Painless dependencies for Nix projects. Read more in the Getting started section below.
niv
is available in nixpkgs
as niv
:
$ nix-env -iA nixpkgs.niv
Alternatively, run the following command to install the development version:
$ nix-env -iA niv -f https://github.com/nmattia/niv/tarball/master \
--substituters https://niv.cachix.org \
--trusted-public-keys niv.cachix.org-1:X32PCg2e/zAm3/uD1ScqW2z/K0LtDyNV7RdaxIuLgQM=
Inside the provided nix shell:
$ repl
Run the test suite with this command:
$ ./script/test
niv
simplifies adding and updating dependencies in Nix
projects. It uses a single file, nix/sources.json
, where it stores the data
necessary for fetching and updating the packages.
- Add: inserts a package in
nix/sources.json
. - Update: updates one or all packages in
nix/sources.json
. - Drop: deletes a package from
nix/sources.json
.
niv
has some utility functions:
- Init: bootstraps a Nix project, in particular creates a
nix/sources.json
file containingniv
andnixpkgs
as well as anix/sources.nix
file that returns the sources as a Nix object. - Show: shows the packages' information.
- Modify: modifies attributes without performing an update.
The following environment variables are read by niv
:
Name | Note |
---|---|
GITHUB_TOKEN or NIV_GITHUB_TOKEN | When set, the value is used to authenticate GitHub API requests. |
GITHUB_HOST or NIV_GITHUB_HOST | The GitHub host to use when fetching packages. Port may be appended here. |
GITHUB_API_HOST or NIV_GITHUB_API_HOST | The host used when performing GitHub API requests. Use GITHUB_API_PORT for specifying the port. |
GITHUB_API_PORT or NIV_GITHUB_API_PORT | The port used when performing GitHub API requests. Defaults to 443 for secure requests. Defaults to 80 for insecure requests. See also: GITHUB_INSECURE . |
NIV_GITHUB_INSECURE | When set to anything but the empty string, requests are performed over http instead of https . |
NIV_GITHUB_PATH | The base path used when performing GitHub API requests. |
The next two sections cover common use cases and full command description.
This section covers common use cases:
- Bootstrapping a Nix project.
- Tracking a different nixpkgs branch.
- Importing packages from GitHub.
- Fetching packages from custom URLs.
Use the init
command when starting a new Nix project or when porting an
existing Nix project to niv:
$ niv init
...
$ tree
.
└── nix
  ├── sources.json
  └── sources.nix
1 directory, 2 files
The file nix/sources.json
is the file used by niv to store versions and is
initialized with niv and nixpkgs:
{
"nixpkgs": {
"url": "https://github.com/NixOS/nixpkgs/archive/109a28ab954a0ad129f7621d468f829981b8b96c.tar.gz",
"owner": "NixOS",
"branch": "nixos-19.09",
"url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz",
"repo": "nixpkgs",
"sha256": "12wnxla7ld4cgpdndaipdh3j4zdalifk287ihxhnmrzrghjahs3q",
"description": "Nix Packages collection",
"rev": "109a28ab954a0ad129f7621d468f829981b8b96c"
},
"niv": {
"homepage": "https://github.com/nmattia/niv",
"url": "https://github.com/nmattia/niv/archive/72e77204544527279e8f1e2d982d29503482b8f4.tar.gz",
"owner": "nmattia",
"branch": "master",
"url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz",
"repo": "niv",
"sha256": "1zjcyzxhq9iwxh58j5d7sx1vz5s3r1f6gpmnfgj2a3rxmclwvn3c",
"description": "Easy dependency management for Nix projects",
"rev": "72e77204544527279e8f1e2d982d29503482b8f4"
}
}
To use those dependencies import
the file nix/sources.nix
, e.g.:
{ sources ? import ./sources.nix }: # import the sources
with
{ overlay = _: pkgs:
{ niv = import sources.niv {}; # use the sources :)
};
};
import sources.nixpkgs # and use them again!
{ overlays = [ overlay ] ; config = {}; }
The init
command sets the nix/sources.json
file to track the latest commit
present on nixpkgs 19.09 when the command was run. Run the following command to
update it:
$ niv update nixpkgs
To change the branch being tracked run this command:
$ niv update nixpkgs -b nixos-19.09 # equivalent to --branch nixos-19.09
The add
command will infer information about the package being added, when
possible. This works very well for GitHub repositories. Run this command to add
jq to your project:
$ niv add stedolan/jq
The following data was added in nix/sources.json
for jq
:
{
"homepage": "http://stedolan.github.io/jq/",
"url": "https://github.com/stedolan/jq/archive/9fa2e51099c55af56e3e541dc4b399f11de74abe.tar.gz",
"owner": "stedolan",
"branch": "master",
"url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz",
"repo": "jq",
"sha256": "0819rvk8057qgcqvgn7fpldvly2pfdw9fxcjrlqa8gr59p8a1cic",
"description": "Command-line JSON processor",
"rev": "9fa2e51099c55af56e3e541dc4b399f11de74abe"
}
It is possible to use niv to fetch packages from custom URLs. Run this command
to add the Haskell compiler GHC to your nix/sources.json
:
$ niv add ghc \
-v 8.4.3 \
-t 'https://downloads.haskell.org/~ghc/<version>/ghc-<version>-i386-deb8-linux.tar.xz'
The option -v
sets the "version" attribute to 8.4.3
. The option -t
sets a
template that can be reused by niv when fetching a new URL (see the
documentation for add and update).
The type of the dependency is guessed from the provided URL template, if -T
is not specified.
For updating the version of GHC used run this command:
$ niv update ghc -v 8.6.2
niv - dependency manager for Nix projects
version: 0.2.18
Usage: niv [-s|--sources-file FILE] COMMAND
Available options:
-s,--sources-file FILE Use FILE instead of nix/sources.json
-h,--help Show this help text
--version Print version
Available commands:
init Initialize a Nix project. Existing files won't be
modified.
add Add a GitHub dependency
show
update Update dependencies
modify Modify dependency attributes without performing an
update
drop Drop dependency
Examples:
niv add stedolan/jq
niv add NixOS/nixpkgs -n nixpkgs -b nixpkgs-unstable
niv add my-package -v alpha-0.1 -t http://example.com/archive/<version>.zip
Usage: niv add PACKAGE [-n|--name NAME] ([-a|--attribute KEY=VAL] |
[-s|--string-attribute KEY=VAL] | [-b|--branch BRANCH] |
[-o|--owner OWNER] | [-r|--rev REV] | [-v|--version VERSION] |
[-t|--template URL] | [-T|--type TYPE])
Add a GitHub dependency
Available options:
-n,--name NAME Set the package name to <NAME>
-a,--attribute KEY=VAL Set the package spec attribute <KEY> to <VAL>, where
<VAL> may be JSON.
-s,--string-attribute KEY=VAL
Set the package spec attribute <KEY> to <VAL>.
-b,--branch BRANCH Equivalent to --attribute branch=<BRANCH>
-o,--owner OWNER Equivalent to --attribute owner=<OWNER>
-r,--rev REV Equivalent to --attribute rev=<REV>
-v,--version VERSION Equivalent to --attribute version=<VERSION>
-t,--template URL Used during 'update' when building URL. Occurrences
of <foo> are replaced with attribute 'foo'.
-T,--type TYPE The type of the URL target. The value can be either
'file' or 'tarball'. If not set, the value is
inferred from the suffix of the URL.
-h,--help Show this help text
Experimental commands:
git Add a git dependency. Experimental.
github Add a GitHub dependency
local Add a local dependency. Experimental.
Examples:
niv update # update all packages
niv update nixpkgs # update nixpkgs
niv update my-package -v beta-0.2 # update my-package to version "beta-0.2"
Usage: niv update [PACKAGE] ([-a|--attribute KEY=VAL] |
[-s|--string-attribute KEY=VAL] | [-b|--branch BRANCH] |
[-o|--owner OWNER] | [-r|--rev REV] | [-v|--version VERSION] |
[-t|--template URL] | [-T|--type TYPE])
Update dependencies
Available options:
-a,--attribute KEY=VAL Set the package spec attribute <KEY> to <VAL>, where
<VAL> may be JSON.
-s,--string-attribute KEY=VAL
Set the package spec attribute <KEY> to <VAL>.
-b,--branch BRANCH Equivalent to --attribute branch=<BRANCH>
-o,--owner OWNER Equivalent to --attribute owner=<OWNER>
-r,--rev REV Equivalent to --attribute rev=<REV>
-v,--version VERSION Equivalent to --attribute version=<VERSION>
-t,--template URL Used during 'update' when building URL. Occurrences
of <foo> are replaced with attribute 'foo'.
-T,--type TYPE The type of the URL target. The value can be either
'file' or 'tarball'. If not set, the value is
inferred from the suffix of the URL.
-h,--help Show this help text
Examples:
niv modify nixpkgs -v beta-0.2
niv modify nixpkgs -a branch=nixpkgs-unstable
Usage: niv modify PACKAGE [-n|--name NAME] ([-a|--attribute KEY=VAL] |
[-s|--string-attribute KEY=VAL] | [-b|--branch BRANCH] |
[-o|--owner OWNER] | [-r|--rev REV] | [-v|--version VERSION] |
[-t|--template URL] | [-T|--type TYPE])
Modify dependency attributes without performing an update
Available options:
-n,--name NAME Set the package name to <NAME>
-a,--attribute KEY=VAL Set the package spec attribute <KEY> to <VAL>, where
<VAL> may be JSON.
-s,--string-attribute KEY=VAL
Set the package spec attribute <KEY> to <VAL>.
-b,--branch BRANCH Equivalent to --attribute branch=<BRANCH>
-o,--owner OWNER Equivalent to --attribute owner=<OWNER>
-r,--rev REV Equivalent to --attribute rev=<REV>
-v,--version VERSION Equivalent to --attribute version=<VERSION>
-t,--template URL Used during 'update' when building URL. Occurrences
of <foo> are replaced with attribute 'foo'.
-T,--type TYPE The type of the URL target. The value can be either
'file' or 'tarball'. If not set, the value is
inferred from the suffix of the URL.
-h,--help Show this help text
Examples:
niv drop jq
niv drop my-package version
Usage: niv drop PACKAGE [ATTRIBUTE]
Drop dependency
Available options:
-h,--help Show this help text
Usage: niv init ([--no-nixpkgs] | [-b|--nixpkgs-branch ARG]
[--nixpkgs OWNER/REPO])
Initialize a Nix project. Existing files won't be modified.
Available options:
--no-nixpkgs Don't add a nixpkgs entry to sources.json.
-b,--nixpkgs-branch ARG The nixpkgs branch to use. (default: "release-20.03")
--nixpkgs OWNER/REPO Use a custom nixpkgs repository from
GitHub. (default: NixOS/nixpkgs)
-h,--help Show this help text
Usage: niv show [PACKAGE]
Available options:
-h,--help Show this help text
- Can I use private GitHub repositories?
- How do I import a subpath of a source?
- How do I import NixOS modules
- Can I use local packages?
Yes. There are two ways:
When using the git protocol, your public SSH keypair is used to authenticate you:
$ niv add git git@github.com:my_user/my_private_repo
in order to niv add
a private github repo you'll need to:
- create a .netrc file with the following content
machine github.com
login YOUR_GITHUB_USER_NAME
password YOUR_GITHUB_TOKEN
- add the path to the above file to
/etc/nix/nix.conf
:
netrc-file = /PATH/TO/.netrc
- set
GITHUB_TOKEN
env var when callingniv add
GITHUB_TOKEN=$YOUR_GITHUB_TOKEN niv add ...
In order to use the directory dir
of a my-package
, use the following
pattern:
let
sources = import ./nix/sources.nix;
in sources.my-package + "/dir"
in this example, sources.my-package
becomes my-package
's root directory, and + "/dir"
appends the
subdirectory.
After the package containing the modules has been niv add
ed, importing the
modules is straightforward:
let
sources = import ./nix/sources.nix;
in {
imports = [ (sources.package + "/path/to/module") ];
}
If you need to use a local path as a source -- especially convenient when
modifying dependencies -- niv
allows you to override the sources.json
via
environment variables. To override a source foo
with a local path
./bar/baz
, set the environment variable NIV_OVERRIDE_foo
to ./bar/baz
.
Generally, if the environment variable NIV_OVERRIDE_<name>
is set and you
have a source named <name>
then niv
will use the value of
NIV_OVERRIDE_<name>
as the outPath
of that source. All non-alphanumeric
characters in the source name are escaped to the character _
; i.e. to
override the package my package-foo
you need to set the environment variable
NIV_OVERRIDE_my_package_foo
.