openLCA on NixOS

A Nix flake to install and run the openLCA - a free, open source software for Life Cycle Assessment (LCA) and sustainability analysis on NixOS.

openLCA ships as a pre-built Eclipse RCP app bundled with its own JRE, Intel MKL, and SWT bindings. On standard distros, these "just work." On NixOS, they break. Because NixOS lacks a global /lib, bundled binaries can't find dependencies. This flake fixes that by:

• Patching ELF binaries for the Nix store.
• Wrapping the app with the correct LD_LIBRARY_PATH.
• Fixing WebKitGTK so the internal browser actually renders. (Somewhat Works)

• NixOS with flakes enabled
• x86_64 architecture
• nixpkgs.config.allowUnfree = true (required for Intel MKL)

In your /etc/nixos/flake.nix, add openlca-nix as an input:

inputs = {
  nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
  # ... your other inputs ...

  openlca-nix = {
    url = "github:peaceofsense/openlca-nix";
    inputs.nixpkgs.follows = "nixpkgs";
  };
};

Then pass it into your NixOS configuration and add the package:

outputs = { self, nixpkgs, openlca-nix, ... }@inputs:
{
  nixosConfigurations.yourhostname = nixpkgs.lib.nixosSystem {
    system = "x86_64-linux";
    modules = [
      ./configuration.nix
      {
        nixpkgs.config.allowUnfree = true;
        environment.systemPackages = [
          openlca-nix.packages.${system}.default
        ];
      }
    ];
  };
};

Then rebuild your system:

sudo nixos-rebuild switch --flake /etc/nixos#yourhostname

nix run github:peaceofsense/openlca-nix

nix profile install github:peaceofsense/openlca-nix

After installation, you can launch openLCA from your application menu or run:

openlca

On first launch, openLCA will create a workspace directory at ~/openLCA-data-1.4.

When GreenDelta releases a new version:

1. Get the new download URL from openLCA downloads
2. Get the new hash:

   nix-prefetch-url --type sha256 "YOUR_NEW_DOWNLOAD_URL"

3. Update version and the sha256 in flake.nix
4. Commit and push

• GreenDelta for developing and maintaining openLCA
• The NixOS community for autoPatchelfHook and packaging tooling

The Nix packaging code in this repository is released under the MIT License. openLCA itself is licensed under the Mozilla Public License 2.0. Intel MKL is subject to the Intel Simplified Software License.