AndreMouche worked on the pingcap/tidb-engine-ext repository, delivering a targeted optimization to the Raftstore compaction process. By adjusting the compaction order to process the write column family before the default column family, AndreMouche reduced unnecessary I/O and improved write-path efficiency, particularly for workloads with frequent deletions and active compaction-filters. This change required a deep understanding of database internals, distributed systems, and the semantics of column families within RocksDB. Implemented in Rust, the solution enhanced both the reliability and maintainability of the compaction pipeline, demonstrating thoughtful engineering and a focused approach to performance optimization in a complex storage environment.