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Most books teach TypeScript as a list of features. This one teaches it as a place.

The City of Types begins in the undefined void, before the first value has a name, and builds outward: primitives become atoms, operators become machines, control flow becomes roads, and types become the laws that decide what can and cannot exist. Chapter by chapter you do not memorise the language. You watch it grow, and you learn to think in it.

Thirty chapters, each ending in a hands-on kata where the city breaks and you repair it. By the last page you will stop asking whether code works and start asking whether it can ever be wrong.

For developers who know some JavaScript and want to understand TypeScript from the ground up, not from the reference manual.

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Kick off your book project, get started with GhostAI, get better at marketing, or spend the day doing all three! Free live workshops on Zoom. Saturday, June 27, 2026.

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