---
title: "Kotlin Meetup: Contract-Based Testing & Kotlin Contracts — 4 Nov · FDE Amsterdam"
description: "Wed 4 Nov, 17:30 · Amsterdam · by NLKUG - Dutch Kotlin User Group. Hello, Kotlin enthusiasts! 👋 Join the Dutch Kotlin User Group on Wednesday, 4 November…"
canonical_url: "https://fde.amsterdam/events/kotlin-meetup-contract-based-testing-and-kotlin-contract-2026-11-04"
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  "og:title": "Kotlin Meetup: Contract-Based Testing & Kotlin Contracts — 4 Nov · FDE Amsterdam"
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> Index of every page on this site: [llms.txt](https://fde.amsterdam/llms.txt)

# Kotlin Meetup: Contract-Based Testing & Kotlin Contracts

by [NLKUG - Dutch Kotlin User Group](https://fde.amsterdam/communities/nlkug-dutch-kotlin-user-group)

## About this event

Hello, Kotlin enthusiasts! 👋

Join the Dutch Kotlin User Group on Wednesday, 4 November 2026, for an evening exploring contracts from two perspectives: building reliable integrations and understanding the analyses Kotlin’s compiler performs for you.

Willem Veelenturf and Jerre van Veluw from Flock will demonstrate contract-based integration testing with Kotest and Wirespec. Then Alejandro Serrano Mena from JetBrains will explore Kotlin contracts and how they are evolving into new language features.

Meet fellow Kotlin developers, exchange ideas, and join the discussion. Make sure to RSVP!

📍 Location: Xebia Netherlands - Amsterdam - Wibautstraat

🕣 Timeline

[Full details on Meetup ↗](https://www.meetup.com/dutch-kotlin-user-group/events/316996254/)

## Topics

[Platform & DevOps](https://fde.amsterdam/events/topics/platform-devops)

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## Sitemap

See the full [sitemap](https://fde.amsterdam/sitemap.md) for all pages.