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Bun

DEVOPS
Velocity5.0

Fast all-in-one JavaScript runtime and toolkit

bun.sh ↗

Bun rewrote its entire runtime from Zig to Rust and shipped HTTP/2 server support in v1.4.

javascript-runtimenodejs-compatibilityrusthttp2performance
◆Current state
Bun made two foundational moves in 2026: a complete Zig-to-Rust rewrite announced in July, and a v1.4.1 release that ships HTTP/2 server support in Bun.serve, workspace-scoped node_modules, argon2 in crypto, tree-shaking through dynamic imports, and a 9x throughput gain on Buffer I/O. The runtime now handles most production server workloads that previously required Node.js.
◆Where it's heading
Bun is methodically closing Node.js compatibility gaps while building APIs Node.js does not have — Bun.Image, Bun.cron, Bun.WebView, HTTP/2+3 support. The Rust rewrite signals long-term commitment to safety and contributor ecosystem depth that Zig could not provide. At this pace, a v2.0 major is the next logical milestone to formalize the built-in API surface.
◆Prediction
A 2.0 major release will likely stabilize the HTTP/2 and HTTP/3 server story and formalize the Bun.Image and Bun.cron APIs as supported. The Rust migration should produce measurably lower crash rates in subsequent releases.

◆Recent moves

  1. 11d ago

    Bun v1.4.2

    v1.4.2 patches two regressions from v1.4.1 — an Elysia/AsyncLocalStorage interaction and a Discord.js hang — plus a JPEG decoding fix. Expected cleanup after a large feature drop.

    View source ↗
  2. 12d ago

    Bun v1.4.1

    v1.4.1 is the most feature-dense Bun release since 1.0: HTTP/2 in Bun.serve, workspace node_modules isolation, argon2, 9x faster Buffer I/O, and 2x faster AsyncLocalStorage together close the remaining gaps preventing Bun from replacing Node.js in production server workloads.

    View source ↗
  3. 2mo ago

    Bun rewrites its runtime from Zig to Rust

    ⚡ SPARK

    Bun's full rewrite from Zig to Rust is the most consequential architectural decision since the project's founding — it reshapes the runtime's safety profile, contributor ceiling, and long-term credibility as production infrastructure.

    View source ↗
  4. 4mo ago

    Bun v1.3.14

    v1.3.14 introduced Bun.Image as a built-in image processing API, 7x faster warm package installs via an isolated linker global store, and experimental HTTP/2 and HTTP/3 client support — the point where Bun started broadening from a runtime into a batteries-included platform.

    View source ↗
  5. 4mo ago

    Bun v1.3.13

    v1.3.13 added parallel, isolated, and sharded test execution — directly addressing the gap keeping teams on Jest or Vitest even when bundling with Bun. Streaming tarball installs cutting memory use 17x also matters for CI environments with constrained resources.

    View source ↗
  6. 5mo ago

    Bun v1.3.12

    v1.3.12 shipped Bun.WebView for headless browser automation and Bun.cron() for in-process cron scheduling — native APIs collapsing what would normally require separate dependencies. This release pushed Bun toward replacing the full Node.js toolchain, not just the runtime.

    View source ↗