Build fast, but don’t build blind.

Whether you’re using Replit, Windsurf, Cursor, GitHub Copilot, or just coding at speed, you’re likely missing some key security steps. This checklist helps you build with confidence, keeping security in mind—without slowing you down.

AI coding tools often skip critical context like how users interact with your app, where trust boundaries lie, or how business logic could be misused. They can suggest insecure patterns—like hard-coded secrets, poor input validation, or missing access controls—and never raise a red flag. Even worse, they might generate functional code that quietly introduces serious vulnerabilities.
And once your app is live, you’re done, right? Not quite. Security isn’t a one-time fix. It needs regular updates, monitoring, and maintenance to keep your app as secure as it was on day one.

Advise Secure helps software teams of all sizes embed practical security into their development flow. We review your codebase, systems, and pipelines to help you identify weak spots and fix them without adding friction.

🧩 1. Design: Before You Code

Build security in from the start. In almost all AI tools, you can provide them the rules on how your code should function, how it should handle data, how users should be able to use the system etc. The more information and more specific you can be will ultimately bring a better outcome. Prompting the AI to make memories of some of this logic or writing a text file of rules and then telling the AI to always consider your text file as part of everything it does can be very valuable.

Understand your users and roles
Identify different user types (e.g. admin, guest, service accounts) and restrict access accordingly. Have a good understanding of what a user can or can't do. e.g. a user should not be able to see or update other user's information.
→ Prevent privilege escalation and misused features.

Map out trust boundaries
Define where data moves between users, systems, and third parties. Again provide prompts that advise how or when data can flow.
→ Helps with threat modelling and future architectural changes.

Identify reliance on third parties (APIs, plugins, services)
Document what external tools you rely on (e.g. OpenAI APIs in Replit). It will be important that you maintain the relationships with these third parties, know where the credentials are kept and your obligations to keep them up to date. e.g. almost every third-party service makes changes to its API. It is up to you to track emails from the third-party service and understand what and when changes need to be made before an incompatible change is made.
→ Enables monitoring for outages, security risks, and updates.

Design for abuse cases
Think about how features could be misused (e.g. someone uploading malicious document, or trying to access another users record - record 1, record 2 etc.). Tell the AI you are worried about these problems and to again make a memory of it or consider it in each prompt.
→ Avoids feature-level risks like escalation of privileges or data exposure.

Document intended data flow
Write out what’s expected to happen and what isn’t. A data flow diagram or UML diagram can go a long way in telling the AI what to build
→ Makes reviewing and securing code easier later on.

🏭 2. Manufacturing: As You Code

Catch the bugs while you’re building. This is when code is being made so its important you are telling the prompt to consider security and the more you know from your design stage about how it should work, the more you can help prompt the AI to make good decisions.

Use Test Driven Design
If you have designed well and have a well-defined project, you can ask the AI to build "Unit Tests" or "Integration Tests" that prove that logic, ideally before code is written. For example I make a calculator app and I know a + b = c is part of the logic. I can have the AI write a bunch of tests e.g. 5 + 6 and have it test that the output is 11. If any other output is produced, then you know something has not worked.

Use Static Code Analysis and Software Composition Analysis Security Tools
Tools exist that look at your code to identify coding vulnerabilities or weaknesses in dependencies in your code.
If you are using tools like Cursor and Windsurf that still allow you to look at and change code, it is easy to install these tools and run them to check for issues.
Some examples include Snyk and Semgrep and they have free/cost effective models for small private projects.
If using Replit, you get the ability to use built in tools such as the Security Scanner that can help check for vulnerabilities.

Apply business logic validation (e.g. against IDOR)
Ensure users can’t act on data they don’t own (e.g. editing another user's profile via direct object access).
→ A common issue in fast-built apps, especially in low-code setups.

Defend against injection attacks
Validate and sanitise all user input to stop SQLi, XSS, etc.
→ Particularly important if AI-generated code is used without oversight.

Add logging for key security events
Log things like successful/failed logins, privilege changes, interesting events and anything that would make sense to your app from a security side. Remember to track which  user did the action, what their IP address was and what the event was
→ Helps detect and respond to attacks quickly.

Write meaningful error handling
Don’t expose stack traces or system internals to the user.
→ Prevents accidental leakage of sensitive info.

Secure secrets and config
Never hard-code API keys or secrets—even if AI tools suggest it! Use secret managers.
→ Common pitfall when copy-pasting from AI platforms like Replit.

🚀 3. Deploy: After It Ships

Stay protected in production.

Keep third-party dependencies up to date
Ask the AI prompt to update your dependencies, or use tools like Dependabot or npm audit
→ Prevents known vulnerabilities from being exploited.

Review application and infrastructure logs regularly
Set up alerts for suspicious behaviour.
→ Essential for catching threats early and responding fast.

Limit exposed services and ports
Only make public what’s necessary (e.g. hide dev tools, admin endpoints).
→ Reduces attack surface.

Use HTTPS and secure headers
Make sure everything is encrypted in transit and adds headers like CSP, HSTS, and X-Frame-Options.
→ Protects users and prevents common browser-based attacks.

Backups and recovery plan
Can you restore from backup if something goes wrong?
→ Basic but often overlooked, especially in fast-moving teams.

🔧 How Advise Secure Can Help

Building securely doesn’t mean slowing down. At Advise Secure, we help teams using tools like Replit, Windsurf, and Copilot to:

• • Conduct Penetration Testing 
  • Perform code reviews and logic validation checks
  • Threat model new features or AI-generated code
  • Set up logging, alerting, and monitoring that actually works
  • Recommend practical improvements without disrupting your workflow

  • Review app and infrastructure security before and after deployment