High-level policy vs. low-level policy. Declarative vs. imperative. Specification vs. implementation. Abstraction vs. concretion. BDD vs. TDD. Driving design based on behavior vs. focusing on implementation details. What are we talking about here? There's a philosophical idea about software design underpinning all of these discussions. The idea is that software design should be contractual. That is, we succeed when we use contracts — when we decide what we should build, and can describe it clearly — before we build…

Howdy 👋

This is an online wiki and book about the basics of software design and architecture with TypeScript by Khalil Stemmler, Developer Advocate @ Apollo GraphQL .

This book’s mission is to teach developers the essential skills and practices to write testable, flexible, and maintainable code.

You can read more about the learning journey in the "Software Design and Architecture Roadmap 🖼️".

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