Nix Daemon disconnects on fresh install (MacOS)

[Dandandooo]

Describe the bug

I uninstalled Nix following the guide for the multi-user install. I then reinstall the multi-user installation of nix. I am running the latest MacOS 15.2 Developer beta. When I run any nix-shell -p command, I get the following error:

error: Nix daemon disconnected unexpectedly (maybe it crashed?)

There is no other output.

When I run launchctl list | grep nix, there is no output.
When I run 'nix-daemon' I get:

error: cannot bind to socket at '/nix/var/nix/daemon-socket/socket': Address already in use

Steps To Reproduce

1. sh <(curl -L https://nixos.org/nix/install)
2. restart
3. nix-shell -p nix-info --run "nix-info -m" or any other nix-shell command

Expected behavior

I should run without error

Metadata

nix-env (Nix) 2.25.3

Additional context

I am running the latest MacOS 15.2 Developer Beta. I have leftover nix files in my system, but I performed the full uninstall procedure listed on the guide.

Checklist

• checked latest Nix manual (source)
• checked open bug issues and pull requests for possible duplicates

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[abathur]

Is there a crash dump in console.app?

[Dandandooo]

Yes there is. This is the latest one (copied to plaintext instead of .ips):
nix-crash.txt

[abathur]

Thanks--hopefully that'll light the way.

If you need to get Nix running, I'd try uninstalling and then installing some other recent versions to see if this is new trouble (hopefully not something to do with 15.2...).

I'd start with the most recent 2.24 and 2.18 releases.

[GiyoMoon]

I just updated MacOS from 15.1.1 to 15.2 and I'm facing the same error

❯ nix config check
[PASS] PATH contains only one nix version.
[PASS] All profiles are gcroots.
error: cannot connect to socket at '/nix/var/nix/daemon-socket/socket': Connection refused
❯ nix --version
nix (Nix) 2.24.10

nix-daemon seems to be running but my user can't access it. (launchctl print system/org.nixos.nix-daemon says state = running)

[abathur]

With the caveat that this may actually be two separate issues (despite the socket being a point of commonality, the exact error and state of the daemon differs):

I checked in on Matrix and found at least one person (also running 2.24.10) able to affirm that they've taken the 15.2 update without seeing either of these errors.

I'm not familiar with what is going on here, but I'm taking it as a sign that this isn't a global issue with 15.2.

Unless someone happens by who knows what's going on: In both cases, it might also help to spend a little time trawling the full device log in Console.app around the time of your invocations and around daemon startup (may need to stop and start it) to see if there's anything that smells related.

The only real hunch I've got at the moment is that sometimes people disable a permission at some point (often because they notice something's unhelpfully just listed as "sh" because it's a wrapper and think it looks suspicious) and then an OS update leads to new enforcement/consequences for that previous action. Worth checking for anything like that to toggle it back on for a test.

[GiyoMoon]

Running the update command from the nix manual fixed it for me!
https://nix.dev/manual/nix/2.17/installation/upgrading
The version stayed the same (2.24.10) so I assume something was wrong on my side locally hm.

[Dandandooo]

I tried this and it didn't fix it for me. Same error message

[cole-h]

Seems similar to #11918, which has a comment linking to another potential solution: https://discourse.nixos.org/t/ssl-ca-cert-error-on-macos/31171/5