typescript-expert-2025

Expert TypeScript development patterns and tooling for December 2025. Use when (1) Setting up modern TypeScript projects with Bun, Node 22+, or Deno, (2) Configuring tsconfig, ESM/CJS dual publishing, or build tooling, (3) Implementing advanced type patterns like satisfies, as const, template literals, mapped types, (4) Choosing between Biome, Oxlint, or ESLint for linting, (5) Optimizing TypeScript performance, or any expert-level TypeScript architecture questions.