Enable TypeScript Batch Mode

If you're using @nx/js:tsc to build your projects, you can opt in to its batch implementation. It uses the TypeScript APIs for incremental builds to batch task execution into a single process, which is faster than the default one-process-per-task approach. The larger the task graph, the bigger the speedup.

Experimental feature

Executing tasks in batch mode is an experimental feature.

Requirements

Building a project with the @nx/js:tsc executor in batch mode requires all dependent projects (excluding implicit dependencies) to be buildable and built using the @nx/js:tsc executor.

To run your builds using the batch implementation, pass in --batch flag:

nx build my-project --batch

For optimal performance, you could set the clean option to false. Otherwise, the executor cleans the output folder before running the build, which results in the loss of the .tsbuildinfo file and, consequently, the loss of important optimizations performed by TypeScript. This is not a requirement. Even if the clean option is not set to false there are other important optimizations that are performed by the batch implementation.

// libs/ts-lib/project.json
{
  "build": {
    "executor": "@nx/js:tsc",
    "options": {
      "outputPath": "dist/libs/ts-lib",
      "main": "libs/ts-lib/src/index.ts",
      "tsConfig": "libs/ts-lib/tsconfig.lib.json",
      "assets": ["libs/ts-lib/*.md"],
      "clean": false
    }
  }
}

You can get a sense of the performance improvements over using the @nx/js:tsc default implementation in the tsc batch mode benchmark.