6 KiB
Basic Usage in Nix Expressions:
mkPython / mkPythonShell
build a python environment from a list of requirements
let
mach-nix = import (builtins.fetchGit {
url = "https://github.com/DavHau/mach-nix/";
ref = "2.1.0";
});
in mach-nix.mkPython {
requirements = builtins.readFile ./requirements.txt;
}
buildPythonPackage / buildPythonApplication
Build a python package from its source code and a list of requirements
let
mach-nix = import (builtins.fetchGit {
url = "https://github.com/DavHau/mach-nix/";
ref = "2.1.0";
});
in mach-nix.buildPythonPackage {
pname = "my-package";
version = "1.0.0";
src = /project-path;
requirements = builtins.readFile /project-path/requirements.txt;
}
buildPythonPackage from GitHub
Build a python package from its source code and a list of requirements
let
mach-nix = import (builtins.fetchGit {
url = "https://github.com/DavHau/mach-nix/";
ref = "2.1.0";
});
in mach-nix.buildPythonPackage rec {
pname = "projectname";
version = "1.0.0";
src = builtins.fetchGit{
url = "https://github.com/user/projectname";
ref = "master";
# rev = "put_commit_hash_here";
};
doCheck = false;
doInstallCheck = false;
requirements = builtins.readFile "${src}/requirements.txt";
}
Examples for Tensorflow / PyTorch
Tensorflow with SSE/AVX/FMA support
I have a complex set of requirements including tensorflow. I'd like to have tensorflow with the usual nix features enabled like SSE/AVX/FMA which I cannot get from pypi. Therefore I must take tensorflow from nixpkgs. For everything else I keep the default, which means wheels are preferred. This allows for quicker installation of dependencies.
let
mach-nix = import (builtins.fetchGit {
url = "https://github.com/DavHau/mach-nix/";
ref = "2.1.0";
});
in mach-nix.mkPython {
requirements = ''
# bunch of other requirements
tensorflow
'';
providers = {
# force tensorflow to be taken from nixpkgs
tensorflow = "nixpkgs";
};
}
This only works if the restrictions in requirements.txt
allow for the tensorflow version from nixpkgs.
Tensorflow via wheel (newer versions, quicker builds)
I'd like to install a more recent version of tensorflow which is not available from nixpkgs. Also I don't like long build times and therefore I want to install tensorflow via wheel. Usually most wheels work pretty well out of the box, but the tensorflow wheel has an issue which I need to fix with an override.
let
mach-nix = import (builtins.fetchGit {
url = "https://github.com/DavHau/mach-nix/";
ref = "2.1.0";
});
in mach-nix.mkPython {
requirements = ''
# bunch of other requirements
tensorflow == 2.2.0rc4
'';
# no need to specify provider settings since wheel is the default anyways
# Fix the tensorflow wheel
overrides_post = [( pythonSelf: pythonSuper: {
tensorflow = pythonSuper.tensorflow.overridePythonAttrs ( oldAttrs: {
postInstall = ''
rm $out/bin/tensorboard
'';
});
})];
}
Recent PyTorch with nixpkgs dependencies, overlays, and custom python
I'd like to use a recent version of Pytorch from wheel, but I'd like to build the rest of the requirements from sdist or nixpkgs, since I've already written overlays for those packages which I'd like to continue using. Also I require python 3.6
let
mach-nix = import (builtins.fetchGit {
url = "https://github.com/DavHau/mach-nix/";
ref = "2.1.0";
});
overlays = []; # some very useful overlays
in mach-nix.mkPython rec {
requirements = ''
# bunch of other requirements
torch == 1.5.0
'';
providers = {
# disallow wheels by default
_default = "nixpkgs,sdist";
# allow wheels only for torch
torch = "wheel";
};
# Include my own overlay.
pkgs = import <nixpkgs> { config = { allowUnfree = true; }; inherit overlays; };
# Select custom python version (Must be taken from pkgs with the overlay applied)
python = pkgs.python36;
}
Using overrides
Fixing packages via overrides
See previous example for tensorflow wheel
Include poetry2nix overrides
I have a complex requirements.txt which includes imagecodecs
. It is available via wheel, but I prefer to build everything from source. This package has complex build dependencies and is not available from nixpkgs. Luckily poetry2nix` overrides make it work. The peotry2nix overrides depend on nixpkgs-unstable.
let
mach-nix = import (builtins.fetchGit {
url = "https://github.com/DavHau/mach-nix/";
ref = "2.1.0";
});
in mach-nix.mkPython rec {
requirements = ''
# bunch of other requirements
imagecodecs
'';
providers = {
_default = "sdist";
};
# Use unstable channel
pkgs = import <unstable> {};
# Import overrides from poetry2nix
# Caution! Use poetry2nix overrides only in `overrides_post`, not `overrides_pre`.
overrides_post = [
(
import (builtins.fetchurl {
url = "https://raw.githubusercontent.com/nix-community/poetry2nix/1cfaa4084d651d73af137866622e3d0699851008/overrides.nix";
}) { inherit pkgs; }
)
];
}