Deno's success is of course a concern for me personally because https://dropserver.org depends on it for its sandbox.
Personally I think there is a good chance they'll be around for a while. What they have is good, it just takes a while for enough people to notice, and start writing code for the runtime. I expect the next gen of tools to be poly-runtime. It's not just because of Deno: there are also cloudflare workers and other runtimes to target.
Also it seems they have figured out they can't get far by asking devs to rewrite their code for Deno or to be runtime agnostic.
So they are making improvements to their node compatibility. If thy can get that nailed down, this could be a big help for them (and for Dropserver too!)
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