# Update Nix to Unstable
**URL:** https://discourse.nixos.org/t/update-nix-to-unstable/9550
**Category:** Guides
**Created:** [October 19, 2020, 8:54pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550 "2020-10-19T20:54:56Z")
**Posts on this page:** 14
**Page:** 1
### Author:  [@jeff-hykin](https://discourse.nixos.org/u/jeff-hykin)
#### Post date: [October 19, 2020, 8:54pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/1 "2020-10-19T20:54:56Z")
Nix has an option to upgrade to stable
`upgrade-nix upgrade Nix to the latest stable version`
Is there a way for me to upgrade past that?
There is a bug [here](https://github.com/NixOS/nixpkgs/issues/68206) that was fixed 2 weeks ago, but even on the latest stable the bug still exists so I’d like to upgrade to so I can use the fix.
### Edit: Jump to [answer summary](https://discourse.nixos.org/t/update-nix-to-unstable/9550/10)
---
### Author:  [@jonringer](https://discourse.nixos.org/u/jonringer)
#### Post date: [October 19, 2020, 9:38pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/2 "2020-10-19T21:38:03Z")
generally this is done through channels.
You’ll want to set your nixpkgs channel to follow the release you want to “upgrade to”. Then you need to use “re-run” the command which consumes that channel
follow new channel:
```auto
nix-channel --add https://channels.nixos.org/nixos-20.09 nixos
```
“fetch” the channel and related package set
```auto
nix-channel --update
```
then run the command that “applies” a channel
```auto
nix-env -u '*'
home-manager switch
nix-shell -p ...
```
For upgrading your system, you’ll just want to run it as sudo
```auto
sudo nix-channel --add https://channels.nixos.org/nixos-20.09 nixos
```
then
```auto
sudo nixos-rebuild switch
```
EDIT: forgot update command
---
### Author:  [@jeff-hykin](https://discourse.nixos.org/u/jeff-hykin)
#### Post date: [October 19, 2020, 9:47pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/3 "2020-10-19T21:47:59Z")
@jonringer Thanks for the quick response! Sadly I’m not on nixos (the bug itself is a mac-specific)
I added the channel with
` nix-channel --add https://channels.nixos.org/nixpkgs-unstable/ unstable`
`nix-env -u '*'` is the only command that worked for me (I don’t have home-manager either).
I’m not sure what the `...` should be for nix-shell command.
---
### Author:  [@jonringer](https://discourse.nixos.org/u/jonringer)
#### Post date: [October 19, 2020, 9:53pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/4 "2020-10-19T21:53:32Z")
nix-shell just drops you into a shell with certain things present
[https://www.youtube.com/watch?v=k7NKBfeYXCk](https://www.youtube.com/watch?v=k7NKBfeYXCk) a video on it’s usage
---
### Author:  [@jeff-hykin](https://discourse.nixos.org/u/jeff-hykin)
#### Post date: [October 19, 2020, 10:03pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/5 "2020-10-19T22:03:31Z")
Thanks for the link! I use `nix-shell` pretty often, I just wasn’t sure why `nix-shell -p` would be needed for applying the update.
Sadly It looks like the change wasn’t applied, `nix --version` is still 2.3.7, and the bug still exists.
Edit: @jonringer oh that’s your video! Haha I actually watched it when I was trying to learn nix-shell, thanks for making it!
---
### Author:  [@NobbZ](https://discourse.nixos.org/u/NobbZ)
#### Post date: [October 19, 2020, 10:25pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/6 "2020-10-19T22:25:56Z")
Do you perhaps still have other channels active which might cause the issue?
---
### Author:  [@jeff-hykin](https://discourse.nixos.org/u/jeff-hykin)
#### Post date: [October 19, 2020, 10:35pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/7 "2020-10-19T22:35:53Z")
```auto
$ nix-channel --list
nixos https://channels.nixos.org/nixos-20.09
nixpkgs https://channels.nixos.org/nixpkgs-unstable
unstable https://channels.nixos.org/nixpkgs-unstable
```
After listing I went ahead and removed `unstable` and `nixos` since I was getting this error:
```auto
warning: name collision in input Nix expressions, skipping '/Users/jeffhykin/.nix-defexpr/channels_root/nixpkgs'
```
Removing them, then running `nix-channel --update` followed again with `nix-env -u '*' ` seems to be doing a whole lot of something (installing), so I’ll add a post once its finished
---
### Author:  [@jonringer](https://discourse.nixos.org/u/jonringer)
#### Post date: [October 19, 2020, 10:53pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/8 "2020-10-19T22:53:32Z")
Oh yea, I forgot to mention, after you’re tracking the channel, you need to do `nix-channel --update` to pull down the remote information.
---
### Author:  [@jeff-hykin](https://discourse.nixos.org/u/jeff-hykin)
#### Post date: [October 19, 2020, 10:53pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/9 "2020-10-19T22:53:32Z")
I’m just now realizing `nix-env -u '*'` is updating every individual package. I was about to say that wasn’t what I wanted to do, since the bug causes `nix-env -qa --json` to fail and I thought nix-env itself needed to be updated.
But the bug is gone now! So there must be something interestingly recursive about nix-env I don’t understand.
As a slight downside, I’m now getting the following warning with every command, even though I’m only subscribed to one channel now
```auto
warning: name collision in input Nix expressions, skipping '/Users/jeffhykin/.nix-defexpr/channels_root/nixpkgs'
```
Looks like it has something to do with this,
```auto
/Users/jeffhykin/.nix-defexpr/channels_root/nixpkgs@ -> /nix/store/kkym0q1g9cy7hxxdng2ivwlyv530mgqk-nixpkgs-20.09pre234801.1facbd61b17/nixpkgs
```
Probably from when I added the nixos channel. I’m not sure the best way to delete/remove it
---
### Author:  [@jeff-hykin](https://discourse.nixos.org/u/jeff-hykin)
#### Post date: [October 19, 2020, 11:09pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/10 "2020-10-19T23:09:35Z")
# Answer (summary)
If you’re not running NixOS, then
1. Give your nix-env access to the latest by running
`sudo nix-channel --update`
2. Update all of your packages (which will probably take awhile)
`nix-env -u '*'`
If you are running NixOS
1. `nix-channel --add https://channels.nixos.org/nixos-20.09 nixos`
2. `nix-env -u '*'`
3. (if you have home-manager) `home-manager switch`
4. (if you want to upgrade your system)
```auto
sudo nix-channel --add https://channels.nixos.org/nixos-20.09 nixos
sudo nixos-rebuild switch
```
---
### Author:  [@simonchatts](https://discourse.nixos.org/u/simonchatts)
#### Post date: [October 20, 2020, 8:20am UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/11 "2020-10-20T08:20:54Z")
Just to close the circle, the fix for the [nix-env -qa --json bug on Darwin](https://github.com/NixOS/nixpkgs/issues/68206) doesn’t involve the `nix` executable at all. Rather, it’s a fix within the `nixpkgs` collection of Nix expressions.
So just updating `nixpkgs` to a recent enough version is all you need to get the fix, as you discovered.
---
### Author:  [@jeff-hykin](https://discourse.nixos.org/u/jeff-hykin)
#### Post date: [October 20, 2020, 2:55pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/12 "2020-10-20T14:55:56Z")
Although this is a bit off topic, if I use the `-f` option for an older commit (example below) will I basically be re-introducing the bug? (will the nix-env be using the `-f` packages, or only looking/searching them)
```auto
nix-env -qa --json -f https://github.com/NixOS/nixpkgs-channels/archive/8414d8386b9a6b855b291fb3f01a4e3b04c08bbb.tar.gz > ~/testJson.json
```
---
### Author:  [@mattfbacon](https://discourse.nixos.org/u/mattfbacon)
#### Post date: [March 13, 2022, 7:27pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/13 "2022-03-13T19:27:02Z")
I made the mistake of adding the unstable channel to my user channels. Running `sudo nix-channel --list` revealed that the system channel was still on 21.11 and updating that fixed the issue.
---
### Author:  [@mattfbacon](https://discourse.nixos.org/u/mattfbacon)
#### Post date: [March 13, 2022, 7:27pm UTC](https://discourse.nixos.org/t/update-nix-to-unstable/9550/14 "2022-03-13T19:27:35Z")
Btw, I know this is old but it’s one of the first results on $SEARCH\_ENGINE.