TypeScript 7 Expert

The TypeScript 7 Expert exam assesses deep knowledge of TypeScript for engineers who build libraries, tooling, and large-scale codebases — on a compiler now implemented as a native Go binary roughly 10x faster than previous versions.

Topics covered include:

• Variadic tuples, recursive conditional types, infer positions and constraints
• Branded/nominal typing patterns, F-bounded polymorphism, variance (in/out)
• Mixins, abstract constructors, decorators, declaration and augmentation authoring
• Native-port internals: deterministic checker partitioning, --checkers/--builders math, --singleThreaded scope, shared-memory model
• Deep migration mechanics: paths/tsconfig anchoring, module decision tree (nodenext/bundler/preserve), deprecation→hard-error table
• Type-level breaking changes: Unicode code-point template inference, JSDoc rework
• TypeScript 7.1 API: sync/async/fs/ast entry points, Disposable objects, snapshots, layered filesystems, content mappers
• Source phase imports: AbstractModuleSource, wasm compile/instantiate flow, import.source
• es2026/esnext lib additions in depth (getOrInsert, rawJSON, sumPrecise, allKeyed, iterator helpers)

Passing this exam demonstrates expert competency in modern TypeScript, its toolchain internals, and the TypeScript 7 ecosystem transition.