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. Chen implemented Java backend endpoints to get and set both primary and alternative speed limits, integrating with external client APIs and mapping user preferences to internal configuration interfaces. The work included robust error handling and clear messaging, enhancing resilience and user experience. By leveraging skills in API integration, backend development, and configuration management, Chen’s contributions improved bandwidth control, reduced network contention, and established a scalable pattern for future client integrations.