Why Kotlin Is Gradually Taking Over the JVM

What are we seeing in 2025?

• Large enterprises like ING now have over 11% of their codebase written in Kotlin. That’s no longer marginal, that’s momentum.
• JetBrains keeps pushing new features into the language, making it even more appealing for backend engineering. (And let’s be honest: for too long Kotlin was still seen as “that Android language.”)
• Kotlin 2.2 has just been released, with improvements that may not sound exciting (“overload resolution between lambdas and suspend functions”), but that save you time and frustration. And in the end, that’s what really matters.
• AI isn’t just a buzzword anymore either. JetBrains is integrating AI features directly into Kotlin’s tooling. Whether that makes your job easier or more exciting, we’ll let you decide 😉.

What Engineers Tell Us

We talk to JVM engineers every day. The best ones want three things:

• Less boilerplate. Because no one gets joy from writing another public static void.

• More productivity and flow. A stack that feels like an upgrade, not a trip back to 2009.

• Future relevance. Let’s be real, who still wants to be “the Java 17 guy” five years from now when you could be working with Kotlin and AI instead?

And for employers, this means something concrete. If you truly want to attract the top talent in the JVM community, then Kotlin isn’t just a technical choice, it’s a recruitment advantage.

Why We Sponsor (and Why We’ll Be There)

At CodeGuild, we stand for innovation, new possibilities and the craft of software engineering.
We’re not language evangelists (well, maybe a little), but we see every day how Kotlin is connecting more engineers and companies across the JVM ecosystem.

That’s why we’re proud to support Kotlin Dev Days 2025, not to have our logo somewhere on a banner, but because we believe this event genuinely moves the community forward.

The Kotlin Event!

📅 November 27, 2025 in Amsterdam
🎤 Talks on Kotlin, AI, tooling and JVM transitions
👋 And yes, we’ll be there too. Come say hi!

A Final Note With a Wink

No, Kotlin won’t magically solve your problems. Your legacy system full of spaghetti code won’t suddenly become a Michelin-star kitchen.
But Kotlin makes an engineer’s life more enjoyable, and in a market where the best people can choose where they work, that might just be its greatest advantage.