Kotlin development services
Kotlin is the default language for Android and an increasingly good one for backend services. It removes most of Java’s boilerplate without giving up the JVM’s operational maturity.
Where we use Kotlin
Kotlin is part of the stack on these 4 services. Each page covers how we work, what you get and what it costs to start.
Kotlin in practice
Kotlin is what Java would look like if it were designed now: null-safety in the type system, data classes instead of boilerplate, coroutines for asynchronous work, and full interoperability with the Java it replaces. On Android it is not a preference — it is the platform default, and the documentation assumes it.
On the server it is quietly excellent. Spring supports it as a first-class language, and the same service typically comes out significantly shorter than its Java equivalent while keeping every operational guarantee. Because both compile to the same bytecode, adoption can be file by file rather than as a decision the whole organisation has to make at once.
What we build with Kotlin
Production Android apps built the way Google now documents the platform, with Jetpack and coroutines rather than legacy patterns.
Spring Boot services in Kotlin, where null-safety and concise data classes remove a lot of routine defensive code.
Kotlin Multiplatform for the rules that must behave identically on Android, iOS and the server.
Is Kotlin right for you?
Ask usA good fit when
- Any new Android application
- JVM backend services where Java’s boilerplate is a real cost
- Existing Java codebases that want to modernise incrementally
- Shared business logic across Android, iOS and server via Multiplatform
Probably not when
- Teams with no JVM presence at all
- Codebases where mixing two languages would add more confusion than value
- Projects whose tooling or vendors assume Java specifically
What we run alongside Kotlin
The rest of the setup, and why each piece is there. We keep this list short on purpose — every dependency is something someone has to maintain.
- Coroutines
- Asynchronous code that reads sequentially, which is what makes it reviewable.
- Jetpack Compose
- The current Android UI toolkit, designed around Kotlin.
- Ktor or Spring Boot
- Ktor for lightweight Kotlin-native services, Spring Boot for the full framework.
- kotlinx.serialization
- Serialisation without reflection, which suits both Android and the server.
- Kotest or JUnit 5
- Testing, with Kotlin-friendly assertions.
Why Kotlin
Let’s talkNull-safety in the type system
The single most common class of Android crash is a compile-time error here rather than a production incident.
Coroutines for async work
Concurrent code reads sequentially, which makes the tricky parts of a mobile app reviewable.
Interoperable with Java
An existing Java codebase can adopt Kotlin file by file, with both compiling side by side.
What we get called in to fix
Get a second opinionJava written in Kotlin syntax
Codebases converted mechanically that never adopted null-safety, data classes or coroutines — all cost, no benefit.
Null-safety defeated
Double-bang operators sprinkled to silence the compiler, which reintroduces exactly the crashes the language prevents.
Coroutine scope leaks
Work not tied to a lifecycle, continuing after a screen is gone.
Multiplatform adopted too early
Shared modules introduced before there was shared logic worth sharing, adding complexity for no return.
Kotlin or the alternative
The comparisons we are actually asked to make, answered the way we would answer them on a call.
Kotlin for new code. Java where the estate, tooling and team make switching a distraction rather than a gain.
Ktor for lightweight, Kotlin-idiomatic services. Spring Boot when you want the full ecosystem and its operational maturity.
Multiplatform when business rules genuinely must match across platforms. Separate codebases when the shared surface would be thin.
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AzureGot an idea? Let’s make it real.
Tell us the short version
This could be the first step towards a new and successful collaboration. A one-line idea and a finished spec are both fine — tell us the problem, the deadline you’re working to and what’s in your way.
Keep looking
Frequently asked questions
Yes. It is the platform default, and the current Android documentation and libraries assume it.
It can, but rarely all at once. Mixing both in one project is well supported and usually the sane route.
Where shared logic genuinely pays off. We do not push it onto projects that only ship one platform.
Yes, in the same module, compiled together. That is what makes incremental adoption realistic rather than theoretical.
On Android it is the platform default. On the server it has first-class Spring support and a stable release cadence.