.NET 10 support for SOEs and SOIs
Starting with ArcGIS Enterprise SDK 12.1, developing .NET-based SOEs and SOIs with .NET 10 is now supported. Developers can now build and deploy Server Object Extensions (SOEs) and Server Object Interceptors (SOIs) using the latest Microsoft .NET long-term support (LTS) release and Visual Studio 2026. For more information, see Overview of .NET 10 support for SOEs and SOIs.
PBF output format support on .Net extension
Starting with ArcGIS Enterprise SDK 12.1, Protocol Buffers (PBF) output format is supported for .NET extensions. Developers can now return responses in compact binary format by specifying the output format as "pbf".
PBF support helps improve response size and performance for supported REST operations, especially in high-volume or web mapping scenarios.
Utility Network support for telecom workflows
ArcGIS Enterprise SDK 12.1 includes enhancements that improve integration and extensibility for telecom implementations using the ArcGIS Utility Network. These updates help developers build SOEs and SOIs for telecommunications network management workflows. For a complete list of newly added interfaces and classes, refer to the What's New in 12.1 API documentation.