TypeScript 6.0 trims the fat and speeds up builds

TypeScript keeps growing because it turns chaotic JavaScript into a system that scales. The next big leap is TypeScript Native. Microsoft is porting the toolchain to a native implementation that targets faster builds, lower memory use, and snappier editor feedback. Previews are available, and you can get speed wins right now even before the native port is production ready.

References:

• Announcements: A 10x Faster TypeScript and TypeScript Native Previews
• Current stable versions: TypeScript on npm
• Earlier improvements: Announcing TypeScript 5.6

Why This Matters

• Build speed affects every commit and review cycle
• Editor responsiveness drives flow and reduces context switching
• Lower memory helps large monorepos and CI runners
• Better incremental compiles remove the need for hacks in complex workspaces

What TypeScript Native Is

TypeScript today is primarily implemented in TypeScript and runs on Node. The Native project reimplements key parts in a lower level language, packaged for easy use. The goals are:

• Faster cold and warm compiles
• Lower RAM and better cache behavior
• Drop in usage via a thin wrapper so you keep your tsconfig and setup

Read the official posts for design goals and current status: Native port overview and Preview builds.

What Changes For You Right Now

• The stable compiler on npm remains typescript@5.x for production CI
• You can experiment locally with the native preview on a branch
• Most projects can compare compile times without changing code or configs

Try The Native Preview Locally

# Install the preview tooling in a throwaway branch
npm i -D @typescript/native-preview

# Typecheck a project with the native preview
npx tsnp tsc -p tsconfig.json

# Compare against current tsc
time npx tsnp tsc -p tsconfig.json
time npx tsc -p tsconfig.json

Tips for fair benchmarks

• Run each command twice and compare the second run for warm cache behavior
• Clear node_modules/.cache or your build cache if you rely on tooling caches
• Measure both typecheck only and emit workflows if you compile JS

Practical Speedups You Can Ship Today

Even without the native port, you can make builds faster and more reliable.

1) Project References plus Incremental

Break large repos into referenced projects so TypeScript can reuse artifacts.

{
  "compilerOptions": {
    "composite": true,
    "incremental": true,
    "tsBuildInfoFile": "./.tsbuildinfo"
  },
  "references": [{ "path": "../core" }, { "path": "../web" }]
}

Build graph first, then dependents:

npx tsc -b packages/core packages/web

2) Limit The Graph

• Keep node_modules out of the program where possible
• Avoid deep wildcard path aliases that drag in large trees
• Prefer explicit references over wildcard includes

3) Typecheck Where It Matters

If your bundler already handles emit, split typecheck from build. For example in a monorepo CI:

# Step 1: fast build for artifacts
pnpm -r --filter ./packages/* run build:emit

# Step 2: centralized typecheck
pnpm -r --filter ./packages/* run typecheck

4) Use --noCheck only where safe

Recent TS releases added options that skip checking in certain emit paths. Use them only for leaf apps where type errors are still caught elsewhere.

5) Speed Up Tests

For projects heavy on tests, keep transforms minimal and prefer ts-node or precompiled JS for test runners depending on your stack.

Editor Responsiveness

The native project aims to cut latency when you type and navigate. You can usually boost editor performance today by:

• Turning on project references so the language service loads fewer files
• Ensuring exclude removes generated files and large folders
• Keeping a single workspace open in your editor instead of many nested ones

Migration Playbook

1. Stabilize configs: ensure each package builds cleanly with tsc -b
2. Benchmark baseline: record current cold and warm times for typecheck and emit
3. Try native preview locally on one package and record results
4. Roll out to a staging branch if numbers look good
5. Keep CI on stable typescript until the native toolchain is production ready

FAQ

Is TypeScript Native a drop in replacement?
Goal is yes for common workflows. Follow the preview notes for any flags that differ and keep an eye on plugin compatibility.

Will it speed up every project?
Most will benefit, especially large repos and slow CI runners. Measure your own project because module resolution, transforms, and bundlers can dominate cost.

What about build systems like Turborepo, Nx, or Bazel?
They still help since they cache work across tasks. A faster compiler makes caches warm sooner and misses less painful.

Final Thoughts

TypeScript Native is the right bet for long term velocity. You can try it today, measure real numbers, and still keep production builds on stable TypeScript. Combine the preview with references, saner graphs, and a clean CI split, and your team gets faster feedback with fewer flakey steps.

Further Reading

• Native project overview: 10x Faster TypeScript
• Preview builds and usage: TypeScript Native Previews
• Current stable versions: TypeScript on npm
• Recent compiler improvements: TypeScript 5.6