Bun is a fast all-in-one JavaScript runtime, bundler, test runner, and package manager built on JavaScriptCore. The Taycan team is evaluating it as an alternative to Node.js for specific internal tooling and build scripts where startup time and install speed matter most.

Initial benchmarks on our monorepo tooling show promising results: bun install completes in ~2s vs ~12s for npm install, and script startup is 3-4x faster. However, we have encountered compatibility issues with some Node.js APIs our services depend on — particularly around node:cluster and certain native addon patterns.

Bun is not yet being considered for production services. The assessment focuses on developer tooling and CI scripts where its speed advantages are most impactful and compatibility risks are lowest.