Below are the currently agreed-upon development practices for writing MojoMojo code. Discussion are welcome at discussion.
In Perl code, abide by perlstyle: use 4-space indentation, no tabs, spaces around operators etc. Really read
Follow the Perl Best Practices. Ideally, your code should pass Perl::Critic on at least the gentle setting.
In Template::Toolkit code, use 4-space indentation for HTML code, and 2-space indentation for TT code. See rationale and examples at Indenting TT and HTML.
Line length is 120 characters per line (this happens to also be about how many characters fit in the GitHub UI at 100% zoom). Nobody really uses 80-character lines any more, many existing lines are already longer than 80 characters (and perltidy wraps them horrendously), and we don't print out code. If you are using Perl::Tidy to automatically format your code, you can set a different line length via:
perltidy --perl-best-practices -l=115
However, in the tradition of Catalyst code, use of perltidy is discouraged. For example, Catalyst::Stats does not vertically align on '.', and Catalyst::Test does not wrap at anything less than 112 characters.
Marcus' last word on this is "In general I want catalyst style code, if people run perltidy on stuff they write, I don't mind. I just want a readable codebase that is easy to contribute to."