This will encompass things that I find useful and end up looking up later when I haven't coded in a while.

File Operations

Chmod file

File.chmod(0600, file)

Resource: https://stackoverflow.com/questions/22707040/change-permissions-of-file-in-ruby

Move file without fileutils

File.rename source_path, target_path

Resource: https://stackoverflow.com/questions/403239/how-do-i-move-a-file-with-ruby

Fix extensions not built errors

Run this command:

gem pristine --all

Resource:
https://stackoverflow.com/questions/48339706/ignoring-gems-because-its-extensions-are-not-built

Multiline comments

=begin
stuff
=end

Resource: https://stackoverflow.com/questions/2989762/multi-line-comments-in-ruby

Install specific version of a gem

Install the bcrypt_pbkdf package that came before version 2.0.

gem install bcrypt_pbkdf -v '<2.0'

RVM

Install 2.6.3 and use it by default

rvm install 2.6.3
rvm use 2.6.3 --default