Add nix build to CI

.github/workflows/ci.yml

@@ -12,6 +12,10 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
+      - uses: cachix/install-nix-action@v31
+        with:
+          nix_path: nixpkgs=channel:nixpkgs-unstable
+      - run: nix-channel --update
 
       - name: Install ArrayFire
         run: brew install arrayfire
@@ -33,6 +37,15 @@ jobs:
       - name: Configure
         run: cabal configure --flags="disable-default-paths disable-build-tool-depends" --extra-include-dirs=$(brew --prefix arrayfire)/include --extra-lib-dirs=$(brew --prefix arrayfire)/lib
 
-      - name: Build
-        run: cabal build arrayfire
+      - name: hspec-discover
+        run: nix-shell -p ghc -p cabal-install --keep LD_LIBRARY_PATH --run 'cabal install hspec-discover'
 
+      - name: Build
+        run: nix-shell -p ghc -p cabal-install --keep LD_LIBRARY_PATH --run 'cabal build'
+        env:
+          LD_LIBRARY_PATH: "/opt/arrayfire/lib:/opt/arrayfire/lib64"
+
+      - name: Nix build
+        run: nix build
+        env:
+          LD_LIBRARY_PATH: "/opt/arrayfire/lib:/opt/arrayfire/lib64"

flake.nix

@@ -5,11 +5,6 @@
     nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
     flake-utils.url = "github:numtide/flake-utils";
     nix-filter.url = "github:numtide/nix-filter";
-    arrayfire-nix = {
-      url = "github:twesterhout/arrayfire-nix";
-      inputs.flake-utils.follows = "flake-utils";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
   };
 
   outputs = inputs:
@@ -30,13 +25,47 @@
         ];
       };
 
+      # Build ArrayFire from the official binary installer; avoids freeimage entirely.
+      mkArrayfire = pkgs: pkgs.stdenv.mkDerivation rec {
+        pname = "arrayfire";
+        version = "3.10.0";
+        src = pkgs.fetchurl {
+          url = "https://arrayfire.s3.amazonaws.com/${version}/ArrayFire-v${version}_Linux_x86_64.sh";
+          hash = "sha256-8SibCWnRxts79S6WEHb3skF2TIDl1QnjY6EiohmoIog=";
+        };
+        nativeBuildInputs = [ pkgs.autoPatchelfHook ];
+        buildInputs = with pkgs; [
+          stdenv.cc.cc.lib
+          fftw
+          fftwFloat
+          openblas
+          ocl-icd
+          boost.out
+        ];
+        unpackPhase = "true";
+        installPhase = ''
+          mkdir -p $out
+          bash $src --exclude-subdir --prefix=$out
+        '';
+        meta = {
+          description = "A general-purpose library for parallel and massively-parallel architectures";
+          platforms = [ "x86_64-linux" ];
+        };
+      };
+
+      arrayfire-overlay = self: super: {
+        arrayfire = mkArrayfire self;
+      };
+
       # An overlay that lets us test arrayfire-haskell with different GHC versions
       arrayfire-haskell-overlay = self: super: {
         haskell = super.haskell // {
           packageOverrides = inputs.nixpkgs.lib.composeExtensions super.haskell.packageOverrides
             (hself: hsuper: {
               arrayfire = self.haskell.lib.appendConfigureFlags
-                (hself.callCabal2nix "arrayfire" src { af = self.arrayfire; })
+                (hself.callCabal2nix "arrayfire" src {
+                  af = self.arrayfire;
+                })
                 [ "-f disable-default-paths" ];
             });
         };
@@ -56,8 +85,6 @@
             doctest
             hsc2hs
             hspec-discover
-            # Language servers
-            haskell-language-server
             nil
             # Formatters
             nixpkgs-fmt
@@ -69,7 +96,7 @@
       pkgs-for = system: import inputs.nixpkgs {
         inherit system;
         overlays = [
-          inputs.arrayfire-nix.overlays.default
+          arrayfire-overlay
           arrayfire-haskell-overlay
         ];
       };
@@ -78,7 +105,6 @@
       packages = inputs.flake-utils.lib.eachDefaultSystemMap (system:
         with (pkgs-for system); {
           default = haskellPackages.arrayfire;
-          haskell = haskell.packages;
         });
 
       devShells = inputs.flake-utils.lib.eachDefaultSystemMap (system: {