Techniques are provided for managing objects within an object store. An object is maintained within an object store. The object comprises a plurality of slots. Each slot is used to store a unit of data accessible to applications hosted by remote computing devices. The object comprises an object header used to store metadata for each slot. A determination is made that the object is a fragmented object comprising an in-use slot of in-use data and a freed slot from which data was freed. The object is compacted to retain in-use data and exclude freed data as a rewritten object.