Libuv not compatible with opam-monorepo

[tmattio]

This seems to be an issue caused by ocaml/dune#4121, however, I'm opening an issue here as well to track it on opam-monorepo.

This is preventing users from using eio in mono repositories at the moment (since the backend on macOS uses luv). I've pushed a small reproduction here: https://github.com/tmattio/repro-eio-monorepo.

The issue has been observed while trying to port https://github.com/moby/vpnkit to opam monorepo.

[NathanReb]

It seems indeed that it's not specific to opam-monorepo and does not work in opam either.

[talex5]

Looks like @patricoferris has a workaround: https://github.com/patricoferris/luv/tree/monorepo