Startup Guide

MVP Security Guide

Ship fast without getting hacked. The practical guide to security for founders who need to move fast but can't afford a breach.

The MVP Security Dilemma

You're caught between two startup-killing scenarios:

Too Little Security

  • • Data breach destroys trust
  • • Legal liability for user data
  • • Reputation damage is permanent
  • • Investors lose confidence

Too Much Security

  • • Never ship product
  • • Burn runway on compliance
  • • Competitors beat you to market
  • • Over-engineer before PMF

The solution: Minimum Viable Security—the smallest set of security measures that protects you from catastrophic risk while letting you move fast.

Minimum Viable Security (4-Hour Implementation)

1. Authentication That Actually Works

~1 hour

Don't build auth yourself. Use Auth0, Clerk, Supabase Auth, or Firebase Auth. These handle password hashing, session management, and OAuth correctly.

Don't
// Rolling your own auth
const hash = md5(password)
if (user.password === hash) {
  session.user = user
}
Do
// Use a proven auth provider
import { auth } from '@clerk/nextjs'

const { userId } = auth()
if (!userId) redirect('/sign-in')

2. Secrets in Environment Variables

~30 min

Never commit API keys, database passwords, or secrets to git. Use environment variables and .env files (gitignored).

Quick Audit

# Search for hardcoded secrets
grep -r "sk_live" --include="*.ts" .
grep -r "AKIA" --include="*.ts" .  # AWS keys
grep -r "password" --include="*.ts" . | grep -v "test"

3. Database Access Rules

~1 hour

The #1 cause of startup data breaches: database rules that allow public access. Configure RLS (Supabase) or Security Rules (Firebase) properly.

Test Your Rules

  1. 1. Create two test accounts
  2. 2. Log in as Account A, create some data
  3. 3. Log in as Account B
  4. 4. Try to access Account A's data
  5. 5. If you can see it, your rules are broken

4. HTTPS Everywhere

~15 min

Enforce HTTPS on all connections. Most modern platforms do this automatically, but verify.

  • Vercel/Netlify: Automatic, just verify
  • Custom domain: Use Cloudflare for free SSL
  • Add HSTS header: Prevents downgrade attacks

5. Run a Security Scan

~15 min

Automated scanners catch the obvious stuff you missed. Run one before launch and fix critical issues.

Run Free Security Scan

What Can Wait

These are important, but won't kill your MVP if missing on day one:

Rate limitingAfter you have traffic
Advanced loggingAfter you have users to monitor
Penetration testingAfter product-market fit
SOC 2 complianceWhen enterprise sales require it
Bug bounty programWhen you can afford payouts
Security team hireSeries A or later
Advanced WAF rulesWhen you're a target
Zero-trust architectureWhen you have multiple services

Common MVP Security Mistakes

Stripe secret key in frontend code

Impact: Attackers can charge any amount to any card
Fix: Move to server-side API route

Supabase RLS disabled for 'easier development'

Impact: Anyone can read/write all data in your database
Fix: Enable RLS, write proper policies

Admin routes without authentication

Impact: Anyone can access admin panel
Fix: Add auth middleware to admin routes

Git history contains old API keys

Impact: Keys exposed even after 'removing' them
Fix: Rotate all keys, use git-filter-branch to clean history

Debug mode enabled in production

Impact: Stack traces reveal code structure to attackers
Fix: Set NODE_ENV=production, disable debug flags

The ROI of MVP Security

4 hours

Time to implement Minimum Viable Security

$200K+

Average cost of a startup data breach

60%

of small businesses close within 6 months of a breach

Frequently Asked Questions

We're pre-launch with no users. Do we need security?

Yes, but minimal. Bots scan for vulnerabilities automatically—your empty database won't stop them from finding exposed endpoints. Implement the basics before sharing any public URLs.

Can't we just fix security issues later?

Security debt compounds. Fixing auth architecture after you have users is 10x harder than doing it right initially. The Minimum Viable Security items take 4 hours now vs. weeks later.

What if we get hacked anyway?

Have a response plan: 1) Take affected systems offline, 2) Identify what was accessed, 3) Notify affected users, 4) Fix the vulnerability, 5) Document what happened. Speed matters—don't figure this out during an incident.

Our investor wants SOC 2. Is that needed for MVP?

SOC 2 is for enterprise sales. If you're pre-PMF, it's premature optimization. Focus on basic security now, SOC 2 when you're closing enterprise deals that require it.

Ship Secure, Ship Fast

Check your MVP for critical security issues in 2 minutes. Fix problems before they become incidents.

Scan Your MVP Free

Last updated: January 2025