---
title: "Companion Extensions"
description: "1 posts about Companion Extensions, summarised, each linking to the original."
---

# Companion Extensions
> 1 posts about Companion Extensions, summarised, each linking to the original.

## Articles

### [The Companions to Come](https://yomu.fyi/post/the-companions-to-come.md)
- Company: [Jetbrains](https://yomu.fyi/company/jetbrains.md)
- Author: Daria Voronina
- Published: Sep 30, 2026
- Type: Announcement

JetBrains is extending Kotlin’s companion mechanism with experimental companion blocks and companion extensions in Kotlin 2.5.0. Companion blocks replace the object keyword with a companion block, compiling members as static members on the JVM. Companion extensions allow adding class-level members to any type, even types the developer does not control. These features improve multiplatform interoperability by enabling expected companion block members to be actualized using Java static members. Companion objects remain fully supported and are still required when the companion must implement an interface, but companion blocks are recommended for new code.