83defects found
Find bugs and vulns code review misses
Code review reads the diff. Heal runs your product, in a sandbox that replicates production, and hunts for reproducible bugs, runtime vulnerabilities and performance issues. Each one comes with the failing test that proves it.
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“Found bugs our code review missed.”
Twenty, on X
Code review reads the diff. Heal runs the product.
Keep your code reviewer: it reads every pull request. Run heal on the whole product, weekly or before a release, and it hands back what a diff can't show, each defect with the failing test that proves it.
| Trying to catch… | AI code review | heal |
|---|---|---|
| What it sees | The diff of one pull request. A bug between untouched code, config, data and a third-party service is outside it. | The running product: every feature, its data and the services it calls, changed or not. |
| Is it real? | Flags a pattern that looks wrong. Whether it can be reached, and what happens when it is, is left to you. | Proves it: a test fails twice, then fails again when heal re-runs it itself. What it cannot reproduce, it does not file. |
| What you get | Comments on lines of code. | A defect with its steps, the captures, and the failing test that turns green once it is fixed. |
| Security | Matches code that looks like a vulnerability. | Fires the real exploit at the sandbox, signed in as two people, and reports what came back. |
| Payments, mail, third-party APIs | Sees the call in the code, never what the service answers. | Mocks or emulates them in the sandbox, then replays them failing, slow, or answering twice. |
What it sees
The diff of one pull request. A bug between untouched code, config, data and a third-party service is outside it.
The running product: every feature, its data and the services it calls, changed or not.
Is it real?
Flags a pattern that looks wrong. Whether it can be reached, and what happens when it is, is left to you.
Proves it: a test fails twice, then fails again when heal re-runs it itself. What it cannot reproduce, it does not file.
What you get
Comments on lines of code.
A defect with its steps, the captures, and the failing test that turns green once it is fixed.
Security
Matches code that looks like a vulnerability.
Fires the real exploit at the sandbox, signed in as two people, and reports what came back.
Payments, mail, third-party APIs
Sees the call in the code, never what the service answers.
Mocks or emulates them in the sandbox, then replays them failing, slow, or answering twice.
What people say about heal.
Teams that ran heal on their own code, in their words.
- Twenty@twentycrm
Our friends at @healdevHQ ran their tool on Twenty and found bugs our code review missed. Reviewing the friendship but recommending the tool.
Sep 24, 2026view on x 
Florian Bienefelt@FBienefeltShoutout to @healdevHQ for creating a super strong bug hunter I can just run on our entire product, and output a list of issues with clear reproductions, recordings, ready for me to hand to my own agents. Running this weekly now to fight bugs and slop.
Oct 8, 2026view on x
Mark Ridgeon@RidgeonM@healdevHQ is a game-changer. Instead of just reading your code, it learns how to run your app and uses that runtime to catch and verify deep bugs/vulns. Big thumbs up!
Oct 7, 2026view on x
See heal run on open-source repos.
Heal built a production-like environment for each repo and uses it to find and validate reproducible defects.
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odoo/odoo55k
165defects found
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127defects found
Sandbox your app and find runtime issues
Heal learns how to run your environment and mocks what cannot run. It reads your code for suspicions, like a reviewer would, then runs each one against the sandbox: only what a test reproduces is filed.
Reads your code, maps your architecture.
- checkout6 screensroutes/checkout.tsx:44
- billing4 screensfeatures/billing/plans.tsx:12
- search3 screensfeatures/search/index.ts:8
- onboarding5 screensroutes/start/[step].tsx:21
- account4 screensroutes/account.tsx:30
- admin7 screensapps/admin/src/main.tsx:5
What E2E tests and scanners miss
Untested integrations, edge cases, services disabled in staging, hard-to-mock async services. And everything where you need a runtime.
Heal runs these, on the sandbox:
- schemathesis
- ZAP
- dalfox
- jwt_tool
- nuclei
- semgrep
- trufflehog
- sqlmap
- and more…
| Trying to catch… | E2E tests and scanners | heal |
|---|---|---|
| Edge cases | E2E runs the happy path against staging. Requests that fail, slow down or come back with a field missing are never staged. | Walks every flow again with the world failing, and files the screen that says “nothing here” when the server broke. |
| Services turned off in staging | Payments, mail and third-party calls are switched off. | Mocks them in a production-like sandbox, so the flows behind them run for real. |
| Validated runtime security issues | A static scanner reports a pattern in code that may never be reachable, and cannot tell you if it is. | Fires the real exploit at the sandbox, signed in as two people, and reports only what a test reproduces. |
| Missing routes | Dead pages, assets that do not load and screens no feature names are nobody’s test. | Crawls every link once, over the whole running app. |
Edge cases
E2E runs the happy path against staging. Requests that fail, slow down or come back with a field missing are never staged.
Walks every flow again with the world failing, and files the screen that says “nothing here” when the server broke.
Services turned off in staging
Payments, mail and third-party calls are switched off.
Mocks them in a production-like sandbox, so the flows behind them run for real.
Validated runtime security issues
A static scanner reports a pattern in code that may never be reachable, and cannot tell you if it is.
Fires the real exploit at the sandbox, signed in as two people, and reports only what a test reproduces.
Missing routes
Dead pages, assets that do not load and screens no feature names are nobody’s test.
Crawls every link once, over the whole running app.
Every defect comes with the test that proves it
What you get, what you should get, the screen it failed on, how it happens, where to look in the code — and the failing test that reproduces it.
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Point it at your repo.
Connect GitHub and get your report. It runs locally or in the cloud.
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