nix develop sets TMPDIR which changes the computed runtime dir between creating the shell and running devenv up.
DEVENV_RUNTIME changes from /tmp/devenv-<hash> to /tmp/nix-shell.<hash>/devenv-<hash>.
This makes the flake-based devenv up error out because process-compose expects the runtime dir to exists when creating the unix socket.
Non-flake devenv up is not affected by this, as it seems to create the new runtime dir before running the procfile.
On NixOS, this error doesn't show up because XDG_RUNTIME_DIR is set by default and is used as the tmpdir. This is not touched by nix develop.
Fixes #1153.
nix developsetsTMPDIRwhich changes the computed runtime dir between creating the shell and runningdevenv up.DEVENV_RUNTIMEchanges from/tmp/devenv-<hash>to/tmp/nix-shell.<hash>/devenv-<hash>.This makes the flake-based
devenv uperror out because process-compose expects the runtime dir to exists when creating the unix socket. Non-flakedevenv upis not affected by this, as it seems to create the new runtime dir before running the procfile.On NixOS, this error doesn't show up because
XDG_RUNTIME_DIRis set by default and is used as thetmpdir. This is not touched bynix develop.