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NodeRuntime

Node.js process runner for Effect programs.

This module exports runMain, which runs one Effect as the main process fiber in Node.js. It reuses the shared Node runtime runner, including its error reporting, SIGINT / SIGTERM interruption, and optional teardown behavior.

1 exports Added in v4.0.0 Source

Running

runMain

Added in v4.0.0 Source

Helps you run a main effect with built-in error handling, logging, and signal management.

When to use

Use to run a Node.js application's main Effect with structured error handling, log management, interrupt support, or advanced teardown capabilities.

Details

This function launches an Effect as the main entry point, setting exit codes based on success or failure, handling interrupts (e.g., Ctrl+C), and optionally logging errors. By default, it logs errors and uses a "pretty" format, but both behaviors can be turned off. You can also provide custom teardown logic to finalize resources or produce different exit codes.

The optional configuration object can include: - disableErrorReporting: Turn off automatic error logging. - teardown: Provide custom finalization logic.

Signature

declare const runMain: {
  (options?: {
    readonly disableErrorReporting?: boolean;
    readonly teardown?: Runtime.Teardown;
  }): <E, A>(effect: Effect<A, E>) => void;
  <E, A>(
    effect: Effect<A, E>,
    options?: {
      readonly disableErrorReporting?: boolean;
      readonly teardown?: Runtime.Teardown;
    },
  ): void;
};