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Bun vs Node.js vs Deno (2026): Best JavaScript Runtime?

The JavaScript runtime you pick affects install speed, testing, and production performance. Node.js has ruled for 15 years, but Bun and Deno are challenging with fresh approaches. Here's the honest comparison for 2026.

Quick Comparison

Bun Node.js Deno

Engine JavaScriptCore (Safari) V8 (Chrome)

Language JS + Zig (internals) C++

TypeScript Native (no config) Via ts-node/tsx

Package manager bun install (fastest) npm, yarn, pnpm

Module system CJS + ESM CJS + ESM

Testing Built-in (Jest-compatible) Third-party (Vitest, Jest)

Web APIs Partial Partial

npm compat 90%+ 100% (the original)

Single binary Yes (bun build) Yes (node --compile)

Ecosystem Growing (npm compat helps) Largest (3M+ packages)

Bun — The Speed Demon

Bun is designed for speed above all else.…