You've built your MVP. Your code works. Tests pass. You're ready to launch, right?

Not quite.

68% of startup launches experience a critical issue in the first 48 hours. Most of these issues are preventable with a simple pre-launch checklist.

This isn't about achieving perfection. It's about avoiding the embarrassing, business-killing mistakes that sink launches before they even start.

In this guide, I'll walk you through the 10 critical tests you must run before launching your MVP - based on analyzing 200+ startup launches and interviewing founders who learned these lessons the hard way.

Why This Checklist Matters

Real story: A SaaS startup launched on Product Hunt without testing their signup flow under load. Within 10 minutes of hitting #1:

Signup API crashed
4,000 visitors couldn't sign up
By the time they fixed it (2 hours later), traffic had died down
They got 200 signups instead of the estimated 2,000+
Lost a $500K funding opportunity because the investors tried to sign up during the outage

Time to create this checklist: 2 hours Cost to fix the issues: $0 Value of prevention: Literally their entire business

Let's make sure this doesn't happen to you.

The 10-Point MVP Launch Checklist

✅ 1. Security Testing

Why it matters: A security breach on day 1 destroys credibility and can be fatal.

What to test:

SQL Injection

// Test these inputs in all forms:
' OR '1'='1
'; DROP TABLE users--
1' UNION SELECT * FROM users--
 
// Your API should:
✅ Reject or escape these inputs
✅ Return generic error messages (don't reveal DB structure)
✅ Log suspicious activity

XSS (Cross-Site Scripting)

<!-- Test these in text inputs: -->
<script>alert('XSS')</script>
<img src=x onerror=alert('XSS')>
 
<!-- Your app should: -->
✅ HTML-escape all user input before displaying
✅ Use Content Security Policy headers
✅ Sanitize data before storing

Authentication & Authorization

# Test scenarios:
1. Can logged-out users access protected endpoints?
2. Can user A access user B's data?
3. Can you access admin endpoints without admin role?
4. Does password reset actually verify email ownership?
5. Are sessions invalidated on logout?

Quick security checklist:

SQL injection protected (use parameterized queries)
XSS protected (escape/sanitize all user input)
CSRF tokens on all state-changing requests
HTTPS enabled (redirect HTTP → HTTPS)
Secure password hashing (bcrypt, min 10 rounds)
Rate limiting on auth endpoints (prevent brute force)
Session timeout configured (30 min recommended)
Security headers set (CSP, X-Frame-Options, etc.)

Tools:

OWASP ZAP - Free security scanner
Snyk - Dependency vulnerability scanner
npm audit - Check for vulnerable packages

✅ 2. Load & Stress Testing

Why it matters: Your app might work with 10 users, but what about 100? Or 1,000?

What to test:

Smoke Test (Health Check)

// Can your API handle minimal load?
- Users: 3-5 concurrent
- Duration: 60 seconds
- Expected: 100% success rate, under 500ms response time

Load Test (Expected Traffic)

// Can you handle your launch day traffic?
- Users: Your expected peak × 1.5
- Duration: 15-30 minutes
- Expected: under 1% errors, under 500ms P95 latency

Stress Test (Breaking Point)

// Where does everything break?
- Users: Increase from 10 → 500+ gradually
- Duration: 10-20 minutes
- Goal: Find your breaking point

Checklist:

Smoke test passes (0% errors at low load)
Load test passes (handles expected peak traffic)
Breaking point identified (you know your limits)
Can handle 3x expected traffic
Database connection pool sized correctly
No memory leaks detected

Calculation example:

Expected launch traffic:
- 5,000 visitors in 24 hours
- Peak hour: 1,500 visitors (30% of daily)
- Concurrent users: 150 (10% of hourly)

Test with: 150 × 1.5 = 225 concurrent users

✅ 3. Error Handling & Recovery

Why it matters: Your app will encounter errors. How it handles them determines user experience.

What to test:

API Errors

// Test scenarios:
1. Invalid input (missing required fields)
2. Malformed JSON
3. Authentication failure
4. Database connection lost
5. External API timeout
6. Rate limit exceeded
 
// Each should return:
✅ Appropriate HTTP status code
✅ User-friendly error message
✅ Don't expose stack traces or internal errors
✅ Log error details for debugging

Example error response:

// BAD ❌
{
  "error": "TypeError: Cannot read property 'id' of undefined at /app/server.js:42"
}
 
// GOOD ✅
{
  "error": "Invalid request",
  "message": "User ID is required",
  "code": "MISSING_USER_ID"
}

Database Failures

// What happens if:
- Database is unreachable?
- Query times out?
- Connection pool exhausted?
 
// Your app should:
✅ Return 503 Service Unavailable
✅ Attempt retry (with exponential backoff)
✅ Fail gracefully (don't crash the entire app)
✅ Alert engineering team

Checklist:

All API endpoints return proper HTTP status codes
Error messages are user-friendly (no stack traces)
Failed database queries don't crash the app
Timeouts configured for external API calls
Retry logic with exponential backoff
Circuit breakers for external dependencies

✅ 4. Monitoring & Alerting

Why it matters: You can't fix what you can't see. Set up monitoring before launch, not after the crash.

What to monitor:

Application Metrics

// Must-have metrics:
- Request rate (requests/second)
- Error rate (% of failed requests)
- Response time (P50, P95, P99)
- Active users
- Database query performance

Infrastructure Metrics

// System health:
- CPU usage (alert if >80%)
- Memory usage (alert if >85%)
- Disk space (alert if >80%)
- Network bandwidth
- Database connections (alert if >80% of pool)

Business Metrics

// Track what matters:
- Signups per hour
- Conversion rate
- Revenue/transactions
- User activation rate

Alert thresholds (set these BEFORE launch):

Critical alerts (wake up at 3am):
- Error rate > 5%
- API response time P95 > 2 seconds
- CPU > 90% for 5 minutes
- Memory > 95%
- Service completely down
 
Warning alerts (check in the morning):
- Error rate > 1%
- Response time P95 > 1 second
- CPU > 70% for 10 minutes
- Disk space < 20%

Tools (pick one of each category):

Error Tracking:

Sentry - Best for error tracking (free tier available)
Rollbar - Alternative
Bugsnag - Alternative

Application Monitoring:

New Relic - Comprehensive APM
Datadog - Popular choice
CloudWatch - If using AWS

Checklist:

Error tracking configured (Sentry, Rollbar, etc.)
Performance monitoring set up (New Relic, Datadog)
Alerts configured for critical thresholds
Log aggregation working (centralized logs)
Uptime monitoring (ping service every 60s)
Team notified when alerts trigger (PagerDuty, Slack)

✅ 5. Database Backups & Recovery

Why it matters: If you lose your database, you lose your business. Period.

What to configure:

Automated Backups

# Daily backups (minimum)
- Frequency: Every 24 hours
- Retention: Keep 30 days
- Storage: Off-site (different region than primary DB)
- Testing: Restore backup monthly to verify it works
 
# Better: Continuous backups
- Point-in-time recovery (restore to any moment)
- Automatic snapshots every hour
- Retained for 7+ days

Backup Testing

# YOU MUST TEST RESTORES BEFORE LAUNCH
 
1. Take a backup of test database
2. Delete the test database
3. Restore from backup
4. Verify all data is intact
5. Time how long restoration takes
 
# If you've never tested a restore, you don't have backups.

Disaster Recovery Plan

# What to do if database is lost:
 
1. Stop all write operations immediately
2. Switch app to read-only mode or maintenance mode
3. Restore from latest backup
4. Verify data integrity
5. Resume operations
6. Post-mortem: What happened? How to prevent?
 
# Document this BEFORE you need it
# Practice restoring at least once

Checklist:

Automated daily backups enabled
Backups stored off-site (different region)
Successfully tested a restore
Know restoration time (under 30 min? 2 hours?)
Backup alerts configured (alert if backup fails)
Team knows disaster recovery process
Consider read replicas for high-traffic apps

✅ 6. Rate Limiting & API Protection

Why it matters: Without rate limiting, a single malicious user or bot can take down your entire API.

What to implement:

Per-IP Rate Limiting

// Express example
const rateLimit = require('express-rate-limit');
 
const limiter = rateLimit({
  windowMs: 15 * 60 * 1000, // 15 minutes
  max: 100, // 100 requests per window per IP
  message: 'Too many requests, please try again later'
});
 
app.use('/api/', limiter);

Per-User Rate Limiting

// Authenticated endpoint limits
const authLimiter = rateLimit({
  windowMs: 60 * 1000, // 1 minute
  max: 60, // 60 requests per minute per user
  keyGenerator: (req) => req.user.id
});
 
app.use('/api/user/', authLimiter);

Stricter Limits for Expensive Operations

// Auth endpoints (prevent brute force)
const authLimit = rateLimit({
  windowMs: 15 * 60 * 1000,
  max: 5, // Only 5 login attempts per 15 minutes
  skipSuccessfulRequests: true
});
 
app.post('/api/login', authLimit, loginHandler);
app.post('/api/signup', authLimit, signupHandler);

Rate limiting strategy by endpoint:

Public endpoints: 100 req/15min per IP
Authenticated endpoints: 60 req/min per user
Auth endpoints: 5 req/15min per IP
Write operations: 30 req/min per user
Expensive queries: 10 req/min per user

Checklist:

Rate limiting enabled on all API endpoints
Stricter limits on auth endpoints (5/15min)
Per-user limits on authenticated endpoints
Proper error responses (429 Too Many Requests)
Rate limit info in response headers
Whitelist for monitoring/health checks

✅ 7. SSL/TLS & HTTPS Configuration

Why it matters: Without HTTPS, passwords and data are sent in plain text. Major security risk and Google penalizes you in search.

What to configure:

SSL Certificate

# Free SSL from Let's Encrypt
certbot --nginx -d yourdomain.com -d www.yourdomain.com
 
# Automatic renewal
certbot renew --dry-run

Force HTTPS

// Redirect all HTTP to HTTPS
app.use((req, res, next) => {
  if (req.header('x-forwarded-proto') !== 'https' && process.env.NODE_ENV === 'production') {
    res.redirect(`https://${req.header('host')}${req.url}`);
  } else {
    next();
  }
});

Security Headers

const helmet = require('helmet');
 
app.use(helmet());  // Sets multiple security headers
 
// Or manually:
app.use((req, res, next) => {
  res.setHeader('Strict-Transport-Security', 'max-age=31536000; includeSubDomains');
  res.setHeader('X-Content-Type-Options', 'nosniff');
  res.setHeader('X-Frame-Options', 'DENY');
  res.setHeader('X-XSS-Protection', '1; mode=block');
  next();
});

Checklist:

SSL certificate installed and valid
HTTP redirects to HTTPS
HSTS header set (Strict-Transport-Security)
Security headers configured (use Helmet.js)
SSL certificate auto-renewal configured
Test with SSL Labs (aim for A+)

✅ 8. Health Check Endpoints

Why it matters: Load balancers and monitoring tools need to know if your app is healthy. Plus, you need a quick way to verify everything is working.

What to implement:

Basic Health Check

// Simple ping endpoint
app.get('/health', (req, res) => {
  res.status(200).json({ status: 'ok', timestamp: Date.now() });
});

Detailed Health Check

// Check all dependencies
app.get('/health/detailed', async (req, res) => {
  const health = {
    status: 'ok',
    checks: {
      database: 'ok',
      redis: 'ok',
      externalAPI: 'ok'
    }
  };
 
  // Check database
  try {
    await db.query('SELECT 1');
  } catch (err) {
    health.checks.database = 'error';
    health.status = 'degraded';
  }
 
  // Check Redis
  try {
    await redis.ping();
  } catch (err) {
    health.checks.redis = 'error';
    health.status = 'degraded';
  }
 
  // Check external API
  try {
    await fetch('https://external-api.com/health', { timeout: 2000 });
  } catch (err) {
    health.checks.externalAPI = 'error';
    health.status = 'degraded';
  }
 
  const statusCode = health.status === 'ok' ? 200 : 503;
  res.status(statusCode).json(health);
});

Readiness vs Liveness

// Liveness: Is the app running?
app.get('/health/live', (req, res) => {
  res.status(200).json({ status: 'alive' });
});
 
// Readiness: Is the app ready to accept traffic?
app.get('/health/ready', async (req, res) => {
  // Check if database is connected, caches are warm, etc.
  const ready = await checkAllDependencies();
  const statusCode = ready ? 200 : 503;
  res.status(statusCode).json({ ready });
});

Checklist:

Basic /health endpoint returns 200
Detailed health check for all dependencies
Readiness endpoint for load balancer
Health check doesn't require authentication
Health check responds within 1 second
Uptime monitoring pings /health every 60s

✅ 9. Environment Configuration

Why it matters: Hardcoded secrets in code = eventual security breach. Separate configs for dev/staging/prod prevents mistakes.

What to configure:

Environment Variables

# .env (NEVER commit to git)
DATABASE_URL=postgresql://user:pass@localhost:5432/mydb
REDIS_URL=redis://localhost:6379
JWT_SECRET=your-super-secret-key-here
STRIPE_SECRET_KEY=sk_live_...
SENDGRID_API_KEY=SG...
 
# Load with:
require('dotenv').config();

.env.example for Team

# .env.example (commit this to git)
DATABASE_URL=
REDIS_URL=
JWT_SECRET=
STRIPE_SECRET_KEY=
SENDGRID_API_KEY=

Different Configs per Environment

// config.js
module.exports = {
  development: {
    database: process.env.DEV_DATABASE_URL,
    logLevel: 'debug',
    rateLimit: false
  },
  production: {
    database: process.env.DATABASE_URL,
    logLevel: 'error',
    rateLimit: true
  }
}[process.env.NODE_ENV || 'development'];

Checklist:

All secrets in environment variables (not hardcoded)
.env file in .gitignore
.env.example committed to repo
Different configs for dev/staging/prod
Team knows how to get production secrets (password manager)
Secrets rotated regularly (quarterly minimum)

✅ 10. Deployment & Rollback Plan

Why it matters: When something goes wrong (and it will), you need to rollback instantly. Not in 30 minutes.

What to prepare:

Deployment Checklist

Before deploying to production:
 
1. [ ] All tests pass (unit, integration, E2E)
2. [ ] Load/stress tests pass
3. [ ] Security scan complete (no critical vulnerabilities)
4. [ ] Database migrations tested on staging
5. [ ] Environment variables updated
6. [ ] Team notified of deployment window
7. [ ] Rollback plan ready
8. [ ] Monitoring dashboard open
9. [ ] Deploy to staging first, verify it works
10. [ ] Schedule deployment during low-traffic time

One-Command Rollback

# You should be able to rollback with ONE command
 
# Example with Git + PM2
git checkout previous-working-commit
npm install
pm2 restart all
 
# Example with Docker
docker-compose down
docker-compose up -d previous-version
 
# Example with Heroku
heroku rollback
 
# Example with Vercel/Netlify
# Use dashboard to rollback to previous deployment

Deployment Process

1. Deploy to staging
2. Run smoke tests on staging
3. If staging tests pass, deploy to production
4. Monitor error rates for 10 minutes
5. If error rate spikes, rollback immediately
6. If all good, announce deployment complete

Checklist:

Staging environment mirrors production
One-command deployment process
One-command rollback process
Zero-downtime deployment (or scheduled maintenance window)
Database migrations are reversible
Team practiced rollback procedure
Deployment logs are saved

Launch Day Checklist

24 hours before launch:

Run full test suite one more time
Verify all monitoring alerts work (trigger test alert)
Ensure team has access to all systems
Set up incident communication channel (Slack channel)
Review rollback procedure with team

1 hour before launch:

Database backup completed successfully
Monitoring dashboards open
Team online and ready
Rate limiting enabled
Health check responding correctly

During launch:

Watch error rate in real-time
Monitor response times
Check database connection pool usage
Watch memory/CPU usage
Be ready to rollback if needed

After launch (first 24 hours):

Check error logs hourly
Monitor signup/conversion rates
Review performance metrics
Respond to user feedback
Document any issues for future prevention

When Things Go Wrong

Decision tree for production issues:

Issue detected →
  ├─ Critical (site down, data loss)?
  │   └─ YES → Rollback immediately, investigate after
  │   └─ NO → Continue
  │
  ├─ Affects >10% of users?
  │   └─ YES → Fix within 1 hour or rollback
  │   └─ NO → Continue
  │
  └─ Can you fix in under 15 minutes?
      └─ YES → Fix and deploy
      └─ NO → Rollback, fix properly, redeploy

Real-World Example: Successful MVP Launch

Startup: Task management SaaS Launch: Product Hunt Preparation: Used this checklist

Pre-Launch Testing (2 days before):

✅ Load tested: Passed at 200 concurrent users
✅ Stress tested: Breaking point at 500 users
✅ Security scan: No critical issues
✅ Monitoring: All alerts configured
✅ Backups: Tested restore successfully

Launch Day:

Peak traffic: 380 concurrent users
Uptime: 100% (zero downtime)
Response time: P95 stayed under 300ms
Errors: 0.01% rate (1 error per 10,000 requests)
Signups: 1,247 in 24 hours

Issues Encountered:

Rate limit triggered for one user (bot) - worked as designed
Database connection pool hit 70% - within safe range
One 503 error during traffic spike - system recovered in 2 seconds

Outcome: Trending #3 on Product Hunt, zero major issues, smooth launch

What Made the Difference:

They tested everything on this checklist
They knew their breaking point (500 users)
They monitored in real-time
They had a rollback plan ready (didn't need it)

Conclusion: Preparation Prevents Disasters

You don't need to be perfect to launch. But you need to:

Know your limits
Handle errors gracefully
Monitor everything
Be ready to rollback

Time investment: 1-2 days of testing Cost: $20-50 in testing credits Value: Not losing your launch momentum

Use this checklist. Check off every item. Launch with confidence.

Download the Checklist

Want a printable version? Here's what to test before launch:

Critical (Must-Have):

Security testing (SQL injection, XSS, auth)
Load testing (handle expected traffic)
Error handling (graceful failures)
Monitoring & alerts configured
Database backups automated and tested

Important (Should-Have):

Rate limiting enabled
HTTPS with proper certificates
Health check endpoints
Environment variables configured
Rollback plan documented and tested

Nice-to-Have (If Time Permits):

Soak testing (find memory leaks)
Chaos testing (resilience)
Performance optimization
Advanced monitoring (APM tools)

Ready to Launch?

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