Learning advanced TypeScript: safer code step by step

If your codebase mixes quick wins with long-term risk—any creeping in, APIs hard to evolve, PRs stuck on edge cases, this workshop is for you. We'll move from “types as documentation” to “types as constraints,” refactoring a small project step by step so you can copy the patterns straight into your production code.

What attendees will learn

• Replace any with safe boundaries
• Model workflows with discriminated unions + exhaustive checks
• Add domain safety with branded types
• Design ergonomic, constrained generics without over-engineering
• Validate inputs at runtime to keep types and data in sync
• Patterns for a typed API layer

Requirements (technical & knowledge)

• Laptop with Node 20+, npm, Git, and your favourite IDE
• GitHub account (to clone the starter repo)
• Intermediate JavaScript/TypeScript familiarity (functions, modules, basic generics)

Workshop agenda

• Setup & repo tour
• Type boundaries: unknown + simple guards
• Discriminated unions & exhaustive checks
• Branded types
• Typed API layer + runtime validation
• Safer generics, recap, Q&A

Companies using this technology

Microsoft, Google, Stripe, Shopify, Airbnb, Netflix, Uber, Slack, and many others

Target audience roles

Frontend and full-stack engineers, Node.js developers, tech leads and anyone maintaining medium–large JS/TS codebases.