What Ruby and Rails Developers Ought To Know?

What should someone know as an Entry Level, Mid-level, and Senior Developer working with Rails? Across the board: theoretical knowledge, development tools, gems and more. What issues usually are at the interview?



  • Analyse and profile an application for performance and memory issues
  • Analyses and profile an application for security issues
  • Understand database modeling and query analysis
  • Tune a production deployment (Passenger, Thin, Apache etc)
  • Understand and use Ruby metaprogramming
  • Mentoring skills
  • Communication skills
  • Planning and Estimation


  • Setup and deploy a Rails App for production
  • Understand the Rails stack - callbacks, filters, plugins, engines, gems, rack
  • Understand and use Active Record associations
  • Understand and use scopes to define model abstractions
  • Define tests using Cucumber and rSpec
  • Understand and use Object Orientation
  • Understand and use Design Patterns (explain what they are, know some basic patterns)

Entry Level

  • Create and setup a Rails environment
  • Use generators to create models, controllers and migrations
  • Create and use a migration to manage the database
  • Create a unit test using rspec/etc
  • Create a model and basic validations
  • Handle a GET request using a Controller, Model, and View
  • Handle a POST request using a Controller, Model, and View
  • Basic HTML, CSS and JavaScript
  • Basic GIT - clone, commit, push

I wrote down some questions and answers that I have experienced from my interviews and some additional logic questions that you might find useful.

Here it is: http://anilpunjabi.tumblr.com/post/25948339235/ruby-and-rails-interview-questions-and-answers

Enjoy !!!

How to setup and deploy Rails apps to production environment

I think for the seniority level you should be able to answer most of the following questions:

Here is my blog link.

Understand ruby blocks and iterators for traversing and manipulating datasets.

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