TypeScript Mastery
Go from JavaScript to production-grade TypeScript. Covers type system fundamentals, generics, decorators, strict mode, advanced utility types, and integrating TypeScript in real-world projects.
Oleksii Anzhiiak
Software Architect, Senior .NET Engineer & Co-Founder
By the end you'll be able to
- Add types to JavaScript code without breaking it
- Read and write production TypeScript — generics, conditional types, mapped types
- Catch entire categories of bugs at compile time instead of in production
- Configure tsconfig and the type checker like a senior would
- Make a JS-to-TS migration path for an existing codebase
Is this course for you?
This is right for you if you…
- You write JavaScript daily and the team is moving to TS — you want to be a contributor in that move, not a blocker
- You're aiming at any frontend role above junior — TS is now the default in 2026, not the upgrade
- You want type safety on a Node backend you're shipping
Don't take this course if you…
- You don't know JavaScript yet — TypeScript is JavaScript plus types; the JS half can't be skipped. Start with #11
- You want to learn another statically-typed language — try the C# course (#1) or Go elsewhere. TS is JS-shaped on purpose
- You hate types — there are ecosystems where dynamic typing wins (Python data science, scripts). This isn't your course
Who teaches this
Oleksii Anzhiiak
Software Architect, Senior .NET Engineer & Co-Founder
Oleksii Anzhiiak is a Software Architect, Senior .NET Engineer, and Co-Founder of ToyCRM.com and ProfectusLab. With over 15 years of experience, he specializes in distributed systems, cloud infrastructure, high-load backend development, and identity platforms. Oleksii designs complex architectures, builds secure authentication systems, and develops modern engineering education programs that help students achieve real career results.
Currently leads architecture for ToyCRM.com — a multi-tenant CRM platform built on .NET by our team. The same patterns and design decisions used there appear directly in the courses: identity & auth, distributed services, code review culture. You learn from engineers actively shipping production code, not from a textbook.
Syllabus
This course upgrades your JavaScript to TypeScript in six focused modules:
- 1 Module 1: Type system basics — primitive types, type inference, union & intersection
- 2 Module 2: Interfaces and type aliases — extending, merging, readonly, optional
- 3 Module 3: Generics — generic functions, classes, constraints, utility types
- 4 Module 4: Advanced types — mapped types, conditional types, template literals, infer
- 5 Module 5: Decorators and metadata — class, method, parameter decorators, reflect-metadata
- 6 Module 6: Real-world projects — tsconfig mastery, integrating with React/Node.js, type-safe APIs
Prerequisites
JavaScript ES6+ knowledge required.
Solid JavaScript knowledge required. Familiarity with ES6+ features (modules, classes, async/await).
What you'll build
You leave able to take a JavaScript project and bring it to type-safe TypeScript without rewriting it. The skill that turns 'I write code that works' into 'I write code that other engineers trust'.
- Static types vs dynamic types — when each helps
- Generics, conditional types, mapped types
- Strict mode and tsconfig settings that matter
- Type narrowing and discriminated unions
- Type-safe API contracts and DTOs
Where this fits in your career
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First lesson on us. Decide after meeting your instructor.
Sit in on the first session. If after lesson 1 you decide the instructor isn't the right fit, you don't pay for it — and no awkward conversation. (Trial offer applies to courses with more than 5 lessons; this one qualifies.)
Pricing & what's included
What's included
- 12 live sessions × 2 hours each — taught by the instructor, not a recording playback
- Slide deck for every session — yours to keep and refer back to
- Working code files and any data files used in class — cloned to your machine
- Weekly homework with personal code review from the instructor
- Recording on request — give the teacher a heads-up ("can't make Tuesday, please record it") and the session is recorded for you
Frequently asked questions
How much time per week will this take?
Plan for the live sessions plus roughly 1.5–2 hours of practice per session. Most students who finish on schedule put in 4–6 hours a week total. If you put in less, you still finish — it just takes longer.
What if I miss a class?
Tell the teacher BEFORE the session — "I can't make Tuesday, please record it" — and the teacher records that lesson and sends it to you. Recordings aren't a default catch-up archive; they're produced on request when you give a heads-up. After the lesson you do the homework, bring questions to the next session.
What's included in the price?
Live sessions with the teacher; the slide deck for each session (yours to keep); the working code files and any data files used in class; weekly homework with code review; and recordings of the sessions you give advance notice for. Anything beyond that — a certificate, alumni access, mock interviews — is listed explicitly in "What's included" above the FAQ for the courses where it applies.
What if I sign up and the teacher isn't a fit?
For courses with more than 5 lessons, the first session is effectively a trial — if after lesson 1 you decide the teacher isn't a fit, you don't pay for it. We'd rather you walk away after one lesson than push through 9 weeks of bad chemistry. (Courses with 5 or fewer lessons are short enough that the standard pricing applies — the trial offer doesn't make sense at that length.)
Can I get a refund partway through?
Yes. Within 14 calendar days of purchase you can withdraw and get a full refund on request, no reason needed — that's your statutory right under Georgian consumer-protection law. On top of that, our own guarantee: if you've attended fewer than 3 lessons, we refund in full with no deductions. Refunds go back to your original payment method within 14 days.
Can I switch the language of instruction?
The live sessions run in the language listed under "Available Languages" above. Slides and code files are typically available in all four (English, Russian, Ukrainian, Georgian). Many students attend sessions in one language and read materials in another — that's normal.
Will I be ready for a real job after this course?
One course rarely gets anyone hired by itself — for any field. What this course gives you is the foundation a junior hiring manager expects: working code you wrote yourself, the vocabulary to read other people's code, and the practice habits that make you employable. The honest answer to "am I ready?" is on our roadmap (link in the page header) — open the level you want to reach and read the "You're ready when" checklist.
Can I pay in instalments?
Yes for courses with a "Monthly Payment" option in the at-a-glance ribbon — usually two or three equal monthly payments. Courses without that option are paid in one go. If the price is the blocker, write to us — we look at every case.