1. How to use this path
TypeScript · 44 pages source format
TypeScript is JavaScript plus static types — compiles away to JS. Complete the JavaScript path first (or equivalent). This path moves from strict setup through types and unions to generics, utility types, and migration. Types should help you, not fight you.
What you'll learn
- Prerequisites and pace
- When types pay rent vs when to skip
- Migration mindset
Prerequisites
Comfortable with JS: functions, objects, arrays, async/await, ES modules. If not, finish JavaScript Checkpoint A first.
Do this now
Self-check: can you write a fetch + render app in vanilla JS modules? If no, pause and complete that.
Study pace
Plan 4–8 weeks at 6–10 hrs/week after JS fluency. Weeks 1–2: strict, types, unions. Weeks 3–4: generics, utilities, API typing. Weeks 5–6: migration + Checkpoint B.
- Recommended: 6 weeks at ~8 hrs/week
- Accelerated: 4 weeks at 2 hrs/day
- Slow track: 8 weeks alongside other work
Do this now
Add a ts-journey folder or branch in your existing JS repo. You will migrate it incrementally.
Rules of the road
strict: true always. Prefer inference — annotate when compiler cannot or when API clarity helps. never use any unless escaping hatch with comment. Read errors — they teach.
Do this now
Read Checkpoint A and B criteria now. Note in README.
Pro tip. TypeScript errors are suggestions, not insults. Hover in VS Code for plain-English hints.