Exploring the .NET Open Source Application 2026

This blog post is a summary of a talk I gave at the .NET Thailand Developer Day 2026 at Seven Peaks, 5F The PARQ, Bangkok. The idea for this topic came from attending FOSSASIA 2026 Community Day, where I listened to a talk titled “Recommend Open Source apps to a new user.” This got me thinking about the .NET side — ever since .NET became open source back in 2017, now in 2026, let’s take a look at what has grown beyond just libraries. We’ve seen many great ones such as RestSharp / Serilog (Logging) / NUnit (Testing) / OpenTelemetry…








