Edit and Continue appeared in VS 4, 5 or 6 (can’t remember which one exactly), right before the first VS for .NET which I think was released in 2002. It supported C/C++ out of the box and required quite complex linker plumbing. Second .NET VS was 7.1, releases in 2003, before MS switched to confusing year-versioning in user-facing contexts and number versioning internally (including installation directories, project files, etc), which is made way worse because these days internal versions and years are off by two or three units (ie, Vs2018 is internally version 16 or 17, can never remember). My commercial vi/vim emulator, ViEmu, supported VS.NET 7.1/2003 on its initial release in 2005, and I still maintain that build, as in I build for that target every new ViEmu release and occasionally use it (it’s a much leaner and more stable debugging environment than more recent VS versions).