During June 2026, contributed to the esl/MongooseIM repository by developing a domain-wide message broadcasting feature that enables administrators to send messages to all users within a domain through a GraphQL API. The backend was extended to support RDBMS-based user management, with particular attention to cross-database compatibility for CockroachDB and MySQL. Reliability was enhanced by improving worker lifecycle management, ensuring robust resume and restart behavior across multi-node deployments. Comprehensive instrumentation and expanded test coverage were introduced using Erlang, focusing on dynamic domains and large-scale scenarios. These efforts improved operational resilience, observability, and deployment confidence without introducing new bugs during the period.