Is a gem ready for Rails 4 or 5?

Rails 4: 614 ready, 38 not ready, and 433 unknown
Rails 5: 157 ready, 12 not ready, and 916 unknown
Name Status Rails 4 Notes Rails 4 Status Rails 5 Notes Rails 5 Status or notes updated
lograge unknown ready

5.0 from v0.4.0, 5.1 from v0.5.0, 5.2 from ? mentioned in commit messages though

2 days ago
nokogiri ready

Does not depend on Rails.

ready

does not depend on Rails

2 days ago
puma ready

-

ready

default server for Rails

2 days ago
pry-rails ready

-

ready

5.0 from v0.3.3, 5.1 from v0.3.7, 5.2 from v0.3.9, 6.0 (!) from v0.3.9

2 days ago
quiet_assets ready

-

not ready

See https://github.com/evrone/quiet_assets#deprecation

2 days ago
rack-attack ready

-

ready

5.1 from v5.1.0, 5.2 from v5.3.0

2 days ago
rails_12factor ready

-

ready

This gem isn't needed for New Rails 5 apps. There is doc in the README for migrating from a Rails 4 to 5 app: https://github.com/heroku/rails_12factor

2 days ago
ranked-model ready

Recent activity and rails4 branch merged in July 3rd. (https://github.com/mixonic/ranked-model)

ready

5.0, 5.1, 5.2 from v 0.4.2

2 days ago
react-rails ready

It works in our rails 4.1.6 app.

ready

5.2 from v2.4.5, 5.1 from v2.1.0, 5.0 from v1.7.1 (at least... bugfix for v 5.0 mentioned in changelog)

2 days ago
redis-namespace ready

Does not depend on Rails.

ready

does not depend on Rails

2 days ago
responders ready

since gem version 1.0.0.rc

ready

5.0 from v2.1.1, 5.1/5.2 from v2.4.0

2 days ago
rollout ready

Working with '~> 1.2'

ready

does not depend on Rails

2 days ago
roo ready

Does not depend on Rails

ready

does not depend on Rails

2 days ago
rubocop ready

Does not depends on Rails

ready

does not depend on Rails

2 days ago
scenic ready

-

ready

5.2 from master, 5.1 from v1.4.0, 5.0 from v1.1.0 (at least, could be earlier)

2 days ago
sdoc ready

does not depend on Rails

ready

does not depend on Rails

2 days ago
shoulda ready

per README for 4.2

ready

per README, at least for 5.0

2 days ago
sidekiq ready

source

ready

does not depend on Rails

2 days ago
sinatra ready

Does not depend on Rails.

ready

does not depend on Rails

2 days ago
spring ready

It's Rails core.

ready

from gem version 2.0.0 - though there is this bug: https://github.com/rails/spring/issues/485

2 days ago