Contact

Get in touch

We are a small team and we read everything that comes in.

General enquiries

Questions about the platform, billing, partnerships or press.

Ask on the ticket itself — the maintainer and other solvers can answer there, and the next person gets the answer too.

Found a vulnerability, or want your data removed? Write to us and we will respond within 30 days.

We aim to reply to email within two working days, and to review challenge submissions within a day. Security reports are triaged first.