Java works. It’s stable, well-supported, and powers a massive amount of backend infrastructure across the world. I’ve written Java professionally for decades, and I’ve built systems with it that I’m still proud of.

But after years in the language, I started to feel like I was spending more time managing code than writing it.

Less Ceremony, More Signal Link to heading

Java’s verbosity isn’t just about lines of code — it’s about all the overhead that surrounds even simple tasks. Defining a new class means:

  • Creating a nested directory structure to match the package
  • Declaring a package, writing a constructor, creating fields
  • Generating getters, setters, equals(), hashCode(), and maybe toString()

Kotlin simplifies all of this:

  • You can define multiple classes in a single file, which is great for grouping related domain objects or components
  • Constructors are compact and expressive, often written inline with the class header
  • Data classes give you a fully functioning POJO with one line of code

Instead of wiring together boilerplate, I’m able to focus on the logic that matters.

Readability Through Simplicity Link to heading

Kotlin often lets me express the same idea in half the code, without sacrificing clarity. It’s not about clever tricks — it’s about defaults that make sense and reduce mental overhead:

  • Type inference means I don’t have to repeat myself
  • Extension functions let me write expressive, readable utility code
  • The overall syntax encourages clean, linear thinking

I still care deeply about readability — but Kotlin helps me write code that’s both concise and clear.

Null Safety That Works Link to heading

In Java, null safety is about convention, discipline, and a handful of annotations. In Kotlin, it’s baked into the type system. The compiler makes it hard to accidentally dereference null — and easy to express safe defaults and fallback logic.

It doesn’t eliminate all bugs, but it eliminates an entire category of bugs. And in backend systems, that’s a big deal.

No Library Lock-In Link to heading

Kotlin is fully interoperable with Java, so I can use every existing Java library without friction. That includes Spring Boot, Reactor, Jackson, and anything else I’ve depended on over the years.

This made the transition smooth: I started with one module, evaluated how it worked, and slowly adopted Kotlin more broadly — no rewrites required.

Java Upgrades are a Production Project Link to heading

One of the less-discussed benefits of Kotlin is that it moves faster than Java — and it moves independently of your JDK version.

Upgrading Java in a large system isn’t trivial. It touches:

  • Developer machines
  • Build servers
  • CI/CD environments
  • Deployment infrastructure

It can take weeks or even months to upgrade Java safely across all systems. With Kotlin, I can adopt new language features incrementally without needing to upgrade the underlying JDK at the same time.

Why Kotlin? Link to heading

Kotlin didn’t win me over because it was trendy. It won me over because it solved problems I’d been living with for years — and it did so in a way that felt practical, mature, and well thought-out.

It makes backend development faster, cleaner, and safer — and once I started using it, I had a hard time going back.