forked from mirrors/nixpkgs
78 lines
2.6 KiB
Markdown
78 lines
2.6 KiB
Markdown
# Getting the Sources {#sec-getting-sources}
|
|
|
|
By default, NixOS's `nixos-rebuild` command uses the NixOS and Nixpkgs
|
|
sources provided by the `nixos` channel (kept in
|
|
`/nix/var/nix/profiles/per-user/root/channels/nixos`). To modify NixOS,
|
|
however, you should check out the latest sources from Git. This is as
|
|
follows:
|
|
|
|
```ShellSession
|
|
$ git clone https://github.com/NixOS/nixpkgs
|
|
$ cd nixpkgs
|
|
$ git remote update origin
|
|
```
|
|
|
|
This will check out the latest Nixpkgs sources to `./nixpkgs` the NixOS
|
|
sources to `./nixpkgs/nixos`. (The NixOS source tree lives in a
|
|
subdirectory of the Nixpkgs repository.) The `nixpkgs` repository has
|
|
branches that correspond to each Nixpkgs/NixOS channel (see
|
|
[](#sec-upgrading) for more information about channels). Thus, the
|
|
Git branch `origin/nixos-17.03` will contain the latest built and tested
|
|
version available in the `nixos-17.03` channel.
|
|
|
|
It's often inconvenient to develop directly on the master branch, since
|
|
if somebody has just committed (say) a change to GCC, then the binary
|
|
cache may not have caught up yet and you'll have to rebuild everything
|
|
from source. So you may want to create a local branch based on your
|
|
current NixOS version:
|
|
|
|
```ShellSession
|
|
$ nixos-version
|
|
17.09pre104379.6e0b727 (Hummingbird)
|
|
|
|
$ git checkout -b local 6e0b727
|
|
```
|
|
|
|
Or, to base your local branch on the latest version available in a NixOS
|
|
channel:
|
|
|
|
```ShellSession
|
|
$ git remote update origin
|
|
$ git checkout -b local origin/nixos-17.03
|
|
```
|
|
|
|
(Replace `nixos-17.03` with the name of the channel you want to use.)
|
|
You can use `git merge` or `git
|
|
rebase` to keep your local branch in sync with the channel, e.g.
|
|
|
|
```ShellSession
|
|
$ git remote update origin
|
|
$ git merge origin/nixos-17.03
|
|
```
|
|
|
|
You can use `git cherry-pick` to copy commits from your local branch to
|
|
the upstream branch.
|
|
|
|
If you want to rebuild your system using your (modified) sources, you
|
|
need to tell `nixos-rebuild` about them using the `-I` flag:
|
|
|
|
```ShellSession
|
|
# nixos-rebuild switch -I nixpkgs=/my/sources/nixpkgs
|
|
```
|
|
|
|
If you want `nix-env` to use the expressions in `/my/sources`, use
|
|
`nix-env -f
|
|
/my/sources/nixpkgs`, or change the default by adding a symlink in
|
|
`~/.nix-defexpr`:
|
|
|
|
```ShellSession
|
|
$ ln -s /my/sources/nixpkgs ~/.nix-defexpr/nixpkgs
|
|
```
|
|
|
|
You may want to delete the symlink `~/.nix-defexpr/channels_root` to
|
|
prevent root's NixOS channel from clashing with your own tree (this may
|
|
break the command-not-found utility though). If you want to go back to
|
|
the default state, you may just remove the `~/.nix-defexpr` directory
|
|
completely, log out and log in again and it should have been recreated
|
|
with a link to the root channels.
|