Mem0 launched Dream, a background maintenance layer for agent memory. The release addresses a production problem that write-and-retrieve systems eventually accumulate: duplicate wording, facts that used to be true, and recurring patterns that never become an explicit memory.
Dream applies three operations. Merge folds a narrower memory into a newer, more complete replacement. Supersede connects an old fact to the fact that replaced it while retaining history. Synthesize creates a higher-level memory only when several independent observations support it and records the source memory IDs.
The maintenance lane stays off the request path, so add and search latency do not change. Nothing is deleted: lifecycle state and replacement pointers preserve auditability, immutable memories and exclude_from_dream are skipped, and clients can choose latest_only or include_merged retrieval behavior.
Dream is available to Pro and Enterprise users, runs weekly for eligible user IDs, and processes activity only after it is enabled. The broader architecture lesson is that durable agent memory needs compaction and provenance just as databases need vacuum, garbage collection, or LSM compaction.