@simplesteps/local

Local execution runtime for SimpleSteps. Compile TypeScript workflows to ASL with @simplesteps/core, then run and test them locally with mock services — no AWS account needed.

Install

npm install @simplesteps/local

Usage

import { compile } from '@simplesteps/core';
import { LocalRunner } from '@simplesteps/local';

// Compile your workflow
const result = compile({ sourceFiles: ['workflow.ts'] });
const asl = result.stateMachines[0].asl;

// Execute locally with mock services
const runner = new LocalRunner(asl, {
  services: {
    'arn:aws:lambda:us-east-1:123456789:function:MyFn': async (input) => {
      return { status: 'ok' };
    },
  },
});

const output = await runner.execute({ orderId: '123' });
console.log(output);

Execution Traces

Use executeWithTrace to inspect the full state-by-state execution path:

const { output, trace } = await runner.executeWithTrace({ orderId: '123' });

for (const entry of trace.states) {
  console.log(`${entry.name} (${entry.type})`);
}

Features

• Supports all 8 ASL state types (Task, Pass, Choice, Wait, Succeed, Fail, Parallel, Map)
• Both JSONata and JSONPath query languages
• All 18 States.* intrinsic functions
• Choice state comparison operators and compound rules
• Full data flow pipeline (InputPath, Parameters, ResultSelector, ResultPath, OutputPath)
• Error handling (Catch/Retry)
• Execution tracing for test assertions

Documentation

• Getting Started
• Language Reference

Playground | GitHub

License

MIT