Application Performance Monitoring

Every millisecond tells a story.

Add one middleware to your API. Get latency percentiles, error tracking, throughput analytics, and smart alerting — all in a beautiful dark interface.

middleware.ts

app.use(async (req, res, next) => {
  const start = Date.now();
  res.on("finish", () => {
    fetch("https://heartbeater.pro/api/ingest", {
      method: "POST",
      headers: { "x-api-key": "sk_live_..." },
      body: JSON.stringify({
        method: req.method,
        path: req.route?.path,
        status_code: res.statusCode,
        duration_ms: Date.now() - start,
      }),
    });
  });
  next();
});

Telemetry Streaming

p95: 42ms

Error Rate: 0.2%

How It Works

Three steps to full visibility.

Register Your Service

Create a service and get your API key. Takes 30 seconds.

Add the Middleware

Drop in our one-line middleware for Express, Fastify, Flask, or any HTTP framework.

Watch the Data Flow

See latency, errors, and throughput populate in real-time on your dashboard.

Features

Built for production.

Latency Percentiles

Track p50, p95, p99 for every endpoint in real-time.

Deep Analytics

14-day throughput trends, error rate breakdowns, and traffic charts.

Error Tracking

Auto-group errors by message, see affected endpoints and stack traces.

Smart Alerting

Get notified on latency spikes, error rate surges, and throughput drops.

Enterprise Security

API key auth, RLS-protected data, encrypted at rest.

Dark Interface

Purpose-built dark UI designed for production incident response.

Pricing Plans

Simple, transparent pricing.

Starter

$0/ forever

Start monitoring your API with essential performance insights.

1 Service
5 Tracked Endpoints
7-Day Data Retention
Basic Slack Alerts
Community Support

PRO RECOMMENDED

Business

$24/ seat

For teams that need deeper analytics, longer retention and high-volume limits.

10 Services
100 Tracked Endpoints
30-Day Data Retention
Multi-Channel Alerts
Priority Email Support
Error Grouping & Traces

app.use(async (req, res, next) => { const start = Date.now(); res.on("finish", () => { fetch("https://heartbeater.pro/api/ingest", { method: "POST", headers: { "x-api-key": "sk_live_..." }, body: JSON.stringify({ method: req.method, path: req.route?.path, status_code: res.statusCode, duration_ms: Date.now() - start, }), }); }); next(); });