A developer building a memory engine asks about production experience with tools such as mem0, Zep and Supermemory. The post questions whether public benchmark results translate into long-running conversations; it does not publish comparative findings that establish a superior product. A related benchmark, LongMemEval, tests abilities including cross-session integration, temporal reasoning, knowledge updates and abstention. Benchmark scores alone do not establish operating reliability or cost, so evaluation should also examine one’s own conversation data and failure cases.