Joshua Gleitze focused on improving the reliability of Server-Sent Events (SSE) in the micronaut-projects/micronaut-core repository during June 2025. He addressed a bug where SSE endpoints did not consistently return the correct Content-Type header, ensuring all endpoints now emit text/event-stream as required. Joshua refactored the existing test suite to cover multiple SSE paths, which enhanced test coverage and reduced the risk of future regressions. His work included updates to the TextStreamBodyWriter component, aligning it with proper media type emission. He applied his expertise in API development, backend development, and testing, working primarily with Groovy and Java throughout the process.