Your SaaS Will Break — Here's How to See It Coming

Most SaaS founders deploy without basic observability. Then something breaks—usually at 2 AM—and they scramble through logs trying to figure out what happened.

I've been there. Multiple times. Across half a dozen products. And I've learned this: systems fail naturally. You don't need traffic spikes or malicious actors. Just time.

The difference between a recoverable incident and a catastrophic one isn't how fast you code—it's how quickly you can see what's wrong. That requires leaving breadcrumbs before things go sideways.

You Don't Need Complexity. You Need Visibility.

Forget Prometheus, Grafana, and distributed tracing. Those are for teams managing thousands of services. If you're running solo, you need four things:

1. Error Logging to Stdout

Every application error should print to standard output. Not buried in files. Not swallowed by try-catch blocks. Visible, immediately.

Most deployment platforms (Railway, Fly.io, Render) capture stdout automatically. If an error happens, you see it. No configuration. No setup. Just awareness.

// Simple error logging middleware
app.use((err, req, res, next) => {
  console.error('Error:', {
    message: err.message,
    stack: err.stack,
    path: req.path,
    method: req.method,
    timestamp: new Date().toISOString()
  });
  res.status(500).json({ error: 'Internal server error' });
});

2. Sentry Integration

You'll miss errors. Not because you're careless—because edge cases exist that you didn't anticipate. Sentry catches unhandled exceptions you'd never see otherwise.

Set it up once. Forget about it. When something breaks, you'll get an email with context: what user did what, which browser, what data triggered the failure. It's like having QA watching production 24/7.

// Sentry setup (Node.js example)
const Sentry = require('@sentry/node');

Sentry.init({
  dsn: process.env.SENTRY_DSN,
  environment: process.env.NODE_ENV,
  tracesSampleRate: 0.1, // 10% of requests traced
});

// Use as Express middleware
app.use(Sentry.Handlers.requestHandler());
app.use(Sentry.Handlers.errorHandler());

3. Health Check Endpoint

Create a /healthz or /health endpoint that returns 200 if your app is alive and can reach critical dependencies (database, cache, external APIs).

Point an uptime monitor at it (UptimeRobot, BetterStack, or your deployment platform's built-in monitor). If it fails, you get alerted before users notice.

// Basic health check
app.get('/healthz', async (req, res) => {
  try {
    // Check database connection
    await db.query('SELECT 1');

    // Check cache if you use one
    await cache.ping();

    res.status(200).json({
      status: 'healthy',
      timestamp: new Date().toISOString()
    });
  } catch (error) {
    console.error('Health check failed:', error);
    res.status(503).json({
      status: 'unhealthy',
      error: error.message
    });
  }
});

4. Request Latency Capture

Add simple middleware that logs request duration. You don't need percentiles or histograms—just awareness of which endpoints are slow.

When users complain about performance, you'll know exactly which route to investigate instead of guessing.

// Request timing middleware
app.use((req, res, next) => {
  const start = Date.now();

  res.on('finish', () => {
    const duration = Date.now() - start;
    if (duration > 1000) { // Log slow requests (>1s)
      console.warn('Slow request:', {
        method: req.method,
        path: req.path,
        duration: `${duration}ms`,
        status: res.statusCode
      });
    }
  });

  next();
});

This Isn't About Perfection. It's About Survival.

You're not Google. You don't need five-nines uptime or sub-100ms response times. You need to know when things break and have enough context to fix them quickly.

These four practices give you that. They're not sophisticated, but they're sufficient. And when you're running solo, sufficient beats sophisticated every time.

The Insurance You'll Actually Use

I've looked back at logs from products I launched years ago. Those breadcrumbs—timestamps, error messages, request paths—made the difference between debugging in minutes versus hours.

Observability isn't a luxury for enterprises. It's basic hygiene for anyone building software that matters. Set it up once, and you'll thank yourself every time something breaks.

Because it will break. The question is whether you'll see it coming.