kotlin

A collection of 25 posts

kotlin Featured

KotlinConf 2025 is a real bowl of fresh air for backend Devs

With their keynote that JetBrains intentionally started putting backend developers in the spotlight again. They made big, impactful announcements, both at an ecosystem and language levels and I can't wait to try out all of the new goodies.

ai Featured

My experience using Junie for the past few months

Junie is one of the best coding agent I've been trying out so far. Very well integrated with IntelliJ, great for Kotlin, and the test first focus makes it quite good at coming out with good results. However, I do miss the capability to only accept part of a solution and it can be very slowwwwww.

kotlin

Hosting Kotlin applications using Coolify

TL;DR : With Coolify you can host you Kotlin applications in seconds on your own server and benefit from auto deploys, custom domains, preview branches and more. You can see the code here, and access the sample here.

kotlin

🎉Celebrating Kotlin 2.0🎉

Upgrading a simple Kotlin and PicoCLI project to Kotlin 2.0 in under 5 minutes to celebrate the new version coming up!

kotlin

[Unit] Testing Supabase in Kotlin using Test Containers - PART 2

In this article we continue diving into TestContainers and Supabase, and run unit tests against a full local self-hosted Supabase.

supabase

[Unit] Testing Supabase in Kotlin using Test Containers

In this article, I'll dive into several methods I've been looking into to unit test a Kotlin application using Supabase and why I finally decided to go for a Docker Compose / Test Containers solution.

kotlin

My KotlinConf experience

My experience and impressions attending KotlinConf a couple weeks back. And some thoughts on the future of Kotlin.

apis

Replacing Postman with the Jetbrains HTTP Client

This blog shows a way to use the Jetbrains HTTP Client to replace Postman and test third party APIs, share requests and even run them in CI all of that within minutes!

apis

A tale of fixing a tiny OpenAPI bug

I found and fixed a tiny bug in OpenAPI, learnt about the library, jackson and git in the process. In short, get and set methods are visited by Jackson even when they aren't used anywhere in the code! Be careful how you name your methods 🔥

kotlin

Kotlin Data Classes, shallow copies and immutability

Are Kotlin data classes immutable? And does the copy method create shallow or deep copies of my class instances? Let's have a look together

elm

Easy dependency integration in Kotlin/JS using the "Elm ports" technique

Just starting with Kotlin/JS, I found it hard to use large NPM libraries like Firebase. But my past experiences with Elm and its system of ports helped me find a suitable solution. Let's dive into it!

kotlin

Tips and tricks using Hibernate and SQLite with Kotlin

This blog exposes some of the things I've found out while implementing my project. Maybe they're useful for someone else too :). Kotlin, Hibernate and SQLite doesn't seem to be a very present combination online as of now.

kotlin

Measuring time and durations in Kotlin

The DurationAPI is coming out of experimental stage, and offers a nice DSL to easily work with Time durations (duh!). If offers the obvious but also nice extra goodies like coercions and ISO/ String conversions and is notably used to calculate processing time.

kotlin

Kover : Code Coverage plugin for Kotlin

Kover is a code coverage tool for Kotlin. It's still in incubator phase but I took it for a spin and it is already very useful as part of local or CI workflows! In this article I go through the setup and some of my favourite goodies of the tool.

hacktoberfest

Automatically add the Hacktoberfest tag to all of your GitHub repositories

I created a small kotlin utility that finds all the repositories you are an owner of, and add the Hacktoberfest topic to them :) and learnt a few things

kotlin

Building Command Line Interfaces with Kotlin using picoCLI

In this article, we'll look into use cases where CLIs are a great idea. We'll also dive into best practises, and discover one of the most used library for CLIs in the JVM world : picoCLI.

adventofcode

Advent of Code Day 5 : Binary representations and data classes val inits

How I solved Advent of Code day 5, live, and what I learned from it.

adventofcode

Advent of Code Day 4 : Kotlin TIL - require, flatMapIndexed!

How I solved Advent of Code day 4, live, and what I learned from it.

kotlin

Advent of Code Day 3 : Kotlin TIL - drop, filterIndexed

How I solved Advent of Code day 3, live, and what I learned from it.

kotlin

Advent of Code Day 2 : Kotlin TIL - regex destructuring

How I solved Advent of Code day 2, live, and what I learned from it.

kotlin

Advent of Code Day 1 : Kotlin TIL

How I solved Advent of Code day 1, live, and what I learned from it.

development

Advent of Code in Kotlin : Learnings day by day.

The thread of all my solutions, day after day on how I solved Advent of Code puzzles in Kotlin! Every day I record myself, and then revisit and improve my solution to learn from them.

java

Paginate results in a command line application using picoCLI

In this article, I describe a way to paginate results in picocli applications.

kotlin

Some fun with Kotlin, Exposed and MySQL

Some lessons learned from playing around with Kotlin, Exposed, SQL and the iMDB datasets.

kotlin

Introducing Kotlin at ING, a long but rewarding story

This article describes our journey being the first team to run Kotlin in the backend at ING (Netherlands). Hopefully this article will give you some keys on how to introduce it as well in your own large company, and reduce some of the friction you might encounter.