During April 2025, Chen Jiazi developed API-based speed limit configuration features for the PeerBanHelper repository, enabling users to manage bandwidth for BitTorrent clients such as qBittorrent and Deluge. Leveraging Java for backend development and integrating with external APIs using JSON and YAML, Chen implemented endpoints to get and set both primary and alternative speed limits. The solution included robust error handling and mapped user requests to internal configuration interfaces, enhancing reliability. This work improved bandwidth control and reduced network contention for end users, while establishing a scalable pattern for future client integrations within the configuration management domain.