This release features 8 months of work: changes from 244 different contributors, spread among 1183 commits.
Perhaps most notably, this release debuts I/O as an Interface, but don't sleep on the Language Changes or enhancements to the Compiler, Build System, Linker, Fuzzer, and Toolchain which are also included in this release.

What we did need, however, was a Git server implementation that could run on Cloudflare Workers. It needed to be small, as complete as possible, extensible (notes, LFS), and efficient. So we built one in Zig, and compiled it to Wasm.

Why did we use Zig? Three reasons:

1. The entire git protocol engine is written in pure Zig (no libc), compiled to a ~100KB WASM binary (with room for optimization!). It implements SHA-1, zlib inflate/deflate, delta encoding/decoding, pack parsing, and the full git smart HTTP protocol — all from scratch, with zero external dependencies other than the standard library.

2. Zig gives us manual control over memory allocation which is important in constrained environments like Durable Objects. The Zig Build System lets us easily share code between the WASM runtime (production) and native builds (testing against libgit2 for correctness verification).

3. The WASM module communicates with the JS host via a thin callback interface: 11 host-imported functions for storage operations (host_get_object, host_put_object, etc.) and one for streaming output (host_emit_bytes). The WASM side is fully testable in isolation.

Under the hood, Artifacts also uses R2 (for snapshots) and KV (for tracking auth tokens):

I'm planning to do a stream in an hour or two from now

After a long, unplanned hiatus, I'll do a live coding stream starting in a couple hours from now.
Main topic will be a demo of some partially completed changes to the build system, and pushing forward on it a little bit.
Q&A will also be welcome from chat.

https://www.

twitch.tv/andrewrok/

In Bun’s zig fork, we added parallel semantic analysis and multiple codegen units to the llvm backend on macOS & Linux

This makes debug builds of Bun compile > 4x faster, improving internal development velocity

We do not currently plan to upstream this, as Zig has a strict ban on LLM-authored contributions.

kristoff_it 4 days ago
Bun has stopped donating to the ZSF after the Anthropic acquisition

the binary size shrinks by 3 MB - 8 MB, the benchmarks are between neutral and faster