Ruby

roadmap.sh: https://roadmap.sh/ruby

Suggested path through the Ruby nodes. Each node links to its lesson when written.

Nodes

Getting started

• What is Ruby?
• History and philosophy (MINASWAN)
• Installing Ruby (rbenv, rvm, asdf)
• IRB and the REPL
• Running scripts
• Ruby versions and implementations (MRI, JRuby, TruffleRuby)

Language basics

• Everything is an object
• Variables and scope
• Data types (Integer, Float, String, Symbol)
• Booleans, nil, and truthiness
• Strings and interpolation
• Symbols vs strings
• Arrays
• Hashes
• Ranges
• Operators
• Comments and documentation

Control flow

• if / unless
• case / when (and pattern matching)
• Loops (while, until, for)
• Iterators (each, map, select, reduce)
• Ternary and conditional modifiers
• break, next, redo

Methods and blocks

• Defining methods
• Arguments (default, keyword, splat, block)
• Return values
• Blocks
• Procs and lambdas
• yield
• Method visibility (public, private, protected)

Object-oriented Ruby

• Classes and objects
• Instance variables and methods
• Class variables and methods
• attr_accessor / reader / writer
• Inheritance
• Modules and mixins
• include vs extend vs prepend
• Comparable and Enumerable
• Polymorphism and duck typing
• Constants
• self
• Method missing and respond_to?

Metaprogramming

• Open classes (monkey patching)
• define_method
• send and public_send
• instance_eval / class_eval
• Reflection (methods, instance_variables)
• Hooks (included, inherited, method_added)

Error handling

• begin / rescue / ensure
• raise
• Exception hierarchy
• Custom exceptions
• retry

Standard library and core

• Enumerable module
• Comparable module
• Struct and OpenStruct
• Time and Date
• File and IO
• JSON
• Regular expressions
• Set

Functional features

• Higher-order methods
• Method chaining
• Lazy enumerators
• Frozen objects and immutability

Tooling and ecosystem

• Gems and RubyGems
• Bundler and the Gemfile
• Creating a gem
• Rake tasks
• IRB / Pry for debugging
• RuboCop (linting)
• Documentation with RDoc / YARD

Testing

• Minitest
• RSpec
• Test-driven development
• Mocks and stubs
• Fixtures and factories

Concurrency

• Threads
• The GVL/GIL
• Fibers
• Ractors
• Async and non-blocking IO

Beyond the language

• Ruby on Rails (web framework)
• Sinatra (microframework)
• Building CLI tools
• Garbage collection and memory
• Performance profiling and benchmarking

Resources

See resources.md.

Project ideas

• Build a command-line tool (e.g. a Markdown-to-HTML converter or a budget tracker) packaged as a gem with Bundler, Rake tasks, and RSpec tests.
• Write a small web framework or app with Sinatra to understand routing, middleware, and Rack before reaching for Rails.
• Implement a classic algorithm library (sorting, graph traversal) leaning on Enumerable, blocks, and metaprogramming, fully tested with Minitest.