Video Courses

Expert-led video courses covering legacy code modernization strategies and essential design patterns.

Legacy Code Modernization

Master proven strategies for safely modernizing legacy systems without breaking production.

Legacy Code Modernization: How to Migrate Without Breaking Production

An overview of legacy systems, why they persist, and strategies for modernizing them.

Strangler Fig Pattern: Migrate Legacy Systems Without Downtime

A comprehensive guide to safely modernizing legacy systems using the Strangler Fig Pattern.

Branch by Abstraction: Swap Dependencies in Production Without Downtime

Learn how to safely swap dependencies in production without breaking anything.

Parallel Run Pattern: How to Deploy Rewrites Without Breaking Production

Run old and new implementations side-by-side to validate correctness before switching over.

Feature Flags: Deploy Safely & Release Confidently in Legacy Systems

Master gradual rollouts, safe deployments, and risk-free releases using feature flags.

How to Test Legacy Code With Zero Tests

Learn proven techniques to safely add tests to untested legacy code and enable confident refactoring.

Seams: How to Test Legacy Code Without Breaking Production

Learn Michael Feathers' concept of seams for testing legacy code without breaking production.

Database Migration Strategies: Zero-Downtime Deployments for Production Systems

Master zero-downtime database migrations using expand-contract, dual writes, and backward-compatible schema changes.

Design Patterns Explained

Learn essential design patterns with clear examples and practical applications for legacy code.

Decorator Pattern Explained: Stop Class Explosion with This Simple Technique

Learn the Decorator design pattern for adding behavior to objects dynamically without inheritance.

Observer Pattern Explained: Stop Writing Tightly Coupled Code

Understand the Observer design pattern for building event-driven systems and reactive applications.

Singleton Pattern Explained: When to Use It (and When NOT To)

Master the Singleton design pattern - when to use it, when to avoid it, and why it's controversial.

Factory Pattern Explained: Stop Using 'new' Everywhere

Learn the Factory design pattern for creating objects without tight coupling to concrete classes.