During a lightning talk at PromCon EU, Grafana Labs developer Callum Styan discussed significant improvements to Prometheus' remote write feature, the culmination of a six-month effort. Originally, remote write had issues with buffering unsent samples in memory, leading to data loss if the buffer filled up, which could crash the system (OOMkill). The new approach involves using Prometheus' existing write-ahead log (WAL), which records all necessary data, thus creating an on-disk buffer that prevents memory overflow and data loss by not reading more data if the buffer is full. This change means remote write now uses more memory under normal conditions but avoids crashing in worst-case scenarios. Additional work continues, including improving sharding and other enhancements to refine the system further.