nix + opam :memo: ようわからんけどsandboxはずす (いいのか？)
[ERROR] Sandboxing is not working on your platform ubuntu:
"~/.opam/opam-init/hooks/sandbox.sh build sh -c echo SUCCESS >$TMPDIR/opam-sandbox-check-out && cat $TMPDIR/opam-sandbox-check-out; rm
-f $TMPDIR/opam-sandbox-check-out" exited with code 1 "bwrap: loopback: Failed RTM_NEWADDR: Operation not permitted"