STSdb 3.5 is a NoSQL key-value store open-source database. The database is written in C# using Microsoft .NET Framework. STSdb 3.5 is specifically designed for mission critical and real-time systems: stock exchanges, telecoms, research laboratories, industrial automation, SCADA, HMI, OLE for Process Control and etc. The main requirement for STSdb 3.5 was the ability to work with large data flows.