diff --git a/src/registry/r2.ts b/src/registry/r2.ts
index ef09b01..63e2f01 100644
--- a/src/registry/r2.ts
+++ b/src/registry/r2.ts
@@ -11,7 +11,7 @@ import {
 } from "../chunk";
 import { InternalError, ManifestError, RangeError, ServerError } from "../errors";
 import { SHA256_PREFIX_LEN, getSHA256, hexToDigest } from "../user";
-import { readableToBlob, readerToBlob, wrap } from "../utils";
+import { errorString, readableToBlob, readerToBlob, wrap } from "../utils";
 import { BlobUnknownError, ManifestUnknownError } from "../v2-errors";
 import {
   CheckLayerResponse,
@@ -689,13 +689,61 @@ export class R2Registry implements Registry {
     } else {
       const upload = this.env.REGISTRY.resumeMultipartUpload(uuid, state.uploadId);
       // TODO: Handle one last buffer here
-      await upload.complete(state.parts);
-      const obj = await this.env.REGISTRY.get(uuid);
-      const put = this.env.REGISTRY.put(`${namespace}/blobs/${expectedSha}`, obj!.body, {
-        sha256: (expectedSha as string).slice(SHA256_PREFIX_LEN),
-      });
+      const [, errComplete] = await wrap(upload.complete(state.parts));
+      if (errComplete !== null) {
+        console.error("Error completing upload:", errorString(errComplete));
+        return { response: new InternalError() };
+      }
+
+      const [obj, errGetObject] = await wrap(this.env.REGISTRY.get(uuid));
+      if (errGetObject !== null) {
+        console.error("getting object", errorString(errGetObject));
+        return { response: new InternalError() };
+      }
+
+      const blobPath = `${namespace}/blobs/${expectedSha}`;
+
+      const hash = (expectedSha as string).slice(SHA256_PREFIX_LEN);
+      const limitBytes = 1024 * 1024;
+      if (!obj) throw new Error("unreachable");
+
+      if (obj!.size >= limitBytes) {
+        const stream = new crypto.DigestStream("SHA-256");
+        const upload = await this.env.REGISTRY.createMultipartUpload(blobPath);
+        console.warn("Uploading a layer more than", limitBytes, "bytes, consider reducing layer size");
+        const parts = [];
+        for (let i = 0, key = 0; i < obj.size; i += limitBytes, key++) {
+          console.log("uploading", limitBytes, obj.size);
+          const [stream, s2] = limit(obj.body, Math.min(limitBytes, obj.size - i)).tee();
+
+          s2.pipeTo(stream.getWriter(), { preventClose: i + limitBytes < obj.size });
+          parts.push(await upload.uploadPart(key + 1, stream));
+        }
+
+        console.log("digesttt");
+        const digest = await stream.digest;
+        console.log("uploaded", digest);
+        const hexString = [...new Uint8Array(digest)].map((b) => b.toString(16).padStart(2, "0")).join("");
+        if ("sha256:" + hexString != hash) {
+          return {
+            //fixme
+            response: new Response("bad " + hexString, { status: 400 }),
+          };
+        }
+
+        await upload.complete(parts);
+      } else {
+        const put = this.env.REGISTRY.put(blobPath, obj!.body, {
+          sha256: hash,
+        });
+
+        const [, err] = await wrap(put);
+        if (err !== null) {
+          console.error("Error copying blob", errorString(err));
+          return { response: new InternalError() };
+        }
+      }
 
-      await put;
       await this.env.REGISTRY.delete(uuid);
     }
 
diff --git a/src/router.ts b/src/router.ts
index 0a92340..3566540 100644
--- a/src/router.ts
+++ b/src/router.ts
@@ -450,6 +450,7 @@ v2Router.put("/:name+/blobs/uploads/:uuid", async (req, env: Env) => {
   );
 
   if (err) {
+    console.error("Error uploading", err);
     return new InternalError();
   }
 
diff --git a/src/utils.ts b/src/utils.ts
index 2b3e198..c13c338 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -60,7 +60,7 @@ export function errorString(err: unknown): string {
   return "unknown error: " + JSON.stringify(err);
 }
 
-export async function wrap<T, E = unknown>(fn: Promise<T>): Promise<[T, null] | [null, E]> {
+export async function wrap<T, E = Error>(fn: Promise<T>): Promise<[T, null] | [null, E]> {
   return fn.then((data) => [data, null] as [T, null]).catch((err) => [null, err as unknown as E] as [null, E]);
 }