winhttp is a native extension that binds the asynchronous WinHTTP API into a thin, hard-to-misuse Ruby HTTP client: system TLS via Schannel with the OS certificate store and revocation policy, the user's proxy and PAC settings, HTTP/2 negotiation, transparent gzip/deflate, safe redirect defaults, and streaming downloads. Requests park the calling fiber under a Fiber scheduler (e.g. winloop) and block plainly without one — one code path. Windows MSVC (mswin) Ruby only.