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TypeScript 7 native API adds emit methods

Published: July 24, 2026

The native TypeScript codebase has added programmatic emit APIs for tools that need to generate JavaScript or declaration output.

What changed

The merged API provides four emit paths with different output and selection behavior.

  • program.emit(emitOnly?: EmitOnly) emits the whole program to the file system, including a configured virtual file system, and respects emit-blocking options such as noEmit and noEmitOnError.
  • program.emitToString(emitOnly?: EmitOnly) emits the whole program to in-memory string results and also respects emit-blocking options.
  • program.getJavaScriptEmit(files?: readonly DocumentIdentifier[]) returns in-memory JavaScript output for selected files and bypasses emit-blocking options.
  • program.getDeclarationEmit(files?: readonly DocumentIdentifier[]) provides the corresponding selected-file declaration output.

This gives API consumers separate choices for normal whole-program emit and targeted in-memory output.

Availability

The change was merged into the native TypeScript codebase on July 24, 2026. The source does not identify a stable npm version containing these APIs, so tools should verify support in the TypeScript version they use.

Source

Read the official pull request: API emit.