Design patterns

Once by the book.
Once in production.

A pattern as the literature describes it, then the shape it takes in a real system. See what changes, why it changes, and when to reach for it — from creating a value to coordinating a set of collaborators.

Starting with TypeScript, Go, and Python Go is the default comparison. Python is also available.
30 articles

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Creation and lifecycle

Making things, keeping them valid, and deciding how long they live.

Composition and interfaces

What wraps what, and where one interface meets another.

Behavior and collaboration

Who talks to whom, who makes the decision, and who owns the work.

Application patterns

Reusable arrangements at the seams of an application.