Erlang/OTP libraries/modules replaced by third party projects

e.md

I'm looking to collect information on why certain functionality found in Erlang/OTP is usually handled instead by a third party library in people's projects.

This could be bugs, missing functionality, poor interface, performance, etc.

Examples off the top of my head that need expanding on are:

• httpc
• httpd
• http_uri
• reltool

Please comment on this gist with libs and reasons, even if you aren't sure they are accurate or still accurate today.

I also guess that not everybody are happy with the way how we do configuration. sys.config files and application:get_env sometimes don't fit our needs: config files should be written in erlang syntax; sometimes configs should have some other logical structure, not just <application>.<key>.

Yes, calendar module is a disaster in the user experience sense. It should really be replaced.