Features:

• Arbitrary categories and challenges.
• Scoreboard with optional multiple team types.
• Manual or automatic free-text submission marking.
• Challenge hints.
• Team progress page.
• Challenge overview page.
• Limit category and challenge exposure to certain times.
• Challenge reveal on parent challenge solve (by any team).
• Optional signup restrictions based on email regex.
• Local or Amazon S3 challenge file upload.
• Optional automatic MD5 append to files.
• Admin management console with competition overview.
• Create/edit front page news.
• Arbitrary menu items and internal pages.
• Optional total number and time-based submission throttling.
• User management with IP correlation.
• Internal log for catching exceptions.
• reCAPTCHA support.
• User-defined or auto-generated passwords on signup.
• User/Email/IP search.
• Configurable caching.
• Caching proxy (like Cloudflare) aware (optional x-forwarded-for trust).
• Optional separate domain for static files.
• Segment analytics support.
• SMTP email support. Bulk or single email composition.
• TOTP two factor auth support.
• CTF Time compatible JSON scoreboard.
• Self-serve and admin password reset.

and more ...

Mellivora scales well on Amazon Elastic Beanstalk and has support for S3 file storage.