Node.js to Bun Migration

Migrate an existing Node.js project to Bun 1.4+. This involves analyzing dependencies, updating configurations, and leveraging Bun's native APIs to replace npm packages.

What's new in Bun 1.4

Bun 1.4 dramatically expands what you can drop in from npm — and what you can delete entirely:

• Playwright runs on Bun via connectOverCDP() and playwright test
• vitest runs under Bun with --coverage, threads, and forks pools
• Next.js 16 works with bun --bun next build and Turbopack
• OpenTelemetry http/fs instrumentation works with node:http and node:fs
• dd-trace and @datadog/pprof work via V8 C++ API implementations
• Node.js 26.3.0 compatibility: +1,517 newly passing tests
• 3× faster bun:ffi for native bindings

Migration Workflow

1. Pre-Migration Analysis