Mastering TypeScript: From Fundamentals to Type-Level Programming & Functional Effect-TS
Master TypeScript from the ground up to advanced type-level metaprogramming and functional architecture powered by Effect-TS. Modeled after the world-class TotalTypeScript curriculum by Matt Pocock.
(COMING SOON) Moving from object-oriented patterns to functional programming, leveraging pure algebraic data types and the immensely powerful Effect-TS ecosystem.
Use mapped types and generics to enforce finite state transitions in the compiler. A type-level state machine makes impossible states impossible to represent, eliminating entire classes of runtime bugs.
The built-in Partial and Readonly utilities are shallow. Learn how to write your own DeepReadonly and DeepPartial utilities that penetrate every layer of nested objects by combining Generics, Conditionals, infer, Mapped Types, and Recursion simultaneously.
How do you type a JSON object? A JSON object can contain arrays of objects, which can contain arrays of objects, infinitely down. You cannot hardcode this depth. You need a Recursive Type.
TypeScript provides four built-in Intrinsic utilities that manipulate the casing of string literal types at compile time. Learn how to pair them with template literals and mapped types to dynamically generate robust event handler mappings.
Template literal types allow you to use JavaScript-style template strings (${...}) inside Type Space. Learn how to generate combinations of string literals automatically via Union Permutation, and parse delimited strings (like emails or URLs) using the infer keyword.
Pattern matching with infer isn’t just for Promises and Objects. You can deconstruct Tuples and Arrays element by element in Type Space, mirroring the exact syntax of JavaScript’s array destructuring and spread operators.
An in-depth guide to intermediate TypeScript type transformations. Master generic functions and constraints (extends), indexed access types, keyof/typeof operators, built-in helpers (Pick, Omit, Record, ReturnType), and mapped type transformations.
Learn how the built-in Awaited<T> utility models the runtime await keyword. We explore how to combine the infer keyword with Recursive Type Aliases to drill down and unwrap Promises infinitely deep, and how to compose it with ReturnType for async functions.
If conditional types are the if-else statements of Type Space, the infer keyword is the variable declaration (let x = ...). Learn how to extract types dynamically via pattern matching, rebuild ReturnType, and parse Template Literal Strings at compile time.
Sometimes, you want a conditional type to evaluate an entire Union as a single monolithic entity, rather than mapping over its individual members. Learn how wrapping generic parameters in brackets [T] prevents distribution, and how to use this mechanic to build complex IsUnion checks.
