Bun 1.2 vs Node.js 22: Which Runtime Should You Pick in 2026?

The State of JavaScript Runtimes in 2026

Two years ago, choosing a JavaScript runtime meant choosing Node.js. Today you have three serious options: Node.js 22, Bun 1.2, and Deno 2. This guide focuses on the two most common choices for new backend projects in 2026: Bun 1.2 and Node.js 22.

What Bun 1.2 Adds

Bun 1.2 is a major compatibility and productivity release:

• Native S3 and R2 API - Bun.s3 and Bun.r2 for object storage without the AWS SDK
• 90% Node.js API compatibility - virtually all npm packages work now
• Hot module reloading - bun --hot for server-side hot reload
• Node.js test runner compatibility - node:test module supported
• Windows stability - first fully stable Windows release

// Native S3 in Bun 1.2  -  no AWS SDK needed
const file = Bun.s3.file("uploads/photo.png");
await file.write(imageBuffer, { type: "image/png" });
const url = file.presign({ expiresIn: 3600 });

Performance Benchmarks

These numbers are from independent benchmarks on identical hardware (M2 Pro, 16GB RAM):

*Node.js 22 now includes a built-in SQLite module (node:sqlite), though Bun's is faster.

bun --hot vs nodemon

Bun's native hot reload is faster and does not require a separate package:

# Bun  -  built in
bun --hot server.ts

# Node.js  -  requires nodemon or tsx --watch
npx nodemon --exec ts-node server.ts

With --hot, Bun reloads only the changed module and its dependents, preserving open connections. This is closer to Vite HMR than a full process restart.

Node.js 22: What's New

Node.js 22 is not standing still:

// Built-in SQLite  -  no better-sqlite3 needed
import { DatabaseSync } from "node:sqlite";

const db = new DatabaseSync(":memory:");
db.exec("CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)");
const insert = db.prepare("INSERT INTO users (name) VALUES (?)");
insert.run("Alice");

require(esm) is now stable - you can require() ES modules from CommonJS code without async imports. This unblocks a long-standing ecosystem problem.

Node.js 22 also gets permission model improvements (experimental --experimental-permission) and a native test runner that has matured significantly.

When to Pick Bun

• New API services where performance matters
• Scripts and CLI tools (startup time is critical)
• Projects that need native S3/R2 without the AWS SDK
• Teams comfortable on the bleeding edge

When to Pick Node.js

• Existing codebases with complex webpack/PostCSS build pipelines
• Projects requiring 100% ecosystem compatibility (rare edge cases still hit Bun)
• Enterprise environments with Node.js as the supported runtime
• When deploying to platforms that only support Node.js officially

Install and Try

# Install Bun
curl -fsSL https://bun.sh/install | bash

# Run a Node.js project with Bun (usually zero config)
bun install
bun run start

References: Bun 1.2 · Node.js 22