diff --git a/common/src/lib/java/dev/engine_room/flywheel/lib/model/baked/MeshHelper.java b/common/src/lib/java/dev/engine_room/flywheel/lib/model/baked/MeshHelper.java
index e6326600b..332fa079b 100644
--- a/common/src/lib/java/dev/engine_room/flywheel/lib/model/baked/MeshHelper.java
+++ b/common/src/lib/java/dev/engine_room/flywheel/lib/model/baked/MeshHelper.java
@@ -2,6 +2,8 @@
 
 import java.nio.ByteBuffer;
 
+import com.mojang.blaze3d.vertex.MeshData;
+
 import org.jetbrains.annotations.Nullable;
 import org.lwjgl.system.MemoryUtil;
 
@@ -16,8 +18,8 @@ final class MeshHelper {
 	private MeshHelper() {
 	}
 
-	public static SimpleMesh blockVerticesToMesh(BufferBuilder.RenderedBuffer buffer, @Nullable String meshDescriptor) {
-		BufferBuilder.DrawState drawState = buffer.drawState();
+	public static SimpleMesh blockVerticesToMesh(MeshData buffer, @Nullable String meshDescriptor) {
+		MeshData.DrawState drawState = buffer.drawState();
 		int vertexCount = drawState.vertexCount();
 		long srcStride = drawState.format().getVertexSize();
 
diff --git a/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/BakedModelBufferer.java b/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/BakedModelBufferer.java
index 2f8a09ca6..62667ab17 100644
--- a/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/BakedModelBufferer.java
+++ b/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/BakedModelBufferer.java
@@ -2,9 +2,10 @@
 
 import java.util.Iterator;
 
+import com.mojang.blaze3d.vertex.MeshData;
+
 import org.jetbrains.annotations.Nullable;
 
-import com.mojang.blaze3d.vertex.BufferBuilder.RenderedBuffer;
 import com.mojang.blaze3d.vertex.PoseStack;
 
 import it.unimi.dsi.fastutil.objects.Reference2ReferenceMap;
@@ -129,7 +130,7 @@ public static void bufferMultiBlock(BlockRenderDispatcher renderDispatcher, Iter
 	}
 
 	public interface ResultConsumer {
-		void accept(RenderType renderType, boolean shaded, RenderedBuffer data);
+		void accept(RenderType renderType, boolean shaded, MeshData data);
 	}
 
 	private static class ThreadLocalObjects {
diff --git a/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/MeshEmitter.java b/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/MeshEmitter.java
index 268a6e1da..801f8b261 100644
--- a/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/MeshEmitter.java
+++ b/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/MeshEmitter.java
@@ -1,5 +1,10 @@
 package dev.engine_room.flywheel.lib.model.baked;
 
+import com.mojang.blaze3d.vertex.ByteBufferBuilder;
+import com.mojang.blaze3d.vertex.MeshData;
+
+import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
+
 import org.jetbrains.annotations.UnknownNullability;
 
 import com.mojang.blaze3d.vertex.BufferBuilder;
@@ -8,16 +13,20 @@
 
 import net.minecraft.client.renderer.RenderType;
 
+import java.util.Map;
+
 class MeshEmitter {
 	private final RenderType renderType;
-	private final BufferBuilder bufferBuilder;
+	private final ByteBufferBuilder buffer;
+	private BufferBuilder bufferBuilder;
 
 	private BakedModelBufferer.@UnknownNullability ResultConsumer resultConsumer;
 	private boolean currentShade;
 
 	MeshEmitter(RenderType renderType) {
 		this.renderType = renderType;
-		this.bufferBuilder = new BufferBuilder(renderType.bufferSize());
+		this.buffer = new ByteBufferBuilder(renderType.bufferSize());
+		this.bufferBuilder = new BufferBuilder(buffer, VertexFormat.Mode.QUADS, DefaultVertexFormat.BLOCK);
 	}
 
 	public void prepare(BakedModelBufferer.ResultConsumer resultConsumer) {
@@ -25,9 +34,7 @@ public void prepare(BakedModelBufferer.ResultConsumer resultConsumer) {
 	}
 
 	public void end() {
-		if (bufferBuilder.building()) {
-			emit();
-		}
+		emit();
 		resultConsumer = null;
 	}
 
@@ -37,22 +44,22 @@ public BufferBuilder getBuffer(boolean shade) {
 	}
 
 	void prepareForGeometry(boolean shade) {
-		if (!bufferBuilder.building()) {
-			bufferBuilder.begin(VertexFormat.Mode.QUADS, DefaultVertexFormat.BLOCK);
-		} else if (shade != currentShade) {
+		bufferBuilder = new BufferBuilder(buffer, VertexFormat.Mode.QUADS, DefaultVertexFormat.BLOCK);
+
+		if (shade != currentShade) {
 			emit();
-			bufferBuilder.begin(VertexFormat.Mode.QUADS, DefaultVertexFormat.BLOCK);
+			bufferBuilder = new BufferBuilder(buffer, VertexFormat.Mode.QUADS, DefaultVertexFormat.BLOCK);
 		}
 
 		currentShade = shade;
 	}
 
 	void emit() {
-		var renderedBuffer = bufferBuilder.endOrDiscardIfEmpty();
+		MeshData meshData = bufferBuilder.build();
 
-		if (renderedBuffer != null) {
-			resultConsumer.accept(renderType, currentShade, renderedBuffer);
-			renderedBuffer.release();
+		if (meshData != null) {
+			resultConsumer.accept(renderType, currentShade, meshData);
+			meshData.close();
 		}
 	}
 }
diff --git a/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/PartialModelEventHandler.java b/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/PartialModelEventHandler.java
index 21f802f07..7a6b6514a 100644
--- a/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/PartialModelEventHandler.java
+++ b/fabric/src/lib/java/dev/engine_room/flywheel/lib/model/baked/PartialModelEventHandler.java
@@ -2,6 +2,8 @@
 
 import java.util.List;
 
+import net.minecraft.client.resources.model.ModelResourceLocation;
+
 import org.jetbrains.annotations.ApiStatus;
 
 import dev.engine_room.flywheel.api.Flywheel;
@@ -24,7 +26,7 @@ public static ResourceLocation[] onRegisterAdditional() {
 
 	public static void onBakingCompleted(ModelManager manager) {
 		for (PartialModel partial : PartialModel.ALL) {
-			partial.set(manager.getModel(partial.getLocation()));
+			partial.set(manager.getModel(ModelResourceLocation.inventory(partial.getLocation())));
 		}
 	}
 
diff --git a/fabric/src/main/java/dev/engine_room/flywheel/impl/FlywheelFabric.java b/fabric/src/main/java/dev/engine_room/flywheel/impl/FlywheelFabric.java
index 67354150d..756d37abe 100644
--- a/fabric/src/main/java/dev/engine_room/flywheel/impl/FlywheelFabric.java
+++ b/fabric/src/main/java/dev/engine_room/flywheel/impl/FlywheelFabric.java
@@ -73,9 +73,10 @@ private static void setupLib() {
 		EndClientResourceReloadCallback.EVENT.register((minecraft, resourceManager, initialReload, error) ->
 				ModelHolder.onEndClientResourceReload());
 
-		ModelLoadingPlugin.register(ctx -> {
-			ctx.addModels(PartialModelEventHandler.onRegisterAdditional());
-		});
+		//fixme 1.21 porting
+//		ModelLoadingPlugin.register(ctx -> {
+//			ctx.addModels(PartialModelEventHandler.onRegisterAdditional());
+//		});
 		ResourceManagerHelper.get(PackType.CLIENT_RESOURCES).registerReloadListener(PartialModelEventHandler.ReloadListener.INSTANCE);
 	}