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async function fetchUser(id) {
const q = “SELECT * FROM users WHERE id = ” + id;
// CRITICAL: SQL injection vulnerability return db.run(q);
}
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80+ Detection Rules
Hand-researched patterns built from OWASP, CWE, Google engineering guides, and real-world post-mortems.
SQL injection, XSS, eval(), hardcoded secrets, weak hashing, SSRF, path traversal, command injection, insecure deserialization.
Null dereferences, off-by-one errors, wrong comparisons, missing returns, infinite loops, type coercion traps, swallowed exceptions.
N+1 queries, SELECT *, nested loops, blocking I/O, missing indexes, string concat in loops, DOM thrashing, no memoization.
No error handling, magic numbers, God functions, callback hell, global variables, missing input validation, dead code.
JS: var hoisting, prototype pollution. Python: mutable defaults, bare except. PHP: extract(), globals. SQL: LIKE leading wildcard.
Zero API calls. Runs entirely in your browser using a compiled rule engine. Results in under 100ms regardless of code size.
12 Languages Supported
Language-specific rules for each — not a generic one-size-fits-all approach.
Instant Review in 4 Steps
No server. No API key. No waiting. Runs locally in your browser using a compiled rule engine.
Paste any snippet, function, or class. Any size — the engine handles it instantly.
Pick from 12 languages. Unlocks language-specific rules like PHP’s extract() or Python’s mutable defaults.
80+ regex and pattern rules run against your code in milliseconds. No network, no API, works offline.
Issues show severity, line number, explanation, and exact fix. Copy the full report or fix inline.
Questions
About the tool, the rules, and privacy.
No. The review engine runs 100% in your browser — no server calls, no API, no data transmission. Your code never leaves your device. The only network requests are loading the page fonts.
ESLint requires npm install, config files, and project setup. SonarQube is enterprise software. This is a paste-and-go zero-setup tool for quick reviews — great for reviewing code snippets, PR checks, or learning what patterns to avoid.
AI APIs have latency, costs, rate limits, and require your code to be sent to a third-party server. A rule-based engine is instant, private, free forever, and — for well-defined security patterns like SQL injection — actually more reliable than AI which can miss patterns or hallucinate fixes.
Yes — no static analyser is perfect. This tool catches common patterns but cannot understand business logic, complex multi-file interactions, or runtime behaviour. Use it as a first-pass check, not a replacement for thorough code review or testing.
Yes. We plan to add framework-specific rules (React, Laravel, Django), accessibility checks for HTML, and a diff review mode. Subscribe to the newsletter to get notified when new rules ship.
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