Look for projectArgs.nix

Author: hamishmack

hix/default.nix

@@ -103,7 +103,7 @@ let
           chmod +w $FLAKE/flake.nix
         fi
         if [ "$projectArgs" != "" ]; then
-          printf %s "$projectArgs" > "$HIX_TMPDIR/default.nix"
+          printf %s "$projectArgs" > "$HIX_TMPDIR/projectArgs.nix"
         fi
         nix $cmd "''${args[@]}"
         ;;

hix/empty-set/default.nix

@@ -5,7 +5,7 @@
   inputs.haskellNix.url = "github:input-output-hk/haskell.nix";
   inputs.nixpkgs.follows = "haskellNix/nixpkgs-unstable";
   inputs.flake-utils.url = "github:numtide/flake-utils";
-  inputs.projectArgs.url = "github:input-output-hk/haskell.nix?dir=hix/empty-set";
+  inputs.projectArgs.url = "github:input-output-hk/empty-flake";
   inputs.projectArgs.flake = false;
   inputs.src.flake = false;
   outputs = { self, src, nixpkgs, flake-utils, haskellNix, projectArgs }:
@@ -16,7 +16,10 @@
           hixProject =
             final.haskell-nix.hix.project ({
               inherit src;
-            } // import projectArgs);
+            } // (
+              if builtins.pathExists (projectArgs + "/projectArgs.nix")
+                then import (projectArgs + "/projectArgs.nix")
+                else {}));
         })
       ];
       pkgs = import nixpkgs { inherit system overlays; inherit (haskellNix) config; };