Bun is joining Anthropic
Bun has been acquired by Anthropic. Anthropic is betting on Bun as the infrastructure powering Claude Code, Claude Agent SDK, and future AI coding products & tools.
Publisher
Bun
Stories with reporting from Bun: the top stories first, then everything newest first. Each story links to the original articles.
Top stories
Bun 1.4
Bun 1.4 rewrites Bun in Rust, ships built-in headless browser automation (Bun.WebView), Bun.Image, Bun.markdown, JSON5, JSONL, Terminal and cron APIs, Node.js 26.3.0 compatibility with 1,517 newly passing tests, parallel test and run, Windows ARM64, and an opt-in global virtual…
Latest
Bun v1.4.2
This release fixes two regressions impacting Elysia and AsyncLocalStorage, a hang in @discordjs/ws, CMYK JPEG decoding in Bun.Image, a rare JIT crash, and a GC crash on musl.
Bun v1.4.1
Fixes 202 issues, addressing 236 👍. HTTP/2 in Bun.serve, Bun.write() streams Response bodies to disk, self-contained workspace node_modules, bun install --offline and --prefer-offline, WebSocket pause() and resume(), crypto.argon2, tree-shaking through dynamic import(), smarter…
Rewriting Bun in Rust
Bun v1.3.14
Fixes 92 issues (addressing 380 👍). Bun.Image — a built-in image processing API, 7x faster warm installs with the isolated linker's global store, experimental HTTP/2 and HTTP/3 clients for fetch(), HTTP/3 (QUIC) in Bun.serve(), rewritten fs.watch() on Linux and macOS…
Bun v1.3.13
Fixes 82 issues (addressing 381 👍). bun test --parallel, --isolate, --shard, and --changed, bun install streams tarballs to disk using 17x less memory, source maps use 8x less memory, 5.5x faster gzip with zlib-ng, Range request support in Bun.serve(), SHA3 in node:crypto and…
Bun v1.3.12
Fixes 120 issues (addressing 219 👍). Render Markdown in the terminal with bun ./file.md, Bun.WebView headless browser automation, in-process Bun.cron() scheduler, async stack traces for native errors, 2.3x faster URLPattern, 2x faster Bun.Glob.scan, cgroup-aware parallelism on…
Bun v1.3.11
Fixes 105 issues (addressing 307 👍). 4 MB smaller on Linux. x64 Bun.cron for OS-level cron jobs and expression parsing, Bun.sliceAnsi for ANSI/grapheme-aware string slicing, richer Bun.markdown list metadata; bun test --path-ignore-patterns; native Windows ARM64 .bin shim; dgram…
Bun v1.3.10
Fixes 155 issues (addressing 642 👍). New native REPL, --compile --target=browser for self-contained HTML, TC39 standard ES decorators, Windows ARM64 support, barrel import optimization, and a faster event loop. structuredClone up to 25x faster for arrays, Buffer.slice() 1.8x…
Bun v1.3.9
Fixes 23 issues (addressing 13 👍). Run multiple scripts in --parallel or --sequential. bun:test mock & spyOn get Symbol.dispose support. ESM bytecode compilation. Faster Bun.markdown. Faster RegExp, String.prototype.trim, String.prototype.startsWith.
Bun v1.3.8
Fixes 8 issues (addressing 6 👍). Bun.markdown is a builtin CommonMark-compliant Markdown parser written in Zig. Bun's bundler gets bun build --metafile-md to write LLM-friendly module graph metadata. Fixes a regression in 'npm install -g bun' on Windows.
Bun v1.3.7
Fixes 91 issues (addressing 243 👍). 50% faster Buffer.from(array), 35% faster async/await, 3x faster array.flat(), 90% faster padStart/padEnd via JSC upgrade. New: Bun.JSON5, Bun.JSONL, Bun.wrapAnsi() (33-88x faster than wrap-ansi npm), --heap-prof-md, --cpu-prof-md…
Bun v1.3.6
Fixes 45 issues (addressing 125 👍). Bun.Archive API for creating & extracting tarballs with gzip compression, Bun.JSONC for parsing JSON with comments, metafile & files options in Bun.build for bundle analysis and virtual files, Response.json() 3.5x faster, 15% faster…
Bun v1.3.5
Fixes 32 issues (addressing 25 👍). Bun.Terminal API, compile-time feature flags, improved Bun.stringWidth accuracy, V8 C++ value type checking APIs, Content-Disposition support for S3 uploads, environment variable expansion in .npmrc quoted values, and numerous bug fixes &…
Bun v1.3.4
Fixes 194 issues (addressing 412 👍). URLPattern API, Fake Timers for bun:test, Custom Proxy Headers in fetch(),console.log %j format, http.Agent connection pooling fix, Standalone executable config loading changes, SQLite 3.51.1, and numerous bugfixes for bun:test, Node.js…
Bun v1.3.3
Fixes 95 issues (addressing 348 👍). CompressionStream and DecompressionStream, Control .env and bunfig.toml loading in standalone executables, retry and repeats in bun:test, --no-env-file, SQLite 3.51.0, Upgraded to Zig 0.15.2, Bugfixes for bundler, bun install, Windows, Node.js…
Bun v1.3.2
Fixes 287 issues (addressing 324 👍). Hoisted installs restored as default for backward compatibility. CPU profiling with --cpu-prof, faster installs for packages with post-install scripts, bun:test onTestFinished hook, ServerWebSocket subscriptions getter, Alpine 3.22 in Docker…
Vercel now supports the Bun Runtime
Deploy and run your applications with Bun's fast JavaScript runtime on Vercel Functions, with full access to Bun APIs and improved performance
Bun v1.3.1
Fixes 103 issues (addressing 172 👍). 2× faster bun build on macOS for symlink-heavy projects, source maps preserve legal comments, and --format=cjs now inlines import.meta; bun test adds global vi, --pass-with-no-tests, and --only-failures; .npmrc :email auth support, faster…