EvoReplay for Node.js (evoreplay-node)

The Reference Implementation of the EvoReplay Deterministic Execution SDK.

Installation

npm install evoreplay-node

Quick Start

1. Initialize

Add this as early as possible in your application entry point (e.g., index.js or app.js).

const { EvoReplay } = require('evoreplay-node');

EvoReplay.init({
    mode: 'production',
    privacy: 'strict'
});

2. Manual Capture (Optional)

While EvoReplay automatically captures Date.now(), Math.random(), and external I/O, you can manually wrap critical logic.

// Capture a boolean decision for the replay graph
const isFeatured = EvoReplay.captureDecision('feature_flag_check', () => {
    return checkFeatureFlag('new-ui');
});

CLI Usage (Replay)

You can replay artifacts generated by this SDK using the evoreplay command inside the artifact.

# If you have the global CLI or Go CLI installed
evoreplay replay crash_123.evor

API Reference

EvoReplay.init(config)

• config.mode: 'production' (default) or 'debug'
• config.privacy: 'strict' (hashes inputs) or 'relaxed'

EvoReplay.startRecording(contextId)

Manually start a trace for a specific request ID.

EvoReplay.stopRecording()

Returns the artifact (string/buffer) and halts recording.

License

MIT