Become a Scala wizard. Learn how to manipulate Scala code at compile time (with Scala!) and write powerful code and tools that other developers only dream about.
As you already know by now, Scala is the most powerful programming languages on the JVM and one of the most powerful programming languages, period. For more than 20 years, Scala has been an inspiration for other languages, starting with Java and Kotlin.
Here’s something that the other languages will never be able to match any time soon: the ability to generate, analyze, transform and manipulate code, at compile time, with the same language.
In Scala, this is possible. You can manipulate other Scala code at compile time, with Scala as the tool to do it. With this power, you can create libraries, tools and functionality that other developers can only dream about. Only a few people besides the Scala compiler team know these techniques.
This is what you’ll learn in this course.
Few languages offer true metaprogramming, i.e. the ability to manipulate code as it’s being evaluated or compiled. Lisp (with its family) is the gold standard, because it’s easy to represent code as data. The dynamic type system also helps, because there is no requirement for how code should look like: it’s just a list like anything else! So how do you use it, and how can you make sure that the code you get is correct? Oh yes, you can’t.
Scala is different.
For the first time in a statically-typed language, Scala gives us the power to manipulate code at compile-time, with all the types in place, with all the regular data structures we normally use, with even more powerful pattern-matching, with the guarantee that either the code is correctly specified, or it doesn’t compile. It’s magic.
With these techniques, you can create:
and much more.
This course is for the seasoned Scala developer. You’re probably a senior developer, a Scala expert in your team, a lead who sets the standard, a library or tooling developer, or all the above.
If you need to write:
or just want to know the most powerful and rare Scala skills, this course is for you.
We write about 2600 lines of code from scratch in the course - very likely the most powerful Scala you’ve ever written so far. This picture shows you what we’ll do in the course.
You know the style of Rock the JVM: we learn best by writing code.
We do have slides, but only after we write the code. It’s mostly “flash cards” that you can refer back to after you finish the course.
There’s no substitute for hands-on practice, and in this course we have plenty of examples. This course is tough, but you’ll come out of it as one of the few people that know metaprogramming in Scala with macros.
We also have two real-life projects in the course that we’ll write from scratch, we’ll talk about them in a bit.
More than the code, though, this course will expand your mind on what’s possible in a programming language. You’ll learn about the compilation process, about what a programming language can and can’t do, and you’ll get timeless skills that you can transfer to other languages. It will be easy, since Scala has been an inspiration for other languages for decades.
If you need just a one sentence to convince you: if this course doesn’t prove to you that Scala is THE most powerful programming language you’ve ever seen, nothing will.
This is a tool we write from scratch, which is a 2-in-1: it fixes bad code, and makes okay code good.
Here’s an example. A combination of "My string" + aValue is generally considered bad practice, even though not enforced by the language. The Wartimizer is able to detect instances of this smell in your code and signal a compile error in the right place.
Another example. Juniors may not know all the standard libraries, so they may write things like aList.filter(somePredicate).headOption, where a .find(somePredicate) will do. The Wartimizer detects it, and automatically replaces the calls at compile time, without any intervention from you.
You’ll design Wartimizer so that you can add as many wart removers (signal bad code) or optimizers (improve okay code) as you want, or apply them selectively on a piece of code.
This is a tool that will “talk” to a database, figure out table structures, and synthesize correct types for your data, at compile time.
Normally, we need ORM libraries or magical stuff like Doobie or Quill to be able to map database types to our data model that we write manually. This project is an experiment: what if we skipped all that and synthesized types automatically with the right fields before the code is even compiled?
This is the most black-magical examples in this course. If you finish this project, you’ll be able to build any library or tool in Scala, period.
I'm a software engineer and the founder of Rock the JVM.
I'm a software engineer and the founder of Rock the JVM. I started the Rock the JVM project out of love for Scala and the technologies it powers - they are all amazing tools and I want to share as much of my experience with them as I can.
As of February 2024, I've taught Java, Scala, Kotlin and related tech (e.g. Cats, ZIO, Spark) to 100000+ students at various levels and I've held live training sessions for some of the best 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.
I have a Master's Degree in Computer Science and I wrote my Bachelor and Master thesis on Quantum Computation. Before starting to learn programming, I won medals at international Physics competitions.
Daniel is a Scala developer and a frequent speaker at Scala conferences. He describes himself as a somewhat functional developer who is convinced that the best way to learn something is to teach it.
Just the course with a one-time payment
All of the Rock the JVM courses
Become a Scala and functional programming expert from scratch with our all-inclusive course bundle: master everything you need in one complete package, at a discount
If you're not happy with this course, I want you to have your money back. If that happens, contact me 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.
This site uses cookies. Check our cookie policy (TLDR: no personal information is stored). For more information see our cookie policy.