The Arena
Real CVEs and planted bugs, set in readable code. Flag the lines, then defend your reasoning in prose.
Find the vulnerability.
Write the fix.
A white-box training ground: read real vulnerable code in eleven languages, mark the lines that bite, and explain the flaw in your own words for semantic assessment.
The Academy
Long-form write-ups that turn each class of flaw into something you can recognise on sight — from OWASP Top 10 to COBOL mainframes and Fortran HPC kernels.
Semantic Assessment
Explain the vulnerability in your own words. Claude grades meaning, not keywords — partial credit for partial insight.
Eleven languages, one discipline
GoRustNode.jsC#CC++AssemblyPerlCOBOLFortranFlutter