File View

Switch to Open Files view, on panel settings enable Tree Appearance -> Compact Directories, Open Files with Single Click, and Always Select Opened File. This gives a project view filtered to your working set of files, and by selecting files when they open it’ll ensure the tree stays as expanded as possible. Now hit Preferences and under Editor Tabs set Tab placement to none, and bump up the Tab limit to 100 or so to keep it from closing things early.

Ruby with ASDF

For whatever reason, by default it only found rubies installed via rbenv, and not asdf.

It can be manually added via Preferences, Ruby SDK and Gems, +, Interpreter…, and browsing to ~/.adsf/installs/ruby/VERSION/bin/ruby.

However, our app’s somewhat older ruby (2.6.9) and rails (5.2) is still hiccuping on things like rubocop.