = data.replaceStringFromIDs(blockTagCompound, "Name");
+									   });
+								   });
+								   if (changed[0]) {
+									   LOGGER.warning("Writing '{}': {}/{}", file, x, z);
+									   DataOutputStream output = region.getChunkDataOutputStream(pos);
+									   NbtIo.write(root, output);
+									   output.close();
+								   }
+							   }
+						   }
+					   }
+					   region.close();
+				   }
+				   catch (Exception e) {
+					   allOk[0] = false;
+					   e.printStackTrace();
+				   }
+			   });
+		
+		if (allOk[0]) {
+			data.markApplied();
+			WorldDataAPI.saveFile(BCLib.MOD_ID);
+		}
+	}
+	
+	static CompoundTag patchConfTag = null;
+	static CompoundTag getPatchData(){
+		if (patchConfTag==null) {
+			patchConfTag = WorldDataAPI.getCompoundTag(BCLib.MOD_ID, Configs.MAIN_PATCH_CATEGORY);
+		}
+		return patchConfTag;
+	}
+	
+	private static boolean fixItemArrayWithID(ListTag items, boolean[] changed, MigrationProfile data, boolean recursive) {
+		items.forEach(inTag -> {
+			final CompoundTag tag = (CompoundTag) inTag;
+			
+			changed[0] |= data.replaceStringFromIDs(tag, "id");
+			
+			if (recursive && tag.contains("Items")) {
+				changed[0] |= fixItemArrayWithID(tag.getList("Items", 10), changed, data, true);
+			}
+		});
+		
+		return changed[0];
+	}
+	
+	private static List<File> getAllRegions(File dir, List<File> list) {
+		if (list == null) {
+			list = new ArrayList<>();
+		}
+		for (File file : dir.listFiles()) {
+			if (file.isDirectory()) {
+				getAllRegions(file, list);
+			}
+			else if (file.isFile() && file.getName()
+										  .endsWith(".mca")) {
+				list.add(file);
+			}
+		}
+		return list;
+	}
+	
+	/**
+	 * register a new Patch
+	 *
+	 * @param patch A #Supplier that will instantiate the new Patch Object
+	 */
+	public static void registerPatch(Supplier<Patch> patch) {
+		Patch.getALL().add(patch.get());
+	}
+	
+	/**
+	 * Get mod version from string. String should be in format: %d.%d.%d
+	 *
+	 * @param version - {@link String} mod version.
+	 * @return int mod version.
+	 */
+	public static int getModVersion(String version) {
+		if (version.isEmpty()) {
+			return 0;
+		}
+		try {
+			int res = 0;
+			final String semanticVersionPattern = "(\\d+)\\.(\\d+)\\.(\\d+)\\D*";
+			final Matcher matcher = Pattern.compile(semanticVersionPattern)
+										   .matcher(version);
+			if (matcher.find()) {
+				if (matcher.groupCount() > 0) res = (Integer.parseInt(matcher.group(1)) & 0xFF) << 22;
+				if (matcher.groupCount() > 1) res |= (Integer.parseInt(matcher.group(2)) & 0xFF) << 14;
+				if (matcher.groupCount() > 2) res |= Integer.parseInt(matcher.group(3)) & 0x3FFF;
+			}
+			
+			return res;
+		}
+		catch (Exception e) {
+			return 0;
+		}
+	}
+	
+	/**
+	 * Get mod version from integer. String will be in format %d.%d.%d
+	 *
+	 * @param version - mod version in integer form.
+	 * @return {@link String} mod version.
+	 */
+	public static String getModVersion(int version) {
+		int a = (version >> 22) & 0xFF;
+		int b = (version >> 14) & 0xFF;
+		int c = version & 0x3FFF;
+		return String.format(Locale.ROOT, "%d.%d.%d", a, b, c);
+	}
+	
+}
diff --git a/src/main/java/ru/bclib/api/datafixer/MigrationProfile.java b/src/main/java/ru/bclib/api/datafixer/MigrationProfile.java
new file mode 100644
index 00000000..644b9d6c
--- /dev/null
+++ b/src/main/java/ru/bclib/api/datafixer/MigrationProfile.java
@@ -0,0 +1,78 @@
+package ru.bclib.api.datafixer;
+
+import net.minecraft.nbt.CompoundTag;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+class MigrationProfile {
+	final Set<String> mods;
+	final Map<String, String> idReplacements;
+	private final CompoundTag config;
+	
+	MigrationProfile(CompoundTag config) {
+		this.config = config;
+		
+		this.mods = Collections.unmodifiableSet(Patch.getALL()
+													 .stream()
+													 .map(p -> p.modID)
+													 .collect(Collectors.toSet()));
+		
+		HashMap<String, String> replacements = new HashMap<String, String>();
+		for (String modID : mods) {
+			Patch.getALL()
+				 .stream()
+				 .filter(p -> p.modID.equals(modID))
+				 .forEach(patch -> {
+					 if (currentPatchLevel(modID) < patch.level) {
+						 replacements.putAll(patch.getIDReplacements());
+						 DataFixerAPI.LOGGER.info("Applying " + patch);
+					 }
+					 else {
+						 DataFixerAPI.LOGGER.info("Ignoring " + patch);
+					 }
+				 });
+		}
+		
+		this.idReplacements = Collections.unmodifiableMap(replacements);
+	}
+	
+	final public void markApplied() {
+		for (String modID : mods) {
+			DataFixerAPI.LOGGER.info("Updating Patch-Level for '{}' from {} to {}", modID, currentPatchLevel(modID), Patch.maxPatchLevel(modID));
+			config.putString(modID, Patch.maxPatchVersion(modID));
+		}
+	}
+	
+	public String currentPatchVersion(@NotNull String modID) {
+		if (!config.contains(modID)) return "0.0.0";
+		return config.getString(modID);
+	}
+	
+	public int currentPatchLevel(@NotNull String modID) {
+		return DataFixerAPI.getModVersion(currentPatchVersion(modID));
+	}
+	
+	public boolean hasAnyFixes() {
+		return idReplacements.size() > 0;
+	}
+	
+	public boolean replaceStringFromIDs(@NotNull CompoundTag tag, @NotNull String key) {
+		if (!tag.contains(key)) return false;
+		
+		final String val = tag.getString(key);
+		final String replace = idReplacements.get(val);
+		
+		if (replace != null) {
+			DataFixerAPI.LOGGER.warning("Replacing ID '{}' with '{}'.", val, replace);
+			tag.putString(key, replace);
+			return true;
+		}
+		
+		return false;
+	}
+}
diff --git a/src/main/java/ru/bclib/api/datafixer/Patch.java b/src/main/java/ru/bclib/api/datafixer/Patch.java
new file mode 100644
index 00000000..1be18145
--- /dev/null
+++ b/src/main/java/ru/bclib/api/datafixer/Patch.java
@@ -0,0 +1,135 @@
+package ru.bclib.api.datafixer;
+
+import net.minecraft.nbt.CompoundTag;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public abstract class Patch {
+	private static List<Patch> ALL = new ArrayList<>(10);
+	
+	/**
+	 * The Patch-Level derived from {@link #version}
+	 */
+	public final int level;
+	
+	/**
+	 * The Patch-Version string
+	 */
+	public final String version;
+	
+	/**
+	 * The Mod-ID that registered this Patch
+	 */
+	
+	@NotNull
+	public final String modID;
+	
+	static List<Patch> getALL() {
+		return ALL;
+	}
+	
+	/**
+	 * Returns the highest Patch-Version that is available for the given mod. If no patches were
+	 * registerd for the mod, this will return 0.0.0
+	 *
+	 * @param modID The ID of the mod you want to query
+	 * @return The highest Patch-Version that was found
+	 */
+	public static String maxPatchVersion(@NotNull String modID) {
+		return ALL.stream()
+				  .filter(p -> p.modID
+								.equals(modID))
+				  .map(p -> p.version)
+				  .reduce((p, c) -> c)
+				  .orElse("0.0.0");
+	}
+	
+	/**
+	 * Returns the highest patch-level that is available for the given mod. If no patches were
+	 * registerd for the mod, this will return 0
+	 *
+	 * @param modID The ID of the mod you want to query
+	 * @return The highest Patch-Level that was found
+	 */
+	public static int maxPatchLevel(@NotNull String modID) {
+		return ALL.stream()
+				  .filter(p -> p.modID
+								.equals(modID))
+				  .mapToInt(p -> p.level)
+				  .max()
+				  .orElse(0);
+	}
+	
+	/**
+	 * Called by inheriting classes.
+	 * <p>
+	 * Performs some sanity checks on the values and might throw a #RuntimeException if any
+	 * inconsistencies are found.
+	 *
+	 * @param modID   The ID of the Mod you want to register a patch for. This should be your
+	 *                ModID only. The ModID can not be {@code null} or an empty String.
+	 * @param version The mod-version that introduces the patch. This needs Semantic-Version String
+	 *                like x.x.x. Developers are responsible for registering their patches in the correct
+	 *                order (with increasing versions). You are not allowed to register a new
+	 *                Patch with a version lower or equal than
+	 *                {@link Patch#maxPatchVersion(String)}
+	 */
+	protected Patch(@NotNull String modID, String version) {
+		//Patchlevels need to be unique and registered in ascending order
+		if (modID == null || "".equals(modID)) {
+			throw new RuntimeException("[INTERNAL ERROR] Patches need a valid modID!");
+		}
+		
+		if (version == null || "".equals(version)) {
+			throw new RuntimeException("Invalid Mod-Version");
+		}
+		
+		this.version = version;
+		this.level = DataFixerAPI.getModVersion(version);
+		if (!ALL.stream()
+				.filter(p -> p.modID
+							  .equals(modID))
+				.noneMatch(p -> p.level >= this.level) || this.level <= 0) {
+			throw new RuntimeException("[INTERNAL ERROR] Patch-levels need to be created in ascending order beginning with 1.");
+		}
+		
+		this.modID = modID;
+	}
+	
+	@Override
+	public String toString() {
+		return "Patch{" + modID + ':' +version + ':' + level + '}';
+	}
+	
+	
+	/**
+	 * Return block data fixes. Fixes will be applied on world load if current patch-level for
+	 * the linked mod is lower than the {@link #level}.
+	 * <p>
+	 * The default implementation of this method returns an empty map.
+	 *
+	 * @return The returned Map should contain the replacements. All occurences of the
+	 * {@code KeySet} are replaced with the associated value.
+	 */
+	public Map<String, String> getIDReplacements() {
+		return new HashMap<String, String>();
+	}
+	
+	/**
+	 * Generates ready to use data for all currently registered patches. The list of
+	 * patches is selected by the current patch-level of the world.
+	 * <p>
+	 * A {@link #Patch} with a given {@link #level} is only included if the patch-level of the
+	 * world is less
+	 * @param config The current patch-level configuration
+	 * @return a new {@link MigrationProfile} Object.
+	 */
+	static MigrationProfile createMigrationData(CompoundTag config) {
+		return new MigrationProfile(config);
+	}
+	
+}
diff --git a/src/main/java/ru/bclib/config/SessionConfig.java b/src/main/java/ru/bclib/config/SessionConfig.java
index 3c311417..8ceff397 100644
--- a/src/main/java/ru/bclib/config/SessionConfig.java
+++ b/src/main/java/ru/bclib/config/SessionConfig.java
@@ -18,8 +18,8 @@ public class SessionConfig extends PathConfig {
 	public final File levelFolder;
 	
 	public SessionConfig(String modID, String group, LevelStorageSource.LevelStorageAccess session, ServerLevel world) {
-		super(modID, group, new File(getWorldFolder(session, world), BCLib.MOD_ID));
+		super(modID, group, new File(getWorldFolder(session, world), BCLib.MOD_ID+"-config"));
 		
-		this.levelFolder = new File(getWorldFolder(session, world), BCLib.MOD_ID);
+		this.levelFolder = new File(getWorldFolder(session, world), BCLib.MOD_ID+"-config");
 	}
 }
diff --git a/src/main/java/ru/bclib/mixin/common/ServerLevelMixin.java b/src/main/java/ru/bclib/mixin/common/ServerLevelMixin.java
index eaf365c0..58aec99b 100644
--- a/src/main/java/ru/bclib/mixin/common/ServerLevelMixin.java
+++ b/src/main/java/ru/bclib/mixin/common/ServerLevelMixin.java
@@ -16,11 +16,9 @@ import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
-import ru.bclib.BCLib;
 import ru.bclib.api.BiomeAPI;
-import ru.bclib.api.DataFixerAPI2;
 import ru.bclib.api.WorldDataAPI;
-import ru.bclib.config.SessionConfig;
+import ru.bclib.api.datafixer.DataFixerAPI;
 
 import java.io.File;
 import java.util.List;
@@ -51,8 +49,7 @@ public abstract class ServerLevelMixin extends Level {
 			dir = dir.getParentFile();
 		}
 		
-		//DataFixerAPI.fixData(dir);
-		DataFixerAPI2.fixData(new SessionConfig(BCLib.MOD_ID, "patches", session, world));
 		WorldDataAPI.load(new File(dir, "data"));
+		DataFixerAPI.fixData(dir);
 	}
 }