In high school, I think I worked for a company that has prior art on deployless software. We wrote php and perl directly on the prod server with vi through putty. No deploy necessary!
Well, with compiled languages and multiple servers it does get a bit more complex.
But yes, these online editor products have been created before and afaik they rarely get significant traction. Yet, even a small user base might make it profitable, so it does make sense, and hence these companies.
> Well, with compiled languages and multiple servers it does get a bit more complex.
Compiling (and basically anything) can be done as a cgi script (https://github.com/RhysU/c99sh), I bet you could go a long way with that on a network drive or with an rsync daemon.
Dark founder here. Many people remember writing directly on the server quite fondly, because it had a great turnaround. But we stopped doing it because it wasn't safe. Dark makes it safe [1], so you can start doing it again.
We actually did have Visual Studio installed in at least one test server