9flare

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• Details
• About this entry

9flare

https://codeberg.org/catfromplan9/9flare
Lightweight and extensible PoW captcha

9flare is a minimal, extensible proof-of-work CAPTCHA implementation written in C, inspired by Anubis. It operates as a FastCGI program, forgoing an integrated HTTP server in the interest of simplicity, and relies on nginx to forward cleared visitors to their destination via its error code fallback mechanism. Broad browser compatibility is a design priority, so you will experience no friction using 9flare with lightweight browsers such as NetSurf or Lynx. JavaScript is entirely optional, and all JavaScript is advertised as AGPLv3 to LibreJS.

Download

https://codeberg.org/catfromplan9/9flare/archive/v1.1.3.tar.gz

Categories

• Interface:web
• Library:Web
• Programming-language:C
• Runs-on:GNU/Linux
• Runs-on:Windows
• Runs-on:BSD
• Runs-on:OS X
• Runs-on:GNU/Hurd
• Use:system-administration

Licensing

License

Verified by

Verified on

Notes

License

AGPL-3.0-only

Verified by

ksiewicz

Verified on

29 May 2026

Notes

https://codeberg.org/catfromplan9/9flare/src/branch/master/LICENSE

Leaders and contributors

Resources and communication

Software prerequisites

Kind	Description
Required to use	GnuTLS OR libsodium OR OpenSSL

Entry

"AGPL-3.0-only" is not in the list (ACEL, AFL-3.0, AGPL-1.0, AGPL-1.0-or-later, AGPL-3.0, AGPL-3.0-or-later, AGPL-3.0-or-later-with-exception, AGPL-3.0-with-exception, AGPLv1orlater, AGPLv3, ...) of allowed values for the "License" property.

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