A good ROR developer should also have a working knowledge of various concepts like models, migrations, validation, and associations.
When the developers need to test particular app features, RSpec comes as the most popular and irreplaceable choice for all apps built with Ruby on Rails.
You need to ensure the working knowledge of developers with RSpec testing.
In case the developers need to use Ruby on Rails for building new API, a familiarity and working knowledge of API and JSON format comes as very necessary and handy.
Having a detailed knowledge of the protocols and norms of HTML5 is invaluable for front-end web development.
CSS which refers to the Cascading Style Sheets is very common front-end language used widely for building web apps.
Having a sound knowledge of CSS is important to master the challenges of UI development.
A web developer should also have familiarity with the major database languages and libraries.
In spite of the fact that ActiveRecord utilizes the SQL, developers having in-depth knowledge of SQL will enjoy the better understanding of the logs.
MySQL & PostgreSQL are other two open-source database management systems with huge popularity. The developers with a solid knowledge of these databases can help fast-pacing the development.
In-Depth knowledge of NoSQL database especially comes to your aid when you need to work with a big distributed data set.
Git is a globally popular repository that allows the developers to maintain a complete code deposit just as the local app.
Are your developers familiar with some of the top tools for deployment and implementation as well?
In that case, you have an extra edge. Some of the key tools they should know include Jenkins, CI, Vagrant, Prometheus, Capistrano, Docker, and Heroku. The developers should also be able to work with project management software like Asana, Basecamp, Github, Pivotal, Trello, and AceProject. All these tools and software knowledge ensure additional expertise for the ROR developers.