STSdb is a free open-source embedded object database system (NoSQL key/value pair storage engine), coded in 100% pure managed C#. STSdb is designed for mission critical and real-time applications. It provides intuitive use and blazing performance.

The backbone of STSdb is WaterfallTree™ - patent pending technology of STS Soft SC. Formally W-tree is a natural generalization of B+-tree. In general operations in B+-tree are executed synchronously (one by one) while in W-tree operations are executed аsynchronously (in groups). As a result W-tree solves the problem of speed degradation when indexing records with random keys. This allows to maintain multiple indexes in real-time without harming system performance