Most startups think about security after something goes wrong. A breach at an early stage can be fatal. These ten checks can be completed in a weekend.

1. Enable HTTPS Everywhere

Every page must be served over HTTPS. Get a free TLS certificate from Let's Encrypt. Redirect all HTTP traffic and implement HSTS.

Test it: Enter your domain in our free scanner to check your HTTPS and HSTS config right now.

2. Configure HTTP Security Headers

At minimum set: Content-Security-Policy, Strict-Transport-Security, X-Frame-Options: DENY, X-Content-Type-Options: nosniff, and Referrer-Policy.

3. Use Parameterised Queries

Never build SQL queries by string-concatenating user input. Always use parameterised queries or prepared statements.

4. Hash Passwords Correctly

Use bcrypt, Argon2, or scrypt. Never use MD5, SHA1, or SHA256 for password hashing.

5. Rate-Limit Auth Endpoints

Prevent credential stuffing and brute-force attacks against your login, registration, and password-reset endpoints.

6. Apply Least Privilege

Every component — database users, API keys, cloud IAM roles — should have the minimum permissions needed. Audit quarterly.

7. Keep Dependencies Updated

Enable automated updates (Dependabot, Renovate). Subscribe to security advisories. Budget time each sprint for patching.

8. Audit Cloud Storage Permissions

Before launch, audit every bucket. Ensure no sensitive data is publicly accessible. Use signed URLs for private objects.

9. Set Up Logging and Alerting

Log all auth events, access control failures, and sensitive data access. Alert on anomalous patterns.

10. Write an Incident Response Plan

Document what you'll do if you discover a breach. Who contains it? Who notifies users? A one-page plan written in advance means you'll respond faster.