Improve nix build

.gitignore

@@ -2,3 +2,4 @@
 /.direnv
 *.mgc
 *.typ
+/result

flake.nix

@@ -18,9 +18,10 @@
         version = "0.1.0";
 
         src = ./.;
-        cargoHash = lib.fakeHash;
+        cargoHash = "sha256-2zRYcP0Zz9yqkUbrElq5g098tsPizqEl1l8HKQwx9pI=";
 
-        buildInputs = [pkgs.zathuraPkgs.zathura_core pkgs.girara pkgs.cairo pkgs.pkg-config];
+        buildInputs = [pkgs.zathuraPkgs.zathura_core pkgs.girara pkgs.cairo pkgs.openssl];
+        nativeBuildInputs = [pkgs.perl pkgs.pkg-config];
 
         # From https://hoverbear.org/blog/rust-bindgen-in-nix/
         LIBCLANG_PATH = "${pkgs.llvmPackages.libclang.lib}/lib";