Sample travis.yml for RubyGems.

.travis.yml

language: ruby
bundler_args: --retry=3 --jobs=3
cache: bundler
sudo: false
rvm:
  - 2.3
  - 2.2
  - 2.1
  - 2.0
  - 1.9.3
  - jruby-19mode
  - jruby-head
  - ruby-head
env:
  global:
    - JRUBY_OPTS="-J-Xmx1024M --debug"
matrix:
  allow_failures:
    - rvm: 1.9.3
    - rvm: jruby-19mode
    - rvm: jruby-head
    - rvm: ruby-head
  fast_finish: true

• cache: bundler Source, if you put gems under vendor/, read this warning 🙇
• ⚠️ If you have any script using sudo, remove line 4. More info
• - JRUBY_OPTS="-J-Xmx1024M --debug" from rails/rails 🌠
• 1.9.3 allows failure because support for 1.9.3 has ended 😢
• fast_finish: true will mark your build as "passed" as soon as all builds are passed except ones from allow_failures More info

This .travis.yml will test latest Ruby 2.0.0, 2.1, 2.2.1.

If you want to drop 1.9.3 support, add spec.required_ruby_version = '~> 2.0' in your-gem.gemspec and use this .travis.yml instead:

language: ruby
bundler_args: --retry=3 --jobs=3
cache: bundler
sudo: false
rvm:
  - 2.3
  - 2.2
  - 2.1
  - 2.0
  - jruby-head
  - ruby-head
env:
  global:
    - JRUBY_OPTS="-J-Xmx1024M --debug"
matrix:
  allow_failures:
    - rvm: jruby-head
    - rvm: ruby-head
  fast_finish: true

Awesome.