Kotlin Dev Day 2025: the program has been announced – and why that is relevant

In the run-up to this year’s edition, the full program has been announced. It offers a clear look at the current state of the JVM ecosystem — and where Kotlin is heading next.

As a recruitment partner who speaks daily with both engineers and employers, we see firsthand how these themes play out in practice. In this article, we share what’s on the agenda and why it matters.

A Sustainable Setting: CIRCA Amsterdam

The conference takes place at CIRCA Amsterdam, a venue with an A+++ energy label, designed around reuse and efficiency. The location perfectly reflects the event’s circular spirit: giving back to the community and building a sustainable future for tech.

Wednesday: Hands-On Workshops

The day before the main event, participants can join three in-depth workshops in small groups to learn and experiment together:

• Hands-On AI Agents in Kotlin with LangChain4J & Spring-AI – build and integrate AI agents directly into your applications.

• Spring Boot with Coroutines and Virtual Threads – explore modern asynchronous patterns in server-side Kotlin.

• Pragmatic Functional Programming in Kotlin – practical insights into functional programming without heavy frameworks.

Thursday: Five Tracks of Deep Technical Content

The main conference day features five parallel tracks — Black Box, Upperdeck, Stage 3, Stage 4 and Stage 5 — each filled with 30- to 45-minute sessions. Several key themes stand out:

1. Kotlin and AI

AI is everywhere in this year’s program. Sessions such as “Building AI Agents in Kotlin with Koog” and “Supercharge your LLM with Kotlin: Model Context Protocol (MCP) in Action” show how developers are embedding language models and agents into production applications. “Can LLMs play text adventures? – Kotlin edition” takes a more playful approach, exploring the boundaries of LLM capabilities.

2. Multiplatform and Domain Modeling

Kotlin Multiplatform continues to gain traction. Talks like “Kotlin Multiplatform + Domain Models = ❤”, “Lessons Learned After Building Apps with Kotlin Multiplatform” and “Building a Modern Kotlin Multiplatform Application with Compose Multiplatform and Koin” offer practical insights into sharing domain logic across front- and back-end systems.

3. Architecture & Best Practices

A strong focus this year lies on architecture, maintainability, and framework independence. Sessions such as “Framework-Free, Future-Proof: Isolated DDD in Kotlin with (and without) Spring”, “Kotlin Clean Architecture for Serverless: Business Logic You Can Take Anywhere”, and “Beyond Data Classes: Kotlin-Powered Domain Modeling” demonstrate how developers are striving for simplicity and quality without unnecessary complexity.

4. Tooling, Productivity and the Language Itself

Beyond architecture and AI, the conference also zooms in on developer productivity and language evolution. Highlights include “43 Refactorings in 40 Minutes”, “Making Spring Boot, OpenAPI & @Transactional Play Nice with Arrow’s Either”, “Ktlint Behind the Scenes”, and a keynote on “What’s New in Kotlin: Language and Ecosystem Strategy.”

5. Community & Fun

Not everything is work. Sessions range from live-coding games such as “Snake in 10 Lines of Kotlin” to a closing roundtable with JetBrains engineers. Networking moments and social gatherings add a relaxed finish to a day of deep tech exchange.

Why This Matters for Engineers and Employers

At CodeGuild, we help developers make impactful career moves and support companies in finding the right engineering talent to drive innovation. The topics discussed at Kotlin Dev Day mirror the challenges we hear daily in our conversations:

• Scalable architectures and domain-driven design – essential for organisations building for long-term sustainability.

• AI and developer tooling – increasingly vital skills for productivity and new business models.

• Multiplatform solutions – key for teams aiming to leverage shared codebases efficiently across platforms.

Following this event helps engineers stay ahead of key developments in the Kotlin and JVM world — and helps employers understand which skills and mindsets will define the next generation of teams.

Want to Learn More?

Interested in exploring these topics further or discussing what they mean for your team or career?
Visit our dedicated Kotlin page, where we bring together all relevant articles and insights — including this one. It’s how we give a platform to craftsmanship and knowledge, without taking the stage ourselves.

Kotlin Dev Day 2025 promises to be not only rich in content, but also a celebration of community and professional mastery. We look forward to seeing you there.