Bio: Leon Havin

Leon Havin

Leon started his professional career as an Aeronautical Engineer and Officer in the Air Force, and later acting as Deputy Program Manager in aerospace corporation. His first coding adventures were in VB and Assembly, followed by C at the dawn of Windows and TCP/IP stack era. After a decade of coding client/server apps with C++/MFC and COM, Leon founded Gravity Storm Software, LLC., the first Security Patch Management software on the market for enterprise networks. After successfully running it for over 8 years, Leon accepted the position of Principal Software Engineer in Broadcom, followed by the role of Software Architect with Phoenix Technologies, in which he developed Bluetooth applications and chip test tools. Subsequently, Leon got hooked on C# and became involved in developing telephony applications with SIP stack, WCF Web Services, WinForms, WPF, and DevExpress, and also specialized in Microsoft Office VSTO Add-ins. Throughout the last decade, Leon has been contracting locally from San Diego, California, successfully completing 75 projects for remote and freelance clients.

When not working Leon enjoys trying his hand in developing IoT prototypes with variety of sensors: UWB system for RTLS, GPS Trackers, and mobile EKG – all using LTE-M network for communication.
He is also a frequent walker and sprint runner at local Del Mar beach.


  • General: C#/.NET 2.0 through 6.0, WinForms, WPF, XML, JSON, WMI, LINQ, IPC, Windows Services and Service Controllers
  • Databases: SQL, SQLite, Mongo, Entity Framework
  • Networking: HTTP, RPC, FTP, IGMP, SNMP, Sockets, Bluetooth, RS232/RS485, MQTT
  • Security: PGP Encryption/Decryption (PKI), AES256, SHA256, Security Certificate generation API, Bouncy Castle
  • Web Services: RESTful API, WCF Servers and Clients, gRPC Microservices
  • Office: MS Office Add-In with VSTO and Add-In Express
  • Legacy: Win32, C/C++, Python, MFC, ATL, COM/DCOM, ActiveX
  • Developed: Advanced GUI, Multithreading/Thread Synchronization, Async/Overlapped I/O, Windows Services, Web Services/WCF, High-Performance I/O Engines, Multi-tier Client/Server Architectures, Windows Shell and Namespace Extensions, Windows Networking API, OBEX FTP client, C++ FTP Client with WinSock, TCP/IP packet-level encryption, Multicast socket engines, Bluetooth over Winsock API, Modbus Interface
  • Tools: Visual Studio through 2019/2022, DevExpress, Add-In Express, Eclipse, GIT, SVN, JIRA, Bugzilla, Perforce, Advanced Installer, WireShark, Dynatrace Clients

Contact Information:

  • Phone: 8586922281