Aerospike is a key-value store designed to support extremely low latency create, read, update, and delete (CRUD) operations. It stores data as individual records that are uniformly distributed across all nodes of the database cluster. User-specified keys can be associated with each record along with application data. Aerospike uses the RIPEMD-160 hashing algorithm, which has a statistically near-zero probability of hash collision. By default, Aerospike does not store the user-supplied key with the saved record, but applications have the option to do so via the write policy. If two keys hash to the same digest value, resulting in a hash collision, Aerospike verifies the hash against the stored key during CRUD operations and throws a KEY_MISMATCH error if they are different. The user-stored key can be retrieved back to the client for data modeling purposes and queries, but not for single key reads. Aerospike provides expressions that can access the user-stored key, which are a strongly typed domain-specific language designed for manipulating and comparing bins and record metadata. These expressions can be used as filters for selecting records or compute on a record's existing data or metadata.