Worked on backend development for the opentiny/tiny-engine repository, focusing on improving the reliability of the page locking workflow. Addressed a bug that caused inconsistencies in lock state by correcting the occupier update path, which previously led to stale occupier data and hindered multi-user collaboration. The solution involved switching the update mechanism to use mockService.pageService, aligning the implementation with testing fixtures and enabling more deterministic tests. This change ensured that occupier information was accurately maintained during lock and unlock operations. The work was implemented using JavaScript and backend engineering practices, emphasizing maintainability and robust multi-user support within the system.