Koyo worked on the eth-brownie/brownie repository, focusing on restoring the Sepolia-ETH API endpoint’s functionality by updating its path to include the required /api suffix. This change addressed a critical bug that had disrupted testnet operations and external integrations. Koyo’s approach involved careful API debugging and strict adherence to API specifications, ensuring compatibility and preventing downstream failures. The solution was co-authored with another developer, reflecting effective cross-team collaboration and change management. Utilizing skills in API development and configuration management, and working with Markdown and YAML, Koyo’s contribution improved reliability and maintained a stable developer experience for Brownie users.