I saw it, but I am not sure hot to leverage it in my case.

Gunicorn is ran through a python script calling Popen.

Hello, we are trying to build pendulum-3.0.0

Without any overrides, we get the following error:
ModuleNotFoundError: No module named 'maturin'
With this override:
buildInputs = (old.buildInputs or [ ]) ++ [ self.maturin ];

We also get the same error.
Searching the code of poetry2nix, we find out some references to maturin, so we did the following override:

pendulum = super.pendulum.overridePythonAttrs (
            old: {
              nativeBuildInputs = (old.nativeBuildInputs or [ ]) ++ [
                pkgs.cargo
                pkgs.rustc
                pkgs.maturin
                # pkgs.rustPlatform.cargoSetupHook
                pkgs.rustPlatform.maturinBuildHook
              ];
              buildInputs = (old.buildInputs or [ ]) ++ [ self.maturin ];
            }
          );

  Now the error is the following:

Executing maturinBuildHook
++ env CC_X86_64_UNKNOWN_LINUX_GNU=/nix/store/62zpnw69ylcfhcpy1di8152zlzmbls91-gcc-wrapper-13.3.0/bin/cc CXX_X86_64_UNKNOWN_LINUX_GN>
error: no matching package named pyo3 found
location searched: registry crates-io
required by package _pendulum v3.0.0 (/build/pendulum-3.0.0/rust)
As a reminder, you're using offline mode (--offline) which can sometimes cause surprising resolution failures, if this error is too >
💥 maturin failed
Caused by: Cargo metadata failed. Does your crate compile with cargo build?
Caused by: cargo metadata exited with an error:

We are out of ideas.

Any ideas?

Ok so using this in my flake :

Ok so using this in my flake :

     in
        {
        packages = {
          default = lookylooApp.dependencyEnv;
        };

make gunicorn available at ./result/bin.
Running gunicorn manualy (without the Popen but from my shell) is working.

I think the problem might come from the python script with a Popen calling gunicorn but "not the gunicorn from my flake"

How can I force the script to use the "generated" gunicorn ?

Should I replace the exe inside the python script ?
Should I update the PATH env, and how ?

I did found a solution :

{
  description = "Application packaged using poetry2nix";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    flake-utils = {
      url = "github:numtide/flake-utils";
    };
    poetry2nix = {
      #url = "github:nix-community/poetry2nix";
      url = "git+https://gitea.com/oven_spinout988/poetry2nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = { self, nixpkgs, flake-utils, poetry2nix }:
    flake-utils.lib.eachDefaultSystem
    (system:
    let

      [...]

      lookylooApp = let
        lookylooApp = pkgs.poetry2nix.mkPoetryApplication
          {
            inherit projectDir;
            inherit propagatedBuildInputs;
            overrides = p2n-overrides;
          };
        in lookylooApp.overrideAttrs (old: {
          postInstall = (if lookylooApp ? old then old else '''') + ''
            substituteInPlace $out/lib/${lookylooApp.python.executable}/site-packages/bin/start_website.py \
            --replace "gunicorn" "${lookylooApp.dependencyEnv}/bin/gunicorn"
          '';
        });
    in
      {
        packages = {
          default = lookylooApp;
        };
      };
}

Please let me know if the code can be improved

I did found a solution :

{
  description = "Application packaged using poetry2nix";

  inputs = {
    [...]
  };

  outputs = { self, nixpkgs, flake-utils, poetry2nix }:
    flake-utils.lib.eachDefaultSystem
    (system:
    let

      [...]

      lookylooApp = let
        lookylooApp = pkgs.poetry2nix.mkPoetryApplication
          {
            inherit projectDir;
            inherit propagatedBuildInputs;
            overrides = p2n-overrides;
          };
        in lookylooApp.overrideAttrs (old: {
          postInstall = (if lookylooApp ? old then old else '''') + ''
            substituteInPlace $out/lib/${lookylooApp.python.executable}/site-packages/bin/start_website.py \
            --replace "gunicorn" "${lookylooApp.dependencyEnv}/bin/gunicorn"
          '';
        });
    in
      {
        packages = {
          default = lookylooApp;
        };
      };
}

Please let me know if the code can be improved

class StandaloneApplication(gunicorn.app.base.BaseApplication):
    def __init__(self, app, options=None):
        self.options = options or {}
        self.application = app
        super().__init__()

    def load_config(self):
        config = {
            key: value
            for key, value in self.options.items()
            if key in self.cfg.settings and value is not None
        }
        for key, value in config.items():
            self.cfg.set(key.lower(), value)

    def load(self):
        return self.application

Hey, I'm having an issue with getting pytorch to build. I have a minimal config which works fine:
https://github.com/volkswagenfeature/minimalTorchRocm/tree/a9c7cd346e3a2493cc20489407df0d1f59d82d9f

But once I add pytorch, there's a null somewhere it shouldn't be:
https://github.com/volkswagenfeature/minimalTorchRocm/commit/acf99457e810777a8316c26e69a0b281f0c0945e

Now nix run fails with

warning: Git tree '/home/tristan/Projects/nixos/minimal-replication/minimalTorchRocm' is dirty
error:
       … while calling the 'derivationStrict' builtin

         at /builtin/derivation.nix:9:12: (source not available)

       … while evaluating derivation 'python3-3.12.4-env'
         whose name attribute is located at /nix/store/qxf6anli54ij0q1sdlnlgx9hyl658a4v-source/pkgs/stdenv/generic/make-derivation.nix:334:7

       … while evaluating attribute 'passAsFile' of derivation 'python3-3.12.4-env'

         at /nix/store/qxf6anli54ij0q1sdlnlgx9hyl658a4v-source/pkgs/build-support/trivial-builders/default.nix:69:9:

           68|         inherit buildCommand name;
           69|         passAsFile = [ "buildCommand" ]
             |         ^
           70|           ++ (derivationArgs.passAsFile or [ ]);

       (stack trace truncated; use '--show-trace' to show the full trace)

       error: value is null while a set was expected

Hi, all. I'm having an issue trying to get PySide6 build. The curl: (28) Operation too slow appears consistently regardless of network stability, and preferWheels = true doesn't solve the problem.

The following is a minimum reproducer:

pyproject.toml

[tool.poetry]
name = "test-poetry2nix-pyside6"
version = "0.1.0"
description = ""
authors = ["Your Name <you@example.com>"]
readme = "README.md"
package-mode = false

[tool.poetry.dependencies]
python = ">=3.11, <3.13"
PySide6 = "^6.7.2"


[build-system]
requires = ["poetry-core"]
build-backend = "poetry.core.masonry.api"

flake.nix

{
  inputs.poetry2nix.url = "github:nix-community/poetry2nix";
  inputs.nixpkgs.follows = "poetry2nix/nixpkgs";

  outputs = { self, ...}@inputs:
  let 
    inherit (inputs.nixpkgs) lib;
  in 
  {
    devShells = lib.mapAttrs (system: pkgs:
      let 
        poetry2nix = inputs.poetry2nix.lib.mkPoetry2Nix { inherit pkgs; };
      in 
      {
        default = poetry2nix.mkPoetryEnv {
          projectDir = ./.;
        };
      }
    ) inputs.nixpkgs.legacyPackages;
  };
}

poetry.lock

# This file is automatically @generated by Poetry 1.8.3 and should not be changed by hand.

[[package]]
name = "pyside6"
version = "6.7.2"
description = "Python bindings for the Qt cross-platform application and UI framework"
optional = false
python-versions = "<3.13,>=3.9"
files = [
    {file = "PySide6-6.7.2-cp39-abi3-macosx_11_0_universal2.whl", hash = "sha256:602debef9ec159b0db48f83b38a0e43e2dad3961f7d99f708d98620f04e9112b"},
    {file = "PySide6-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:15e7696a09072ee977f6e6179ab1e48184953df8417bcaa83cfadf0b79747242"},
    {file = "PySide6-6.7.2-cp39-abi3-manylinux_2_31_aarch64.whl", hash = "sha256:6e0acb471535de303f56e3077aa86f53496b4de659b99ecce80520bcee508a63"},
    {file = "PySide6-6.7.2-cp39-abi3-win_amd64.whl", hash = "sha256:f73ae0de77d67f51ca3ce8207b12d3a5fa0107d3d5b6e4aeb3b53ee842b0927a"},
]

[package.dependencies]
PySide6-Addons = "6.7.2"
PySide6-Essentials = "6.7.2"
shiboken6 = "6.7.2"

[[package]]
name = "pyside6-addons"
version = "6.7.2"
description = "Python bindings for the Qt cross-platform application and UI framework (Addons)"
optional = false
python-versions = "<3.13,>=3.9"
files = [
    {file = "PySide6_Addons-6.7.2-cp39-abi3-macosx_11_0_universal2.whl", hash = "sha256:90b995efce61058d995c603ea480a9a3054fe8206739dcbc273fc3b53d40650f"},
    {file = "PySide6_Addons-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:94b9bf6a2a4a7ac671e1776633e50d51326c86f4184f1c6e556f4dd5498fd52a"},
    {file = "PySide6_Addons-6.7.2-cp39-abi3-manylinux_2_31_aarch64.whl", hash = "sha256:22979b1aa09d9cf1d7a86c8a9aa0cb4791d6bd1cc94f96c5b6780c5ef8a9e34e"},
    {file = "PySide6_Addons-6.7.2-cp39-abi3-win_amd64.whl", hash = "sha256:ebf549eb25998665d8e4ec24014fbbd37bebc5ecdcb050b34db1e1c03e1bf81d"},
]

[package.dependencies]
PySide6-Essentials = "6.7.2"
shiboken6 = "6.7.2"

[[package]]
name = "pyside6-essentials"
version = "6.7.2"
description = "Python bindings for the Qt cross-platform application and UI framework (Essentials)"
optional = false
python-versions = "<3.13,>=3.9"
files = [
    {file = "PySide6_Essentials-6.7.2-cp39-abi3-macosx_11_0_universal2.whl", hash = "sha256:4d13666e796ec140ecfb432c4f3d7baef6dfafc11929985a83b22c0025532fb7"},
    {file = "PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:a1a4c09f1e916b9cfe53151fe4a503a6acb1f6621ba28204d1bfe636f80d6780"},
    {file = "PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_31_aarch64.whl", hash = "sha256:9135513e1c4c6e2fbb1e4f9afcb3d42e54708b0d9ed870cb3213ea4874cafa1e"},
    {file = "PySide6_Essentials-6.7.2-cp39-abi3-win_amd64.whl", hash = "sha256:0111d5fa8cf826de3ca9d82fed54726cce116d57f454f88a6467578652032d69"},
]

[package.dependencies]
shiboken6 = "6.7.2"

[[package]]
name = "shiboken6"
version = "6.7.2"
description = "Python/C++ bindings helper module"
optional = false
python-versions = "<3.13,>=3.9"
files = [
    {file = "shiboken6-6.7.2-cp39-abi3-macosx_11_0_universal2.whl", hash = "sha256:50c33ac6317b673a1eb97a9abaafccb162c4ba0c9ca658a8e449c49a8aadc379"},
    {file = "shiboken6-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:70e80737b27cd5d83504b373013b55e70462bd4a27217d919ff9a83958731990"},
    {file = "shiboken6-6.7.2-cp39-abi3-manylinux_2_31_aarch64.whl", hash = "sha256:98bedf9a15f1d8ba1af3e4d1e7527f7946ce36da541e08074fd9dc9ab5ff1adf"},
    {file = "shiboken6-6.7.2-cp39-abi3-win_amd64.whl", hash = "sha256:9024e6afb2af1568ebfc8a5d07e4ff6c8829f40923eeb28901f535463e2b6b65"},
]

[metadata]
lock-version = "2.0"
python-versions = ">=3.11, <3.13"
content-hash = "1e6f7d31cf4eacf82b2e4759e84f5641e32591ba80ef130713ddbfedce2d92c7"

flake.lock

{
  "nodes": {
    "flake-utils": {
      "inputs": {
        "systems": "systems"
      },
      "locked": {
        "lastModified": 1710146030,
        "narHash": "sha256-SZ5L6eA7HJ/nmkzGG7/ISclqe6oZdOZTNoesiInkXPQ=",
        "owner": "numtide",
        "repo": "flake-utils",
        "rev": "b1d9ab70662946ef0850d488da1c9019f3a9752a",
        "type": "github"
      },
      "original": {
        "owner": "numtide",
        "repo": "flake-utils",
        "type": "github"
      }
    },
    "nix-github-actions": {
      "inputs": {
        "nixpkgs": [
          "poetry2nix",
          "nixpkgs"
        ]
      },
      "locked": {
        "lastModified": 1703863825,
        "narHash": "sha256-rXwqjtwiGKJheXB43ybM8NwWB8rO2dSRrEqes0S7F5Y=",
        "owner": "nix-community",
        "repo": "nix-github-actions",
        "rev": "5163432afc817cf8bd1f031418d1869e4c9d5547",
        "type": "github"
      },
      "original": {
        "owner": "nix-community",
        "repo": "nix-github-actions",
        "type": "github"
      }
    },
    "nixpkgs": {
      "locked": {
        "lastModified": 1719763542,
        "narHash": "sha256-mXkOj9sJ0f69Nkc2dGGOWtof9d1YNY8Le/Hia3RN+8Q=",
        "owner": "NixOS",
        "repo": "nixpkgs",
        "rev": "e6cdd8a11b26b4d60593733106042141756b54a3",
        "type": "github"
      },
      "original": {
        "owner": "NixOS",
        "ref": "nixos-unstable-small",
        "repo": "nixpkgs",
        "type": "github"
      }
    },
    "poetry2nix": {
      "inputs": {
        "flake-utils": "flake-utils",
        "nix-github-actions": "nix-github-actions",
        "nixpkgs": "nixpkgs",
        "systems": "systems_2",
        "treefmt-nix": "treefmt-nix"
      },
      "locked": {
        "lastModified": 1723512448,
        "narHash": "sha256-VSTtxGKre1p6zd6ACuBmfDcR+BT9+ml8Y3KrSbfGFYU=",
        "owner": "nix-community",
        "repo": "poetry2nix",
        "rev": "ed52f844c4dd04dde45550c3189529854384124e",
        "type": "github"
      },
      "original": {
        "owner": "nix-community",
        "repo": "poetry2nix",
        "type": "github"
      }
    },
    "root": {
      "inputs": {
        "nixpkgs": [
          "poetry2nix",
          "nixpkgs"
        ],
        "poetry2nix": "poetry2nix"
      }
    },
    "systems": {
      "locked": {
        "lastModified": 1681028828,
        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
        "owner": "nix-systems",
        "repo": "default",
        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
        "type": "github"
      },
      "original": {
        "owner": "nix-systems",
        "repo": "default",
        "type": "github"
      }
    },
    "systems_2": {
      "locked": {
        "lastModified": 1681028828,
        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
        "owner": "nix-systems",
        "repo": "default",
        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
        "type": "github"
      },
      "original": {
        "id": "systems",
        "type": "indirect"
      }
    },
    "treefmt-nix": {
      "inputs": {
        "nixpkgs": [
          "poetry2nix",
          "nixpkgs"
        ]
      },
      "locked": {
        "lastModified": 1719749022,
        "narHash": "sha256-ddPKHcqaKCIFSFc/cvxS14goUhCOAwsM1PbMr0ZtHMg=",
        "owner": "numtide",
        "repo": "treefmt-nix",
        "rev": "8df5ff62195d4e67e2264df0b7f5e8c9995fd0bd",
        "type": "github"
      },
      "original": {
        "owner": "numtide",
        "repo": "treefmt-nix",
        "type": "github"
      }
    }
  },
  "root": "root",
  "version": 7
}

Placing the four files in the same directory, run with nix develop path:., and we'll see the following error:

❯ nix develop path:.
[2/3/9 built, 100 copied (83.7/84.1 MiB), 11.1 MiB DL] building PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl: ################error: builder for '/nix/store/arr8jy9wij62fizax32y8pk91qvxmfd5-PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl.drv' failed with exit code 28;
       last 10 log lines:
       > curl: (22) The requested URL returned error: 404                         # ##
       >
       > Predicted URL 'https://files.pythonhosted.org/packages/wheel/p/pyside6-essentials/PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl' failed, querying pypi.org
       > ######################################################################## 100.0%
       > ##############                                                            20.5%curl: (28) Operation too slow. Less than 1 bytes/sec transferred the last 5 seconds
       > Warning: Problem : timeout. Will retry in 1 seconds. 2 retries left.
       > curl: (28) Operation too slow. Less than 1 bytes/sec transferred the last 5 seconds
       > Warning: Problem : timeout. Will retry in 2 seconds. 1 retries left.
       > curl: (28) Operation too slow. Less than 1 bytes/sec transferred the last 5 seconds
       >
       For full logs, run 'nix log /nix/store/arr8jy9wij62fizax32y8pk91qvxmfd5-PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl.drv'.
error: 1 dependencies of derivation '/nix/store/ad5hvyvnn7xhirc99zc6dn2qvrkz343m-python3.11-pyside6-essentials-6.7.2.drv' failed to build
error: 1 dependencies of derivation '/nix/store/yck7n1xjy6j24qv88f0qsg6bqykbzj32-python3-3.11.9-env-env.drv' failed to build

Here is the result of nix log /nix/store/arr8jy9wij62fizax32y8pk91qvxmfd5-PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl.drv^*:

Trying to fetch with predicted URL: https://files.pythonhosted.org/packages/wheel/p/pyside6-essentials/PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl
#=#=#                                                                          
##O#-#                                                                         
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-=O=-                                            #    #     #   #              
-=O=-                                              #     #    #   #            
-=O=-                                                #     #   #    #          
-=O=-                                                  #     #   #   #         
-=O=-                                                     #    #   #   #       
-=O=-                                                       #   #   #   #      
-=O=-                                                         #   #   #  #     
-=O=-                                                          #    #  #  #    
-=O=-                                                            #   #  #  #   
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-=O=-                                                                 #  # ##  
-=O=-                                                                  #  # #  
-=O=-                                                                   #  ### 
-=O=-                                                                    # ##  
curl: (22) The requested URL returned error: 404

Predicted URL 'https://files.pythonhosted.org/packages/wheel/p/pyside6-essentials/PySide6_Essentials-6.7.2-cp39-abi3-manylinux_2_28_x86_64.whl' failed, querying pypi.org
#=#=#                                                                          

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In reply to @truh:matrix.org
maybe the problem is that your source for torch only has wheels and no source tarball

I know nix is a source-first distro, but is that what's causing my issue? On line 35 in flake.nix at the link you can see that I don't have a SHA hash yet. I don't have a SHA hash yet because the flake halts execution well before it reaches the stage where it cares whether it has received source code or a wheel.

As per your advice, I tried following the recommendations at https://nixos.wiki/wiki/Packaging/Python#install_binary_release in this commit. It did not fix my issue. I'm not sure I did it right, could you provide more details?