Probably the most under-utilised feature is HTTP pipelining. For example, almost all dev tools are single-threaded and synchronous. This includes package manag

Probably the most under-utilised feature is HTTP pipelining. For example, almost all dev tools are single-threaded and synchronous. This includes package management tools like Cargo and NuGet, and also debug symbol downloaders like WinDbg. Starting a debug session in Visual Studio is an excuse to go get a coffee… outside at a cafe. It’ll take it ten minutes to download a few megabytes of symbols over gigabit fibre. One. File. At… a… time.