@c3-oss/doppel-core - Embeddable terminal and schedule engine

@c3-oss/doppel-core is the transport-agnostic engine behind Doppel. It manages named PTY sessions, ephemeral command runs, cron-backed schedules, and local persistence without starting the published daemon server.

Use it when your application wants Doppel's terminal automation model as a library.

Install

npm install @c3-oss/doppel-core

Requires Node.js 22+.

Quickstart

import { createDoppel } from '@c3-oss/doppel-core';

const doppel = createDoppel();

const session = doppel.terminal.ensure({ name: 'dev' });
doppel.terminal.send(session.name, 'pnpm test\n');

const result = await doppel.terminal.runEphemeral('printf doppel');
console.log(result.output);

doppel.close();

API shape

const doppel = createDoppel({
  dataDir: './.doppel',
});

doppel.terminal.ensure({ name: 'dev' });
doppel.terminal.send('dev', 'echo hi\n');
await doppel.terminal.runEphemeral('echo once');

doppel.schedules.create({
  name: 'daily-health',
  cron: '0 9 * * *',
  command: 'pnpm test',
  enabled: true,
});

doppel.close();

The engine exposes:

• terminal for named PTY sessions, input, output history, and ephemeral runs.
• schedules for cron-backed scheduled commands.
• close() for shutting down terminal and persistence resources.

Related packages

• @c3-oss/doppel-server wraps this engine with Fastify, tRPC, WebSocket, and daemon commands.
• @c3-oss/doppel is the CLI client for a running Doppel server.

Links

• Repository: https://github.com/c3-oss/doppel
• CLI package: https://www.npmjs.com/package/@c3-oss/doppel
• Server package: https://www.npmjs.com/package/@c3-oss/doppel-server