Inngest CLI

Inngest CLI

Master the Inngest CLI for local development, testing, and self-hosted production. The CLI provides the Dev Server — a fully-featured, open-source local version of the Inngest Platform.

These skills are focused on TypeScript. For Python or Go, refer to the Inngest documentation for language-specific guidance. Core concepts apply across all languages.

Use this skill for CLI setup, Dev Server workflows, local testing, Docker, MCP, and self-hosted server operations. For run/trace inspection through inngest api, use inngest-api-cli when available.

Installation

# npx (recommended — always latest)
npx inngest-cli@latest dev

# yarn
yarn dlx inngest-cli@latest dev

# pnpm
pnpm dlx inngest-cli@latest dev

# Global install
npm install -g inngest-cli

# Docker
docker pull inngest/inngest

If your npm configuration disables lifecycle scripts and the binary is missing, retry with npx --ignore-scripts=false inngest-cli@latest dev. Bun does not support lifecycle scripts by default, so prefer npx for the CLI even in Bun projects.

inngest dev — Local Dev Server

Starts an in-memory local version of Inngest with a browser UI at http://localhost:8288.

# Auto-discover apps on common ports/endpoints
npx inngest-cli@latest dev

# Specify your app URL
npx inngest-cli@latest dev -u http://localhost:3000/api/inngest

# Custom port
npx inngest-cli@latest dev -p 9999

# Multiple apps
npx inngest-cli@latest dev \
  -u http://localhost:3000/api/inngest \
  -u http://localhost:4000/api/inngest

# Disable auto-discovery (use with -u)
npx inngest-cli@latest dev --no-discovery -u http://localhost:3000/api/inngest

CLI Flags

Auto-Discovery

Without --no-discovery, the Dev Server scans common ports and endpoints automatically:

Ports scanned: Common development ports including 3000, 3030, and others

Endpoints scanned:

• /api/inngest
• /x/inngest
• /.netlify/functions/inngest
• /.redwood/functions/inngest

Configuration File

Create an inngest.json (or .yaml, .toml) in your project root. The CLI walks up directories to find it.

{
  "sdk-url": [
    "http://localhost:3000/api/inngest",
    "http://localhost:3030/api/inngest"
  ],
  "no-discovery": true
}

# inngest.yaml
sdk-url:
  - "http://localhost:3000/api/inngest"
  - "http://localhost:3030/api/inngest"
no-discovery: true

Environment Variables

Debugging Your Serve Endpoint

Verify your serve() endpoint is configured correctly:

curl -s http://localhost:3000/api/inngest | jq

{
  "message": "Inngest endpoint configured correctly.",
  "hasEventKey": false,
  "hasSigningKey": false,
  "functionsFound": 3
}

If functionsFound is 0, check that your functions are passed to the serve() call.

Testing Functions Locally

Send Events via SDK

import { Inngest } from "inngest";

const inngest = new Inngest({ id: "my-app" });

await inngest.send({
  name: "user/signup.completed",
  data: {
    userId: "user_123",
    email: "user@example.com",
  },
});

Send Events via curl

curl -X POST "http://localhost:8288/e/test" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "user/signup.completed",
    "data": {
      "userId": "user_123",
      "email": "user@example.com"
    }
  }'

The event key in the URL path (test above) can be any value locally.

Unit Testing with @inngest/test

Requires inngest@>=4.0.0.

npm install -D @inngest/test

import { InngestTestEngine } from "@inngest/test";
import { helloWorld } from "./functions";

// Execute full function
const t = new InngestTestEngine({ function: helloWorld });
const { result } = await t.execute();
expect(result).toEqual("Hello World!");

// Test a single step
const { result: stepResult } = await t.executeStep("calculate-price");
expect(stepResult).toEqual(123);

// Assert step state
const { state } = await t.execute();
await expect(state["my-step"]).resolves.toEqual("output");
await expect(state["risky-step"]).rejects.toThrowError("failed");

// Mock events
const { result: eventResult } = await t.execute({
  events: [{ name: "demo/event.sent", data: { message: "Hi!" } }],
});

// Mock step responses
const { result: mockResult } = await t.execute({
  steps: [{ id: "external-api-call", handler() { return { status: "ok" }; } }],
});

// Mock sleep/waitForEvent (pause-inducing steps require mocking)
await t.execute({
  steps: [{ id: "wait-one-day", handler() {} }],
});

Mock external dependencies with your test framework's standard mocking (jest.mock, vi.mock, etc.) — @inngest/test handles only Inngest-specific mocking.

Docker Setup

Standalone

docker run -p 8288:8288 -p 8289:8289 \
  inngest/inngest \
  inngest dev -u http://host.docker.internal:3000/api/inngest

Use host.docker.internal to reach your app running on the host machine (works out of the box on Docker Desktop). On Linux, add --add-host=host.docker.internal:host-gateway or use an equivalent host-access method.

Docker Compose

services:
  app:
    build: ./app
    environment:
      - INNGEST_DEV=1
      - INNGEST_BASE_URL=http://inngest:8288
    ports:
      - "3000:3000"
  inngest:
    image: inngest/inngest
    command: "inngest dev -u http://app:3000/api/inngest"
    ports:
      - "8288:8288"
      - "8289:8289"

Port 8288 is the main server and UI. Port 8289 is the connect() WebSocket gateway.

Critical: Set INNGEST_DEV=1 on your app — the TypeScript SDK defaults to Cloud mode, which will skip the Dev Server.

MCP Server (AI Dev Tools)

The Dev Server exposes an MCP server at http://127.0.0.1:8288/mcp (HTTP transport).

# Claude Code
claude mcp add --transport http inngest-dev http://127.0.0.1:8288/mcp