Rules

Honor code

The leaderboard is for your own analysis. No AI assistants: no language models, chatbots, or coding agents to read scenes, write code, or produce flags. Nothing on the server can enforce this, so standings are trust based. You accept the honor code when you opt in to the leaderboard on your profile.

Do not post flags or full solutions publicly. Discussing methods is fine.

Everything is fictional

Port Meridian, its people, agencies, companies, drugs, journals, and documents are invented. Any resemblance to real people or organizations is accidental; tell us and we will rename it. The forensics scenes plant errors in synthetic manuscripts: an incompatibility under stated assumptions is grounds for a question, never proof of misconduct.

Exhibits

Data come in many open formats: .rds, .RData, SQLite, Parquet, SAS transport .xpt, fixed width text, JSON, spreadsheets, GeoPackage, VCF, PDF. R native files can run code when loaded in R versions before 4.4.0 (CVE-2024-27322). Use R 4.4.0 or later, download exhibits only from ctf.xera.ac, and check each file's SHA-256 checksum, shown beside it.

Disputes and errata

If you can defend a different answer from the Specification alone, the statement is at fault, not you. Write to the owner; a defensible alternative becomes a second accepted flag, the statement is fixed, and the change is listed on the scene.

Nothing expires

There are no events, deadlines, or seasons. Scenes stay open forever, and new ones open as they are written and reviewed.