How do I change the default gemfile created with 'rails new' command?

Question

I have recently experienced an issue where I must add the following to my gemfile:

gem 'execjs'
gem 'therubyracer'

I must do this to avoid a javascript runtime error that occurs when starting the rails server. I would like to have this modification added to all new gemfiles created with the rails new command.

Answer 1

You're looking for application templates.

Answer 2

Rails documentation on Application Templates

If you want the option to customize each app individually instead of having a rigid template, a really good option is Rails Composer. It prompts you about common gems during setup, and it nails a lot of the more common gems.

Finally, if you like Rails Composer, but want to be able to re-use application templates, check out Rails Apps Composer. I haven't looked into this too much, but it seems to give you a lot of flexibility while doing most of the heavy lifting for you.