During November 2025, Tibtof enhanced error handling in the Arrow Kotlin library by developing new overloads for the zipOrAccumulate function within the arrow-kt/arrow repository. This work focused on enabling more robust error accumulation across multiple actions, allowing developers to compose multi-step pipelines that handle errors more flexibly. Tibtof applied functional programming principles and Kotlin expertise to design an API that supports complex error-prone operations, improving the library’s composability. The feature was developed collaboratively, with contributions from Copilot and Alejandro, and demonstrates a thoughtful approach to extending error handling capabilities without introducing unnecessary complexity or breaking existing functionality.