I18n Migrations

We help you manage your locale translations with migrations, just the way Active Record helps you manage your db with migrations.

There are several tools out there that allow you to dynamically store / load / translate strings in your app. We prefer to deploy our app with static files using the excellent i18n gem. But how to translate?

Our flow is:

  1. Use a migration to make a change (add/remove/update/move) to your translations locally. In this state, we will use google translate to quickly guess at translations.
  2. When ready to deploy, push these changes to google spreadsheets, one for each translation, there, your translators can fix google translate's mistakes.
  3. Pull to replace your translations with what's in those google spreadsheets.
  4. Migrate to play back any changes after pulling / merging / etc.


Add this line to your application's Gemfile:

gem 'i18n-migrations'

And then execute:

$ bundle

Or install it yourself as:

$ gem install i18n-migrations

From your project file, you'll want to run

$ i18n-migrate setup

This will create a config file you can edit.


Let's imagine that your config file look like this:

migration_dir: i18n/migrate
locales_dir: config/locales
main_locale: en
- es

In your project file, you should then have all your english terms in config/locales/en.yml

To create a new locale (like es.yml):

  1. Translate all the terms w/ google translate

    i18n-migrate new_locale es

  2. Create a spreadsheet that is world editable (for now). You'll want to add the link to it to your config file. It should look like:

    | key | en | es | notes |

  3. Push this to your google spreadsheet (the -f means it won't try to pull first)

    i18n-migrate push -f es


After checking out the repo, run bin/setup to install dependencies. Then, run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release to create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.


  1. Fork it ( https://github.com/[my-github-username]/i18n-migrations/fork )
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request