Monitoring Setup - Observability Configuration

Overview

Sets up the "detect before users complain" system. Minimum viable monitoring that grows with your startup.

1. When to Apply

2. Monitoring Stack by Budget

3. Essential Alerts (Day 1)

## Must-Have Alerts

| Alert | Condition | Channel | Priority |
|-------|-----------|---------|----------|
| **Site Down** | Health check fails 3x | Slack + PagerDuty | P0 |
| **Error Rate Spike** | >5% 5xx in 5 min | Slack | P1 |
| **Slow Response** | p95 > 2s for 5 min | Slack | P2 |
| **DB Connections** | >80% pool used | Slack | P1 |
| **Disk Space** | >85% used | Slack | P2 |
| **Memory** | >90% for 10 min | Slack | P1 |
| **SSL Expiry** | <14 days to expiry | Email | P2 |

4. Quick Setup: Sentry (Error Tracking)

// Next.js — sentry.client.config.ts
import * as Sentry from "@sentry/nextjs"

Sentry.init({
  dsn: process.env.NEXT_PUBLIC_SENTRY_DSN,
  tracesSampleRate: 0.1,      // 10% of transactions
  replaysSessionSampleRate: 0, // Save cost, enable when needed
  environment: process.env.NODE_ENV,
})

# FastAPI — main.py
import sentry_sdk
from sentry_sdk.integrations.fastapi import FastApiIntegration

sentry_sdk.init(
    dsn=os.getenv("SENTRY_DSN"),
    traces_sample_rate=0.1,
    environment=os.getenv("ENVIRONMENT", "production"),
    integrations=[FastApiIntegration()],
)

5. Health Check Endpoint

// app/api/health/route.ts
export async function GET() {
  const checks = {
    status: 'ok',
    timestamp: new Date().toISOString(),
    uptime: process.uptime(),
    checks: {
      database: await checkDB(),
      redis: await checkRedis(),
    }
  }
  const allHealthy = Object.values(checks.checks).every(c => c === 'ok')
  return Response.json(checks, { status: allHealthy ? 200 : 503 })
}

6. Tool Coordination

7. Boundaries

Will:

• Generate monitoring configurations for major platforms
• Set up error tracking (Sentry), uptime monitoring, basic APM
• Define alert thresholds appropriate for startups
• Create health check endpoints

Will Not:

• Create cloud provider accounts
• Set up PagerDuty/OpsGenie on-call rotations
• Build custom dashboards (recommend tools instead)
• Monitor business metrics (use metrics-tracker)