Finally, after a while I started applying into development projects some automated tests using Travis CI. Thanks to Travic CI documentation integration of projects was rather painless.
So far following projects are running in Travis CI:
In both of these projects I needed to take advantage of Travis features. Namely I needed to utilize gemfile feature in both. In additona in ngannotate-rails project it was necessary to opt also for build matrix in order to test gem functionality with both sprockets 2.x and 3.x versions.