WIP: added QC flake

flake.nix

@@ -86,17 +86,18 @@
       };
 
       templates.default = {
-        path = ./template;
-        description = "NixOS-QChem template flake with reasonable defaults and editable configuration";
+        path = ./template/qc;
+        description = "Quantum Chemistry flake";
         welcomeText = ''
           Welcome to the NixOS-QChem template flake with optimised packages for computational chemistry!
 
           If you use this flake and/or packages from NixOS-QChem, please cite https://doi.org/10.1002/qua.26872 in your work!
 
           The flake aims for reasonable defaults but can be customised to your needs.
           Look for "EDITME" tokens in the flake.nix to find places where you can customise the flake,
-          e.g. by adding or removing unfree packages, changing CPU architecture specific optimisations,
-          or constructing a Python environment suiting your requirements.
+
+          Note, the "nix" and "calcs" subdirectories: to avoid flooding the Nix storen with large files,
+          run your calculations in the "calcs" directory and refer to the "flake" in the "nix" directory.
         '';
       };
     };

lib.nix

@@ -24,4 +24,9 @@
     lib.mapAttrs (pkg: _: callPackage (dir + "/${pkg}/package.nix") {})
     (lib.filterAttrs (_: type: type == "directory") (builtins.readDir dir));
 
+  buildEnvMpi = symlinkJoin: input:
+    symlinkJoin {
+      inherit (input) name;
+      paths = lib.flatten (map(x: if x ? passthru.mpi then [ x x.passthru.mpi ] else x) input.paths);
+    };
 }

overlay.nix

@@ -39,6 +39,7 @@ let
 
         inherit callPackage;
         inherit aggressiveStdenv;
+        inherit qlib;
 
         #
         # Upstream overrides

template/qc/nix/flake.nix

@@ -0,0 +1,86 @@
+{
+  description = "A flake for computational chemistry, based on NixOS-QChem";
+
+  inputs = {
+    qchem.url = "github:nix-qchem/nixos-qchem";
+  };
+
+  nixConfig = {
+    extra-substituters = [ "https://nix-qchem.cachix.org" ];
+    extra-trusted-public-keys = [ "nix-qchem.cachix.org-1:ZjRh1PosWRj7qf3eukj4IxjhyXx6ZwJbXvvFk3o3Eos=" ];
+    allow-import-from-derivation = "true";
+  };
+
+  outputs = { self, qchem }:
+    let
+      # EDITME
+      # Disables unfree packages by default to avoid non-building packages, that
+      # use unfree ones as dependencies, e.g. Pysisyphus or SHARC.
+      # Comment out lines to enable the respective package.
+      filterUnfree = final: prev: {
+        qchem = prev.qchem // {
+          turbomole = null;
+          cefine = null;
+          cfour = null;
+          gamess-us = null;
+          gaussian = null;
+          gaussview = null;
+          mrcc = null;
+          orca = null;
+          vmd = null;
+          mesa-qc = null;
+          mcdth = null;
+          nixGL = null;
+        };
+      };
+
+      system = "x86_64-linux";
+      pkgs = import qchem.inputs.nixpkgs {
+        inherit system;
+        overlays = [ qchem.overlays.default filterUnfree ];
+        config = {
+          allowUnfree = true;
+
+          # EDITME
+          qchem-config = {
+            # Set to false if node does not support AVX2
+            optAVX = true;
+
+            # Set to an installation path of Gaussian outside the Nix
+            # store if you have one. Should have a directory structure like this:
+            #   "${optpath}/gaussian/g16/"
+            #optpath = "/opt";
+
+            # Set and uncomment if you have a MolPro license key.
+            #licMolpro = "XXXX-XXXX-XXXX-XXXX";
+
+            # Set and uncomment if you have a Q-Chem license key file.
+            #licQChem = "/path/to/qchem.lic";
+
+            # Uncomment if you have a server from which non-redistributable
+            # software can be downloaded
+            #srcurl = "http://myserver/nix-src/";
+          };
+        };
+      };
+
+      filterDrvs = pkgSet:
+        pkgs.lib.filterAttrs (_: val: pkgs.lib.isDerivation val)
+          pkgSet;
+    in
+    {
+      # EDITME
+      # Add packages to the default package as you wish
+      packages."${system}" = (filterDrvs pkgs.qchem) // {
+        default = pkgs.qchem.qlib.buildEnvMpi pkgs.symlinkJoin {
+          name = "quantum-chemistry";
+          paths = [
+            # put a list of packages here. e.g.:
+            #pkgs.qchem.orca
+            #pkgs.qchem.psi4
+            #pkgs.gnuplot
+          ];
+        };
+      };
+    };
+}