Worked on performance optimization for the nim-lang/Nim repository, focusing on the JavaScript backend. Developed a feature that enables NimCopy cursor inference, allowing the compiler to elide unnecessary deep copies for value aliases. This involved updating the JavaScript code generator and refining variable partitioning to safely recognize aliases within a garbage-collected environment. By leveraging skills in Nim, JavaScript backend development, and static analysis, the work reduced redundant memory operations for objects, sequences, and arrays. The approach improved memory management efficiency in the JS backend, addressing common data structure handling without introducing new bugs, and demonstrated depth in compiler development practices.