Microsoft quietly published 9 production-ready .NET libraries Most .NET developers have no idea they exist 👇 They're official and open-source. Microsoft runs them inside its own production services. Each one is a separate NuGet package. You install only what you need, with no extra baggage. 𝟭. 𝗔𝗜 IChatClient gives you one API for OpenAI, Azure OpenAI, Ollama, and more. Switch providers without rewriting your code. 𝟮. 𝗥𝗲𝘀𝗶𝗹𝗶𝗲𝗻𝗰𝗲 One call to AddStandardResilienceHandler() adds retries, timeouts, a circuit breaker, and rate limiting to HttpClient. 𝟯. 𝗧𝗲𝗹𝗲𝗺𝗲𝘁𝗿𝘆 The [LogProperties] attribute logs every property of an object as its own structured field. 𝟰. 𝗖𝗼𝗺𝗽𝗹𝗶𝗮𝗻𝗰𝗲 Tag sensitive fields once, and emails or card numbers get redacted in your logs. 𝟱. 𝗗𝗶𝗮𝗴𝗻𝗼𝘀𝘁𝗶𝗰𝘀 Health checks for Kubernetes liveness and readiness probes, plus CPU and memory monitoring. 𝟲. 𝗖𝗼𝗻𝘁𝗲𝘅𝘁𝘂𝗮𝗹 𝗢𝗽𝘁𝗶𝗼𝗻𝘀 Config values that change per user, tenant, or request. 𝟳. 𝗔𝗦𝗣.𝗡𝗘𝗧 𝗖𝗼𝗿𝗲 𝗘𝘅𝘁𝗲𝗻𝘀𝗶𝗼𝗻𝘀 Measures latency for each stage of the request pipeline, so you see exactly where the time goes. 𝟴. 𝗦𝘁𝗮𝘁𝗶𝗰 𝗔𝗻𝗮𝗹𝘆𝘀𝗶𝘀 Microsoft's curated Roslyn analyzer rules, shipped as one NuGet package. 𝟵. 𝗧𝗲𝘀𝘁𝗶𝗻𝗴 FakeTimeProvider moves time forward instantly. FakeLogger lets you assert on log output. 📌 Explore the repo here: github.com/dotnet/extensions I still see teams write this code by hand: → A custom retry loop with Task.Delay → A regex that masks emails before logging → A test that waits 30 seconds for a cache to expire Each one is more code you have to debug and maintain yourself. ❌ Hand-rolled helpers → your bugs, your maintenance ✅ Microsoft's packages → tested at scale, maintained by the .NET team Before you write your next helper class, check this repo first. Have you tried any of these libraries?