Oven has released Bun 1.2, continuing to close compatibility gaps with Node.js while pushing runtime performance forward.
Express 4 and 5 Fully Compatible
Bun's Node compatibility layer now passes the complete Express.js test suite for both v4 and v5. Production apps built on Express, including those using popular middleware like Helmet, Passport, and Multer, typically run without changes — often 30-50% faster due to the Zig-based HTTP server underneath.
SQLite WASM Fallback
For environments where the native SQLite binary can't be loaded (some serverless platforms, FIPS-compliant systems), Bun now ships a WASM-compiled SQLite that's drop-in compatible with bun:sqlite. Performance overhead is 15-25% but functionality is identical.
Windows Performance
File-system operations on Windows are 2-3x faster thanks to native NTFS APIs replacing the POSIX compatibility shim. bun install on a typical Next.js project drops from 12s to under 5s.
