Built with Replit
Replit wrote the checklist. Nobody read it back to your app.
They publish a security checklist for vibe-coded applications, and it is a good one. A checklist tells you what to want. Whether your app has it is a separate question, and answering it means reading the code.
Replit is a trademark of its owner. This page quotes their public documentation to explain a scope of work. There is no partnership, endorsement or affiliation in either direction.
The line Replit draws
Their half, and yours.
Replit sets this out formally, which is more than most platforms do. Both columns below are taken from that document.
Replit’s side
- The operating system, runtimes and development environment
- Storing secrets, and not storing them in plaintext
- Edge protection, encryption in transit and at rest
- Detecting vulnerable dependencies
- Generating the code, when the Agent writes it
Yours
- “Verifying correctness, security, and licensing of Agent output, including third-party dependencies it introduces.”
- “Always use Connectors and the Secrets feature to ensure proper storage of secrets.”
- “You are responsible for choosing who can view, edit, or remix each app… view secrets, and so on.”
- “The data that is consumed, created, or displayed by the application.”
- Application-level logging and monitoring: errors, business events, user activity.
Replit: shared responsibility model — worth ten minutes of your time whether or not you ever buy anything from me.
Their checklist
We are looking for the same things.
Replit’s checklist names what people building this way get wrong. I did not invent my list to sell an audit; it is the same list, arrived at from the other side.
| What Replit lists | What I call it |
|---|---|
| Exposing API keys in frontend code | Hardcoded keys |
| Storing sensitive data in browsers instead of using Secrets | Console and data leakage |
| Improper error handling that leaks database messages | Console and data leakage |
| Outdated dependencies — “most vulnerabilities come from outdated libraries” | Supply chain |
Replit also gives you scanners for dependencies and known patterns, and you should run them. What no scanner reaches is the fifth item on my list: a permission rule that exists, runs, and lets the wrong person through. Replit: security checklist.
Start here
Settle the easy ones yourself.
Each of these takes a couple of minutes and needs nothing from me.
Decide who can open the published app
Replit lets a published app be public, password protected, workspace only or invite only. Open the publishing settings and confirm the setting matches who the app is actually for.
Read your own app the way a stranger would
Open the published URL in a private window, view the source, and search it for keys and tokens. Their checklist is blunt about this one: API credentials should always remain server-side.
Ask what the Agent was told about permissions
Replit asks you to explain your access-control model to the Agent. If that conversation never happened, the rules the Agent wrote are the rules it guessed.
Break something on purpose and read the error
Submit a malformed request and look at what comes back. A database message reaching the browser is on their list of common mistakes, and it is the map an attacker reads first.
The publishing access setting is the one people are most often surprised by — Replit documents the four options. To hand the deeper pass to your own AI tool, the five-flaw prompt is free too.
The audit
Someone has to do the reading.
Replit tells you what your half of the job is. It cannot do that half, and neither can a scanner, because most of it is judgement about your business rather than patterns in your code.
That is the whole product: the standard I hold myself to is published, including where it stops.
€350 + VAT · 48 hours
Your half, read by a senior engineer.
Every finding with the evidence behind it, what it would cost you, and a prompt you can paste back into the Agent.
€430.50 including VAT.
Start here
Tell me what you have running.
Five questions. If a Replit app this size does not warrant the audit yet, you will hear that first.