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Development
Modern React & Next.js
by Daniel Okafor
Rated 4.9 out of 5(5,210)2 h 21 min10 lessonsIntermediate
$129$189Save 32%
Advanced
TypeScript for Professionals
Generics, narrowing and type-safe APIs without the confusion.
Rated 4.8 out of 5(2,105)15,320 students
Created by Daniel Okafor
Updated June 17, 2026Taught in English
What you'll learn
- Model domains with unions and literal types
- Write reusable generic utilities
- Validate untrusted data at runtime
- Migrate a JavaScript codebase safely
Course content
3 sections · 8 lessons · 2 h 1 min total
- Video:Structural typing explained12 min
- Video:Unions and narrowing18 min
- Video:Discriminated unions15 min
Requirements
- Comfortable with JavaScript
- Basic TypeScript syntax
Description
Move beyond 'any'. Learn the type system patterns that power real codebases, from discriminated unions to advanced generics and runtime validation with zod.
Your instructor
Staff Software Engineer
Daniel builds web platforms at scale and has shipped React in production since 2015. He loves turning intimidating topics into small, testable steps, and his code reviews are famously kind.
View profileStudent reviews
4.8
Course rating
- 5 stars: 90%
- 4 stars: 7%
- 3 stars: 2%
- 2 stars: 1%
- 1 star: 0%
- Rated 5.0 out of 5
Mateo García
Bogotá, Colombia · Aug 20, 2026
The projects make the difference. I finally understand the why, not just the how.
- PDRated 5.0 out of 5
Priyanka Das
Bangalore, India · Jun 10, 2026
I switched careers partly thanks to this course. The portfolio project got me two interviews.
- LMRated 5.0 out of 5
Lucas Moreau
Lyon, France · May 24, 2026
Thoughtful, honest teaching. No filler, just useful lessons and great examples.
- Rated 5.0 out of 5
Camila Torres
Mexico City, Mexico · Jul 13, 2026
Having it available in Spanish helped my whole team join. The certificate was a nice bonus for LinkedIn.
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