Bun 2.0 vs. Node 24 vs. Deno 2.5: The 2026 Runtime Wars

Node is still the standard, but Bun has won the hearts of the Vibe Coders.

In 2024, Bun was “experimental.” In 2026, it’s the default for new startups. But Node.js hasn’t stood still.

The State of Play

Bun 2.0: The Speed Demon

Bun is no longer just a runtime; it’s a “JavaScript Cloud OS.”

  • v2.0 Update: Introduced “Bun Deploy,” a single command that pushes your code to the edge globally.
  • Why use it? 0ms cold starts for serverless functions.
  • Why avoid it? Some obscure legacy C++ gyp bindings still break.

Node 24: The Reliable Giant

Node finally grew up.

  • Native TypeScript: Node 24 finally runs .ts files without a build step (experimental flag removed).
  • .env Support: Native environment variable loading is now standard.
  • Why use it? Enterprise support. If you are a bank, you use Node.

Deno 2.5: The Secure Choice

Deno has pivoted to focus on “Enterprise Security.”

  • JSR: The JavaScript Registry (JSR) has largely replaced npm for modern packages.
  • Why use it? If you need strict permissions (no file access, no net access) by default.

Benchmarks (2026)

BenchmarkBun 2.0Node 24Deno 2.5
HTTP Requests/sec250k80k120k
Startup Time5ms150ms40ms
WebSocket Scale1M conn200k conn600k conn

The “Vercel Effect”

Why did Bun win the startup market? Because Next.js 16 uses a custom “Bun-lite” runtime for its development server. It makes npm run dev start in 0.1 seconds. Once you get used to that speed, you can’t go back to Node.

Recommendation

  • New Project? Use Bun.
  • Legacy Project? Stick to Node.
  • Building a secure internal tool script? Use Deno.