li in PredVP

flake.nix

@@ -0,0 +1,55 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    # gf.url = "github:anka-213/cclaw-nix-stuff/nix-flakes";
+    sydpkgs.url = "git+https://git.deertopia.net/msyds/sydpkgs";
+  };
+
+  outputs = { self, nixpkgs, sydpkgs, ... }@inputs:
+    let
+      supportedSystems = [
+        "aarch64-darwin"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "x86_64-linux"
+      ];
+
+      each-system = f: nixpkgs.lib.genAttrs supportedSystems (system: f rec {
+	pkgs = import nixpkgs {
+	  inherit system;
+	  overlays = [
+	    # (final: prev: { inherit (gf.packages.${system}) gf-core; })
+	    sydpkgs.overlays.default
+	  ];
+	};
+	inherit (pkgs) lib;
+        inherit system;
+      });
+    in {
+      # Exposed as a REPL convenience.
+      _pkgs = each-system ({ pkgs, ... }: pkgs);
+
+      packages = each-system ({ pkgs, ... }: {
+	default = pkgs.callPackage ./package.nix {};
+      });
+
+      devShells = each-system ({ pkgs, system, ... }:
+        let
+	  gf-lsp = import
+	    (pkgs.fetchzip {
+	      url = "https://github.com/anka-213/gf-lsp/archive/refs/tags/1.0.6.0.tar.gz";
+	      hash = "sha256-UAI2qUslzLOWYjTirZJ0y4DZbkPZnVXTY0XtFO8+Rks=";
+	    }) {inherit system;};
+	in {
+	  default = pkgs.mkShell {
+	    inputsFrom = [ self.packages.${system}.default ];
+	    packages = [
+	      gf-lsp.gf-lsp
+	      pkgs.gftest
+	      pkgs.graphviz
+	      pkgs.imagemagick
+	    ];
+	  };
+	});
+    };
+}