What is the correct way to specify the Ruby version in a Rails app, using RVM, that will be deployed on Heroku?

Question

The RVM Best Practices state that, to connect a project to a specific Ruby version, you should specify that version in the project-specific rvmrc file.

This SO answer states that, in most situations, you should use specify the Ruby version in the .ruby-version file.

Heroku says you should specify the Ruby version in Gemfile.

What is the correct way to specify a Ruby version, using RVM, if the app will be deployed on Heroku?

score 4 · Accepted Answer · answered Sep 13 '13 at 15:37

4

.rvmrc is deprecated and you should use .ruby-version instead.

But Heroku does not pay attention to the .ruby-version. Heroku wants to have it in the Gemfile. So I think you should use both: .ruby-version (for you) and Gemfile (for Heroku).

answered Sep 13 '13 at 15:37

spickermann

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`.rvmrc` is not deprecated - that word is not used in the message, the message is to make you aware, it does not state that `.rvmrc` will no more be used – mpapis Sep 13 '13 at 22:14

score 2 · Answer 2 · answered Sep 13 '13 at 15:32

2

You need to place it in the Gemfile for Heroku's sake, but if you're using a version manager, then you'll need to use something else for the sake of the version manager. I think the SO answer makes sense in that regard (i.e. the .ruby-version file).

answered Sep 13 '13 at 15:32

Peter Alfvin

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score 1 · Answer 3 · answered Sep 13 '13 at 18:34

Check https://rvm.io/workflow/projects - it says you can use Gemfile to specify ruby version for RVM like this:

ruby "1.9.3"

or something more complicated:

ruby File.readlines(".ruby-version").first.strip

and then in .ruby-version:

1.9.3

this way it will work also with other ruby environment managers like chruby

What is the correct way to specify the Ruby version in a Rails app, using RVM, that will be deployed on Heroku?

3 Answers3