New thinking tools.

It's time to learn Kotlin, a mega-powerful language with open doors to different platforms: desktop, mobile, web, and even all at once in the same project.

I made this course to give you essential Kotlin programming skills that will quickly get you active in any Kotlin project. You'll get solid practice in Kotlin's fundamentals, and syntax is the smallest part. With 100+ practical examples and exercises inspired from real-life experience, you'll not only get the foundations right but some 2500+ lines of code under your belt.

And code is one thing, but this course has a deeper purpose: to teach you to think differently.

As we progress through the course, you'll see that your mental model will start to change, and you'll write more compact and powerful code, faster. By the end of the course, you'll have your first application ready to build, deploy and ship, and I use it on my own pictures, on camera.

What is Kotlin?

Kotlin is a language designed to make programming simpler, faster, and way more fun - clean, concise code that's a breeze to read and write, leaving behind the headaches of verbose syntax or obscure primitives.

It's a game-changer.

With Kotlin, you can create apps for Android, applications for the web, for the server-side, or multiplatform with shared code. You rarely get a more powerful combo. Kotlin also plays nice with Java and the massive JVM ecosystem, so you have access to a giant amount of battle-tested code for your projects.

But the real kicker is this: Kotlin gives you a mental framework that works well in just about any environment, whether you're using low-level code for hyper-optimizations, or high-level code and functional programming for fast productivity.

How This Course Works

Who is this course for?

Software engineers or students with some experience with at least another programming language. The language is not really important - what matters in this course is the mental model, and I'll draw many similarities and differences with other programming langauges, including Java, Scala, the C family, Python, JavaScript, and others.

If this is the first time you're learning to code, you should do just fine in this course, but the pace might be a bit quick because I don't cover the general computer science fundamentals.

Really, anyone looking to learn Kotlin hands-on is welcome in this course, and you'll get a solid 2500 lines of code in this course and your first Kotlin JVM application ready to use, among a hundred other examples and exercises.

Not sure if it's for you? Money back if it's not a fit πŸ’°

This screenshot shows you the code that we'll write together.

Platform Agnostic

Many people learn Kotlin to build Android apps. This course does not focus on Android, but on Kotlin as a general programming language.

Hear me out 😲

With the skills you learn in this course, you'll be able to build not just Android apps, but server-side applications, web applications (frontend and backend), and multiplatform projects. As you can see, this course transcends any platform!

If you're exclusively focused on writing Android apps and learning Kotlin only as a side objective, this course may not be for you - but beware! Not knowing Kotlin well is going to cause problems later, because at some point, you'll need to know why some things work the way they do in Kotlin.

Regardless of what your goal is, this Kotlin course - as its name suggests - is essential.

100% Practical

Long story short: code is king, and we write it from scratch. We don't waste time on endless theory, and I only use 1-2 slides every lesson as "flashcards" you can come back to.

Besides the 100+ examples and exercises, we also write a mini-project in the course: a command-line image processor, which is able to crop, grayscale and apply a bunch of filters, like blurring, sharpening, or blending, like in this example I made for when my grandkids look at me through their 7D-Virt-Spatz lenses.

In the process, you'll get hands-on experience not only with Kotlin-specific features, but good coding & organizational practice in general.

Skills You'll Learn

After this course, you'll be able to:

βœ“ understand Kotlin in production environments and in most projects

βœ“ start contributing to Kotlin projects in minutes instead of days

βœ“ write applications for any target, including Android, server, web and multiplatform

βœ“ learn advanced Kotlin tools and libraries very quickly

βœ“ write more reliable and compact code, faster

Skills you'll get:

  • Lasting comfort with the Kotlin language
  • syntax (of course, LOL)
  • types and type inference
  • expressions vs instructions
  • control structures and how they differ from other languages
  • string templating
  • Extended object-oriented concepts
  • classes, instances, constructors, properties, methods, the usual
  • nullables
  • new method notations for expressive code
  • extension methods
  • operator overloading
  • the singleton pattern in one line of code
  • inheritance
  • abstract classes and interfaces
  • generics
  • exception handling
  • delegation
  • anonymous classes
  • value classes
  • enums
  • Functional programming
  • using functions as values
  • anonymous functions (lambdas)
  • higher-order functions
  • collections and their "standard" and functional APIs
  • single-abstract-method patterns (SAM)

and much more, all with live runnable examples and practiced with exercises.

Besides these, maybe some image processing fundamentals you may not have known about πŸŽ‡ because you are going to write them! 🀯

Plus some extra perks:

  • You'll have access to the entire code I write on camera (2500+ LOC)
  • You'll be invited to our private Slack room where I'll share latest updates, discounts, talks, conferences, and recruitment opportunities
  • You'll have access to the takeaway slides

Meet Rock the JVM


I'm a software engineer and the founder of Rock the JVM.

I worked on my first production Kotlin server-side application in 2017 (when Kotlin server-side wasn't cool yet πŸ˜†), a logistics management application for a big plane manufacturer. I've written a lot more code since, I learned a ton, and I want to share everything.

As of February 2024, I've taught Kotlin, Scala and other libraries to 100000+ students at various levels and I've held live training sessions for some of the top companies in the industry, including Adobe and Apple. I've also taught university students who now work at Google and Facebook (among others), I've held Hour of Code for 7-year-olds and I've taught more than 35000 kids to code (not in Kotlin, yet πŸ˜†).

You're in good hands in this course. I'll guide you every step of the way, and our private community at Rock the JVM is full of passionate people just like you.

With Special Thanks To

Riccardo Cardin, one of the best Rock the JVM alumni, now a senior software engineer and an important contributor on the Rock the JVM blog, focusing on high-performance systems in Scala, Kotlin and Java. Big thanks, Riccardo, for reviewing the code I prepared for this course.

kjpargeter on Freepik for the free background I used for photoshopping the banner of the course.

What's Included

πŸ“Ή 13.5 hours of 4K content

πŸ‘©β€πŸ’» 2500+ lines of code written

πŸ‹οΈ 100+ examples and exercises

🏞️ 1 image processor app written & exported

🀯 1 mind blown away - hopefully yours!

  Kotlin Foundations
Available in days
days after you enroll
  Object-Oriented Programming in Kotlin
Available in days
days after you enroll
  Object-Oriented Kotlin Features
Available in days
days after you enroll
  Functional Programming in Kotlin
Available in days
days after you enroll
  Operational Kotlin
Available in days
days after you enroll
Available in days
days after you enroll

Take this course now!

100% Money Back Guarantee

If you're not happy with this course, I want you to have your money back. If that happens, email me atΒ [email protected]Β with a copy of your welcome email and I will refund you the course.

Less than 0.05% of students refunded a course on the entire site, and every payment was returned in less than 72 hours.


1. Does this course cover Android?

Nope - this course is 100% focused on Kotlin as a programming language, without caring which platform you're going to write code for.

2. How is a typical lesson like?

We generally create separate mini-applications where we'll explore a certain feature of the Kotlin language, with examples and exercises. Each lesson is about 10-20 mins long.

We also have a mini-project: a command-line image processor, which can resize images and perform various effects (grayscale, blend modes, blurring, edge detection).

3. Is this Kotlin course hard?

Not really. If you have some existing experience coding in another language, this course should be relaxing enough to have fun, but will give you a nice brain stretch.

If you haven't programmed before, the course might be a bit tougher, simply because we skip the CS fundamentals. But don't stress about it! Ask in our private community if you ever get stuck, and we'll help.

4. Do you give a certificate?

Sure do! You'll automatically get a certificate which you can export and use this to get reimbursed or land your Kotlin job.

5. Can I expense this at my company?

Of course! After you enroll, you'll automatically get a tax-compliant receipt which you can use to reimburse this course with your employer.

6. I'm an advanced Kotlin user. Should I take this course?

Probably not. The advanced course might be better for you.

7. What if I don't like the course?

Money back, easy πŸ’° Only a handful of people ever asked for a refund on the entire site of 20+ courses, just to give you an idea.

8. Do you have any connection to JetBrains or the Kotlin Foundation?

Nope - this course is not affiliated with JetBrains (the creators of Kotlin), Google or the Kotlin Foundation. I hope they say good things about this course once they see it, though!