The Microsoft AI team builds comprehensive content, services, platforms, and technology for consumers to get the information they want on any device, anywhere, and for enterprises to improve their customer and employee experiences. Our team powers several experiences such as Bing, Copilot, Advertising, Maps and Edge, surfacing through entry points like the Edge New Tab Page, Windows 10 and 11, which have over 1 billion monthly active users. We realized the need for a high-performance and reliable gateway to be the front-end and ingress layer for Microsoft AI. This would enable multiple teams to leverage the common capabilities we developed to help run the business and focus on customer experience & features. In this blog post, we will cover the journey to building our gateway, codenamed CETO, with the help of YARP on .NET 8. Before we could start coding CETO, we had to decide on a reverse proxy. Should we use an external one or try to make our own? Would these external ones cover all our use cases? We also had to consider the high cost and continual upkeep for customizing those proxies. We had requirements such as supporting HTTP/2, HTTP/3, streaming protocols like WebSocket, simple extensibility, and more. As we started to look around at what other internal teams at Microsoft were doing, we came across the YARP project. YARP stands for: “Yet Another Reverse Proxy”. The project uses ASP.NET and .NET (.NET 6 and newer) to offer a flexible solution that can be modified via .NET code. How convenient is that? It turned out to be just what we needed. Bing runs one of the world’s largest, highly performant, and reliable .NET applications. We have relied on a close working relationship with the .NET team and have been early adopters of each of .NET release. By trying out and upgrading to each new version, we can give useful feedback to the .NET team. This helps our platform and external customers
