Getting started

Quick start

Install the peekinside package, attach it to your app, and open the dashboard.

Install#

npm install peekinside

PeekInside needs Node.js 18 or later.

Attach it to your app#

import express from 'express';
import PeekInside from 'peekinside';

const app = express();
PeekInside.attach(app);

app.use(express.json());
// ...your routes

app.listen(3000);

Start your app as usual. PeekInside prints the link to its dashboard:

[peekinside] Requests from orders-api: http://localhost:7335/p/orders-api-1a2b3c4d

Middleware order doesn't matter: request bodies are captured as your app reads them.

Koa, Fastify and native http#

PeekInside.attach(koaApp);        // new Koa()
PeekInside.attach(fastify);       // Fastify(), before fastify.listen()
PeekInside.attach(server);        // http.createServer(...)

Servers created with http.createServer(app) are detected automatically.

TypeScript and CommonJS#

Type definitions ship with the package:

import PeekInside, { type PeekInsideOptions } from 'peekinside';

const options: PeekInsideOptions = { project: 'orders-api', ignorePaths: ['/health', /^\/metrics/] };
PeekInside.attach(app, options);

They use the Node.js types from @types/node, which TypeScript projects for Node.js already have.

PeekInside is an ES module. CommonJS apps load it with require() on Node.js 20.19+ and 22.12+:

const { default: PeekInside } = require('peekinside');

TypeScript compiled to CommonJS can keep import PeekInside from 'peekinside', with esModuleInterop (on by default with "module": "nodenext").

Next#