Incremental Compilation

incremental compilation stores metadata about a previous successful build, allowing later runs to reuse some analysis. It can speed up large projects but does not change the meaning of types. Treat .tsbuildinfo as build state; configure a suitable location and avoid relying on it as source content.

The program produces the same JavaScript behavior whether TypeScript compiles from a fresh cache or reuses incremental build information. The tsbuildinfo file controls analysis reuse only.

incremental:true does not mean every rebuild takes constant time; dependency changes may invalidate substantial work.

Save as incremental-compilation.ts. The following program passed strict TypeScript compilation, and the displayed output was captured by executing its emitted JavaScript with Node.js 22.16.0.

TypeScript source

const tasks = ["compile", "check", "run"];
console.log(tasks.join(" -> "));

Verified output

compile -> check -> run

Compile: npx tsc --strict --target es2022 --module commonjs incremental-compilation.ts; run: node incremental-compilation.js. For Node.js API examples, install @types/node first. For browser projects, use the browser-specific instructions below.

The example demonstrates the code-level behavior; the related configuration or test commands are shown separately when needed.

The program produces the same JavaScript behavior whether TypeScript compiles from a fresh cache or reuses incremental build information. The tsbuildinfo file controls analysis reuse only.

Predict what changes if you alter one input. Then run the code to compare your reasoning with the real output.

Practical project lab: These are real configuration and source-file examples, not a TypeScript object that merely describes settings. Place the files at the named paths relative to one project directory.

tsconfig.json

{"compilerOptions":{"target":"ES2022","module":"CommonJS","strict":true,"incremental":true,"tsBuildInfoFile":"./.cache/build.tsbuildinfo"}}

main.ts

console.log("incremental");

Commands

mkdir -p .cache
npx tsc -p .
npx tsc -p .

The second build can reuse metadata; compare the output regardless of caching.

This local compiler or test-runner mini-project was validated in addition to the primary program.

incremental:true does not mean every rebuild takes constant time; dependency changes may invalidate substantial work.

Identify whether the failure is a type-checking issue, a configuration issue, or a runtime behavior issue before choosing a fix.

Enable incremental:true, build twice, and observe creation and reuse of the .tsbuildinfo file.

Write down your expected result first. For configuration examples, compare compiler output and diagnostics; for test examples, make the assertion fail deliberately to verify that the tool reports it.

For the exact current options and platform behavior, consult the official documentation. These examples were verified using the tool versions described above.

incremental compilation stores metadata about a previous successful build, allowing later runs to reuse some analysis.

Run the primary example, then complete the practice task or environment-specific lab.