Building Secure Web Apps: A Practical Checklist

Security is a shared responsibility. Start with threat modeling early and revisit it as features evolve. Enforce secure defaults: strict CSP, secure cookies, input validation, and the principle of least privilege for services. Automate testing: run SAST, dependency scanning, and container image checks in CI. Include security-related tests in acceptance criteria. Prepare an incident response plan and run tabletop exercises so teams can respond effectively when issues occur.

Embed Security Into Delivery

Shift security left by integrating scanning and threat modeling into sprint planning and CI pipelines. Verify assumptions with regular penetration tests and include security criteria in your definition of done.

Authentication Best Practices

Implement Multi-Factor Authentication (MFA) and enforce strong password policies. Use standard protocols like OAuth2 and OIDC instead of rolling your own auth. Regularly rotate API keys and secrets, and never commit credentials to version control systems.

Regular Security Audits

Schedule third-party security audits at least annually. External eyes often catch vulnerabilities that internal teams miss due to familiarity with the code.