erlfmt

Author of erlfuzz here. I'm part of a team at WhatsApp that, among other things, builds tools to improve developer efficiency for Erlang developers, especially at scale. erlfuzz is intended to make it safer for us (and others) to hack on the compiler and VM by catching early any bugs that might be introduced. That it also found a bunch of bugs that had been hidden for years is a very nice bonus and validates the approach. Other recent projects open sourced by my team: - a massive speedup of a common static analyzer for Erlang (https://github.com/erlang/otp/pull/5997) - a type checker for Erlang (https://github.com/WhatsApp/eqwalizer/) - an automated code formatter for Erlang (https://github.com/WhatsApp/erlfmt) - a grammar to easily parse Erlang (https://github.com/WhatsApp/tree-sitter-erlang/)

They also made a fantastic auto-formatter for Erlang code https://github.com/WhatsApp/erlfmt so evidently they have resources cleared for doing generally useful Erlang stuff.