Getting Started

This page gets you from zero to a first strict check in about two minutes.

Prerequisites

• Node.js ≥ 18 (for the npm launcher).

• A project with a tsconfig.json.

• A native TypeScript compiler. Either:

  • TypeScript 7 or later — the typescript package now ships the native compiler (recommended), or
  • @typescript/native-preview — for teams whose app stays on TypeScript 5/6. It installs the native compiler for strict checking without changing the typescript your app builds with.

  Or set TSGO_BINARY to point at an existing tsc/tsgo binary.

Install

npm

npm install --save-dev @coralogix/tsgo-strict typescript@^7

pnpm

pnpm add -D @coralogix/tsgo-strict typescript@^7

yarn

yarn add -D @coralogix/tsgo-strict typescript@^7

typescript is declared as an optional peer dependency — tsgo-strict only needs a native compiler, which can come from typescript@7+, @typescript/native-preview, a binary on PATH, or the TSGO_BINARY env var.

Not ready to move your app to TypeScript 7?

You don't have to. Keep your app on its current typescript and add the native compiler just for strict checking:

npm install --save-dev @coralogix/tsgo-strict @typescript/native-preview

tsgo-strict prefers an installed @typescript/native-preview over your app's typescript, so your build is unaffected.

On install, npm will pick up exactly one of the @coralogix/tsgo-strict-<platform> subpackages (via optionalDependencies) and use its prebuilt native binary. No compile step runs on your machine.

Configure a strict subset

Add the plugin block to your tsconfig.json:

{
  "compilerOptions": {
    "plugins": [
      {
        "name": "typescript-strict-plugin",
        "paths": ["./src/strict", "./src/shared"],
        "excludePattern": ["**/*.test.ts"]
      }
    ]
  }
}

• paths — directory prefixes included in the strict subset. A file is included if its path lives under any entry. Omit for "include everything" and rely on pragmas / excludePattern to scope down.
• excludePattern — array of minimatch glob patterns (a single string is also accepted). Files matching any pattern are excluded.

See Configuration for the full reference.

Run it

npx tsgo-strict

Output looks like tsc:

src/strict/foo.ts(12,5): error TS2345: Argument of type '...' is not assignable to parameter of type '...'.

Found 1 error in 1 file.

Exit codes:

Code	Meaning
0	No strict diagnostics.
1	Strict diagnostics found.
2	Tool, config, or runtime error.

Add it to CI

Run it as a separate step in your pipeline. Because it only reports strict diagnostics, you can gate PRs on strict compliance for the opted-in subset while letting the rest of the build run on your normal tsc:

- name: Typecheck (normal)
  run: npx tsc --noEmit

- name: Typecheck (strict subset)
  run: npx tsgo-strict

See Incremental migration for recommended rollout patterns.

What's next?

• Pragmas — override the config on a per-file basis.
• How it works — the 5-step pipeline.
• CLI reference — every flag and env var.
• Programmatic API — run it from Node.