Code‑first guide to top .NET LLM open‑source projects in 2025: Extensions.AI, Semantic Kernel, LLamaSharp, ONNX Runtime, Whisper and vector DBs.
Top .NET AI/LLM Open‑Source Projects in 2025

Unlocking the Power of .NET – Empowering Developers, One Byte at a Time!

Code‑first guide to top .NET LLM open‑source projects in 2025: Extensions.AI, Semantic Kernel, LLamaSharp, ONNX Runtime, Whisper and vector DBs.

Build secure multi‑agent systems with Semantic Kernel in .NET: A2A handshake, orchestration patterns, and a research‑to‑summary pipeline.

Build fast, testable .NET CLIs with C#: System.CommandLine, DI, logging, Spectre.Console, exit codes, completion, and global tool packaging.

Build long‑term memory in .NET with Semantic Kernel. Compare Azure AI Search, Pinecone, pgvector, and ship reliable RAG.

Explore .NET 10 Preview 7: faster JSON via PipeReader, WebSocketStream, safer ASP.NET Core auth, EF Core LeftJoin, and MAUI XAML Source Gen.

Integrate ChatGPT into .NET like a pro: streaming, tools, JSON output, resilience, and tests. Copy‑paste C# you can ship today.