#runtime

The JavaScript runtime, bundler, and toolkit built by a 14-person team and relied on by millions of developers has been acquired by Anthropic. Bun will remain open source and MIT-licensed, but the roadmap now bends toward AI coding infrastructure.

Bun's latest release adds WebView for headless browser automation, lands TC39's using/await using in JavaScriptCore, and delivers a 2.3x speedup to URLPattern.

QuickBEAM is a JavaScript runtime that runs inside the BEAM VM — the same virtual machine powering Erlang and Elixir. It integrates JavaScript into OTP supervision trees, lets JS call Elixir functions and OTP libraries, and ships with a built-in TypeScript toolchain.

Deno 2.7 is a substantial mid-cycle release: the Temporal API is now production-ready, native Windows on ARM builds land, npm overrides work like in Node, and dozens of Node.js compatibility improvements land across worker_threads, child_process, zlib, and sqlite.

Bun v1.3.11 drops a 4MB smaller binary, ships Bun.cron for OS-level scheduled jobs, and marks a pivotal moment as the runtime joins Anthropic to power Claude Code and future AI coding tools.

Three JavaScript runtimes. Three different philosophies. Independent benchmarks across HTTP throughput, cold starts, and async performance tell a clearer story than marketing ever could. Here's the brutally honest breakdown for developers choosing their next server-side JS platform.