@huggingface/blake3-jit

Temporary fork of blake3-jit by @Brooooooklyn with performance enhancements for Hugging Face Xet content-defined chunking.

This package will be deprecated once upstream blake3-jit exposes these changes.

Changes from upstream

1. Hasher.reset() method — resets the hasher to process a new message with the same key/flags, reusing all internal buffers (zero allocations per hash).

2. Pre-allocated internal buffers — parentBlock, parentCv, chunkCv, outWords, and finalizeCv are allocated once in the constructor and reused across update/finalize calls, significantly reducing GC pressure in hot loops.

3. ChunkState.resetTo() method — allows reusing ChunkState instances instead of allocating new ones per chunk.

4. Removed Uint32Array view fast-path in ChunkState.update — the byte-by-byte readLittleEndianWordsFull path was empirically faster and avoids RangeError on unaligned offsets.

5. Dual ESM/CJS output via tshy — the upstream package is ESM-only; this fork uses tshy to produce both ESM and CommonJS builds, required for compatibility with Node.js CJS consumers.

These changes are also available as a patch file at packages/xetchunk-wasm/patches/blake3-jit.patch (applicable to the upstream dist bundle).

Installation

npm install @huggingface/blake3-jit

Usage

import { hash, Hasher } from "@huggingface/blake3-jit";

// One-shot hashing
const digest = hash(new Uint8Array([1, 2, 3]));

// Incremental hashing with reset (zero-alloc reuse)
const hasher = new Hasher();
hasher.update(chunk1);
const hash1 = hasher.finalize();

hasher.reset();
hasher.update(chunk2);
const hash2 = hasher.finalize();

// Keyed hashing (MAC)
const mac = Hasher.newKeyed(key).update(message).finalize();

Upstream

This is a fork of blake3-jit — a high-performance BLAKE3 implementation with runtime JIT WASM SIMD, created by LongYinan (@Brooooooklyn).

See the upstream repository for full documentation, benchmarks, and architecture details.

License

MIT — see LICENSE