Getting started

1. Install the adapter for your framework (it pulls in @singhak/nodeui-core):

npm install --save-dev @singhak/nodeui-express   # or -fastify / -nestjs / -koa / -hapi / -hono / -http

Installing as a dev dependency is fine: the console is off when NODE_ENV=production, so guard the import if you prune dev dependencies in production images (see step 2).

2. Mount it once, before your routes.

// Express
import { nodeui } from '@singhak/nodeui-express';
const { middleware, server } = nodeui();
app.use(middleware); // must come before your routes so requests are recorded
app.listen(3000, '127.0.0.1', () => server.mark('listening'));

// Fastify (register before your routes so they appear in the Routes panel)
import { nodeui } from '@singhak/nodeui-fastify';
await app.register(nodeui());

// NestJS
@Module({ imports: [NodeUIModule.register()] })
export class AppModule {}

If the package is a dev dependency only, load it conditionally:

if (process.env.NODE_ENV !== 'production') {
  const { nodeui } = await import('@singhak/nodeui-express');
  app.use(nodeui().middleware);
}

3. Start your app in development and open the console:

http://127.0.0.1:<your-port>/nodeui

Use 127.0.0.1 or localhost; other hostnames are rejected unless you add them to allowedHosts. CPU, memory and event-loop sampling starts when you open the console and sleeps after a minute idle. Outgoing calls, queries and logs are captured from startup (see capture), so you can open the console after a problem and still see what led to it.

4. Make it more useful (all optional):

I want to...	Do this
See DB / Redis status in Health	healthChecks: { db: () => pool.query('select 1') }
Add my own panel (queues, flags, cache stats)	plugins: [{ id: 'queues', get: async () => ({ ok: true, data: ... }) }]
Mark startup phases	server.mark('db-connected') → shows in the Startup panel
See app config in the Environment panel	config: { port: 3000, feature: 'x' } (secrets are masked)
Use it from Docker	allowedRemoteAddresses: ['172.16.0.0/12'] and publish 127.0.0.1:3000:3000
Protect it with a token	authToken: '...' then open /nodeui/?token=... once
See Nest logger output	app.useLogger(app.get(NodeUILogger))
Turn it off locally	NODEUI_ENABLED=false

5. Take a heap snapshot (leak hunting): open Heap Snapshot, click the button, confirm. The file is written owner-only and its path is shown; load it in Chrome DevTools → Memory. It contains every secret in memory, so delete it afterwards.

Not working? Check the FAQ below, and look at the startup log: NodeUI prints a warning whenever it is inactive-by-config or exposed more widely than loopback.