Worked on the erlang/otp repository to deliver a targeted file I/O performance optimization focused on the write path. The approach involved skipping read buffer allocations for files opened in write mode and removing unnecessary seek operations when files were opened exclusively for writing. By reducing memory usage and minimizing system call overhead, the changes improved write throughput and lowered latency for I/O-intensive workloads. The optimization was implemented internally to maintain API compatibility and minimize risk, with all modifications isolated to the prim_file write path. Utilized Erlang, system calls, and performance tuning techniques to address scalability and efficiency in production environments.