Erlang/OTP 26 will soon be released by OTP team and unfortunately broke the compilation of Cowlib, which is a dependency for both Cowboy and Gun.

Users willing to upgrade to Erlang/OTP 26 or above will therefore need to ensure that they use the right version of Cowboy or Gun. The versions that first supported Erlang/OTP 26 are as follow:

• Cowboy 2.10.0
• Gun 2.0.1
• Cowlib 2.12.1

A small number of fixes has also been made at the same time but the main change is support for Erlang/OTP 26.

You can donate to these projects via GitHub Sponsors.

As usual, feedback is appreciated, and issues or questions should be sent via Github tickets. Thanks!