Where Developers Level Up

Deep technical content for developers who want to master their craft.

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Software Design

Messages Before Objects

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Software Design

Singleton Pattern

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Software Design

The Cost of Change in Software

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Software Design

Dependency Inversion Principle

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Software Design

Interface Segregation Principle

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Software Design

Liskov Substitution Principle

A graphic illustration of the SOLID Open-Close Principle, featuring metallic text and a golden gear icon with an open door, set against a blueprint background with code snippets.

Software Design

Open-Closed Principle

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Software Design

Value Objects in Ruby: The Idiomatic Way

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Software Design

Single Responsibility Principle

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The N+1 Query Problem in Active Record

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Testing in Ruby: From Scratch to Minitest and RSpec

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Sinatra Tutorial: Building a To-Do Application

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Build Your Own URL Shortener with Rack

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Persistent Connections in Ruby: Streaming Bodies, SSE, and WebSockets with Rack

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Rack for Ruby: The Complete Beginner’s Guide

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ERB: Embedding Ruby in HTML

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Using Ruby Libraries

Broken ruby

Do Not Use the System Ruby on macOS

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Install Ruby: A Step-By-Step Guide

Installing and Using Tailwind CSS 4.0

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How to Implement a Cookie Bar in Ruby on Rails

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Seeding a Database in Ruby on Rails