diff --git a/lib/default.nix b/lib/default.nix
index e1ab88473..b48b4582e 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -15,6 +15,7 @@ in
   buildClan = import ./build-clan { inherit lib nixpkgs clan-core; };
   facts = import ./facts.nix { inherit lib; };
   inventory = import ./inventory { inherit lib clan-core; };
+  values = import ./values { inherit lib; };
   jsonschema = import ./jsonschema { inherit lib; };
   modules = import ./frontmatter {
     inherit lib;
diff --git a/lib/flake-module.nix b/lib/flake-module.nix
index e9ab69a54..ccfdf3151 100644
--- a/lib/flake-module.nix
+++ b/lib/flake-module.nix
@@ -9,6 +9,7 @@
     ./jsonschema/flake-module.nix
     ./inventory/flake-module.nix
     ./build-clan/flake-module.nix
+    ./values/flake-module.nix
   ];
   flake.lib = import ./default.nix {
     inherit lib inputs;
diff --git a/lib/values/default.nix b/lib/values/default.nix
new file mode 100644
index 000000000..05dcdebe1
--- /dev/null
+++ b/lib/values/default.nix
@@ -0,0 +1,90 @@
+{
+  lib ? import <nixpkgs/lib>,
+}:
+let
+  filterOptions = lib.filterAttrs (
+    name: _:
+    !builtins.elem name [
+      "_module"
+      "_freeformOptions"
+    ]
+  );
+
+  getPrios =
+    {
+      options,
+    }:
+    let
+      filteredOptions = filterOptions options;
+    in
+    lib.mapAttrs (
+      _: opt:
+      let
+        prio = {
+          __prio = opt.highestPrio;
+        };
+        subOptions = opt.type.getSubOptions opt.loc;
+
+        attrDefinitions = (lib.modules.mergeAttrDefinitionsWithPrio opt);
+        zipDefs = builtins.zipAttrsWith (_ns: vs: vs);
+        defs = zipDefs opt.definitions;
+
+        prioPerValue =
+          { type, defs }:
+          lib.mapAttrs (
+            attrName: prioSet:
+            let
+              # Evaluate the submodule
+              options = filterOptions subOptions;
+              modules = (
+                [
+                  { inherit options; }
+                ]
+                ++ map (config: { inherit config; }) defs.${attrName}
+              );
+              submoduleEval = lib.evalModules {
+                inherit modules;
+              };
+            in
+            (lib.optionalAttrs (prioSet ? highestPrio) {
+              __prio = prioSet.highestPrio;
+              # inherit defs options;
+            })
+            // (
+              if type.nestedTypes.elemType.name == "submodule" then
+                getPrios { options = submoduleEval.options; }
+              else
+                # Nested attrsOf
+                (lib.optionalAttrs (type.nestedTypes.elemType.name == "attrsOf") (
+                  prioPerValue {
+                    type = type.nestedTypes.elemType;
+                    defs = zipDefs defs.${attrName};
+                  } prioSet.value
+                ))
+            )
+          );
+
+        attributePrios = prioPerValue {
+          type = opt.type;
+          inherit defs;
+        } attrDefinitions;
+      in
+      if opt ? type && opt.type.name == "submodule" then
+        prio // (getPrios { options = subOptions; })
+      else if opt ? type && opt.type.name == "attrsOf" then
+        #   prio // attributePrios
+        # else if
+        #   opt ? type && opt.type.name == "attrsOf" && opt.type.nestedTypes.elemType.name == "attrsOf"
+        # then
+        #   prio // attributePrios
+        # else if opt ? type && opt.type.name == "attrsOf" then
+        prio // attributePrios
+      else if opt ? type && opt._type == "option" then
+        prio
+      else
+        getPrios { options = opt; }
+    ) filteredOptions;
+in
+{
+  inherit getPrios;
+}
diff --git a/lib/values/flake-module.nix b/lib/values/flake-module.nix
new file mode 100644
index 000000000..db60f92c5
--- /dev/null
+++ b/lib/values/flake-module.nix
@@ -0,0 +1,24 @@
+{ self, inputs, ... }:
+let
+  inputOverrides = builtins.concatStringsSep " " (
+    builtins.map (input: " --override-input ${input} ${inputs.${input}}") (builtins.attrNames inputs)
+  );
+in
+{
+  perSystem =
+    { pkgs, system, ... }:
+    {
+      checks = {
+        lib-values-eval = pkgs.runCommand "tests" { nativeBuildInputs = [ pkgs.nix-unit ]; } ''
+          export HOME="$(realpath .)"
+
+          nix-unit --eval-store "$HOME" \
+            --extra-experimental-features flakes \
+            ${inputOverrides} \
+            --flake ${self}#legacyPackages.${system}.evalTests-inventory
+
+          touch $out
+        '';
+      };
+    };
+}
diff --git a/lib/values/test.nix b/lib/values/test.nix
new file mode 100644
index 000000000..b18c85179
--- /dev/null
+++ b/lib/values/test.nix
@@ -0,0 +1,211 @@
+# tests for the nixos options to jsonschema converter
+# run these tests via `nix-unit ./test.nix`
+{
+  lib ? (import <nixpkgs> { }).lib,
+  slib ? (import ./. { inherit lib; }),
+}:
+let
+  eval =
+    modules:
+    let
+      evaledConfig = lib.evalModules {
+        inherit modules;
+      };
+    in
+    evaledConfig;
+in
+{
+  test_default = {
+    expr = slib.getPrios {
+      options =
+        (eval [
+          {
+            options.foo.bar = lib.mkOption {
+              type = lib.types.bool;
+              description = "Test Description";
+              default = true;
+            };
+          }
+        ]).options;
+    };
+    expected = {
+      foo.bar = {
+        __prio = 1500;
+      };
+    };
+  };
+  test_no_default = {
+    expr = slib.getPrios {
+      options =
+        (eval [
+          {
+            options.foo.bar = lib.mkOption {
+              type = lib.types.bool;
+            };
+          }
+        ]).options;
+    };
+    expected = {
+      foo.bar = {
+        __prio = 9999;
+      };
+    };
+  };
+
+  test_submodule = {
+    expr = slib.getPrios {
+      options =
+        (eval [
+          {
+            options.foo = lib.mkOption {
+              type = lib.types.submodule {
+                options = {
+                  bar = lib.mkOption {
+                    type = lib.types.bool;
+                  };
+                };
+              };
+            };
+          }
+        ]).options;
+    };
+    expected = {
+      foo = {
+        # Prio of the submodule itself
+        __prio = 9999;
+
+        # Prio of the bar option within the submodule
+        bar.__prio = 9999;
+      };
+    };
+  };
+
+  # TODO(@hsjobeki): Cover this edge case
+  # test_freeform =
+  #   let
+  #     evaluated = (
+  #       eval [
+  #         {
+  #           freeformType = with lib.types; attrsOf (int);
+  #           options = {
+  #             foo = lib.mkOption {
+  #               type = lib.types.int;
+  #               default = 0;
+  #             };
+  #           };
+  #         }
+  #         {
+  #           bar = lib.mkForce 123;
+  #           baz = 1;
+  #         }
+  #         {
+  #           bar = 10;
+  #         }
+  #       ]
+  #     );
+  #   in
+  #   {
+  #     inherit evaluated;
+  #     expr = slib.getPrios {
+  #       options = evaluated.options;
+  #     };
+  #     expected = {
+  #     };
+  #   };
+
+  test_attrsOf_submodule =
+    let
+      evaluated = eval [
+        {
+          options.foo = lib.mkOption {
+            type = lib.types.attrsOf (
+              lib.types.submodule {
+                options = {
+                  bar = lib.mkOption {
+                    type = lib.types.int;
+                    default = 0;
+                  };
+                };
+              }
+            );
+          };
+          config.foo = {
+            "nested" = {
+              "bar" = 2; # <- 100 prio ?
+            };
+            "other" = {
+              "bar" = lib.mkForce 2; # <- 50 prio ?
+            };
+          };
+        }
+      ];
+    in
+    {
+      expr = slib.getPrios { options = evaluated.options; };
+      expected = {
+        foo.__prio = 100;
+
+        foo.nested.__prio = 100;
+        foo.other.__prio = 100;
+
+        foo.nested.bar.__prio = 100;
+        foo.other.bar.__prio = 50;
+      };
+    };
+  test_attrsOf_attrsOf_submodule =
+    let
+      evaluated = eval [
+        {
+          options.foo = lib.mkOption {
+            type = lib.types.attrsOf (
+              lib.types.attrsOf (
+                lib.types.submodule {
+                  options = {
+                    bar = lib.mkOption {
+                      type = lib.types.int;
+                      default = 0;
+                    };
+                  };
+                }
+              )
+            );
+          };
+          config.foo = {
+            a.b = {
+              bar = 1;
+            };
+            a.c = {
+              bar = 1;
+            };
+            x.y = {
+              bar = 1;
+            };
+            x.z = {
+              bar = 1;
+            };
+          };
+        }
+      ];
+    in
+    {
+      inherit evaluated;
+      expr = slib.getPrios { options = evaluated.options; };
+      expected = {
+        foo.__prio = 100;
+
+        # Sub A
+        foo.a.__prio = 100;
+        # a.b doesnt have a prio
+        # a.c doesnt have a prio
+        foo.a.b.bar.__prio = 100;
+        foo.a.c.bar.__prio = 100;
+
+        # Sub X
+        foo.x.__prio = 100;
+        # x.y doesnt have a prio
+        # x.z doesnt have a prio
+        foo.x.y.bar.__prio = 100;
+        foo.x.z.bar.__prio = 100;
+      };
+    };
+}