I think you mean "Envelop" (note the lack of trailing "e"). That was a neat tool, and community, back in the day. Too bad it didn't get anywhere.
It's also worth mentioning Sharpdevelop.net which also gave you the choice of VB.Net or C# and another language, can't recall what it was.
There were so many options available. So many books were written, sold and then became obsolete. I know because I bought tons of them at the now defunct Fry's Electronics and later donated them to the local public library.
But with AI advancing, focusing on programming and earning a CS degree as a future investment does not hold the same appeal that it once did. Of course, this is just my opinion.
Sol Roth: The Downvoted Man :)