diff --git a/ChangeLog.md b/ChangeLog.md
index 02182ef..6103b3b 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,26 @@
+
+# 2023-05-30
+
+ - Fix a strictness issue in `perInput`, affecting `inputs'`, `self'`.
+   This has caused infinite recursions and potentially performance issues since
+   the introduction of these module arguments.
+
+# 2023-05-08
+
+ - Add [`importApply`](https://flake.parts/define-module-in-separate-file.html?highlight=importApply#importApply) for bringing variables from the flake scope into module files.
+
+ - Add `mkDeferredModuleOption` as a generic name for the implementation of `mkPerSystemOption`.
+
+# 2023-03-26
+
+ - Add preliminary support for `disabledModules` for modules exposed via the importable `flakeModules` module.
+   This requires a Nixpkgs of 2023-03-09 or newer.
+
+# 2023-01-05
+
+ - Add importable `easyOverlay` module for defining an overlay "easily" by reusing `perSystem`.
+   This is not for consuming overlays.
+
 # 2022-12-25
 
  - Added a new `flake.flakeModules` option so a flake can expose a module
diff --git a/README.md b/README.md
index 98c67f6..7d86a0a 100644
--- a/README.md
+++ b/README.md
@@ -3,12 +3,18 @@
 
 _Core of a distributed framework for writing Nix Flakes._
 
-`flake-parts` provides the options that represent standard flake attributes 
+`flake-parts` provides the options that represent standard flake attributes
 and establishes a way of working with `system`.
 Opinionated features are provided by an ecosystem of modules that you can import.
 
 `flake-parts` _itself_ has the goal to be a minimal mirror of the Nix flake schema.
-Used by itself, it is very lightweight. 
+Used by itself, it is very lightweight.
+
+---
+
+**Documentation**: [flake.parts](https://flake.parts)
+
+---
 
 # Why Modules?
 
@@ -71,14 +77,22 @@ then slide `mkFlake` between your outputs function head and body,
 
 Now you can add the remaining module attributes like in the [the template](./template/default/flake.nix).
 
-# Example
+# Templates
 
 See [the template](./template/default/flake.nix).
 
+# Examples
+
+See the [examples/](./examples) directory.
+
+# Projects using flake-parts
+
+- [nixd](https://github.com/nix-community/nixd/blob/main/flake.nix) (c++)
+- [hyperswitch](https://github.com/juspay/hyperswitch/blob/main/flake.nix) (rust)
+- [argo-workflows](https://github.com/argoproj/argo-workflows/blob/master/dev/nix/flake.nix) (go)
+- [nlp-service](https://github.com/recap-utr/nlp-service/blob/main/flake.nix) (python)
+- [emanote](https://github.com/srid/emanote/blob/master/flake.nix) (haskell)
+
 # Options Reference
 
 See [flake.parts options](https://flake.parts/options/flake-parts.html)
-
-# Documentation
-
-See [flake.parts](https://flake.parts)
diff --git a/all-modules.nix b/all-modules.nix
index 83d2bd0..0a9f38e 100644
--- a/all-modules.nix
+++ b/all-modules.nix
@@ -1,4 +1,3 @@
-{ lib, ... }:
 {
   imports = [
     ./modules/apps.nix
diff --git a/dev/flake-module.nix b/dev/flake-module.nix
index fa77f15..5ac60b9 100644
--- a/dev/flake-module.nix
+++ b/dev/flake-module.nix
@@ -13,7 +13,7 @@
     when.dayOfMonth = 1;
   };
 
-  perSystem = { config, self', inputs', pkgs, ... }: {
+  perSystem = { config, pkgs, ... }: {
 
     devShells.default = pkgs.mkShell {
       nativeBuildInputs = [
@@ -42,7 +42,7 @@
     # for repl exploration / debug
     config.config = config;
     options.mySystem = lib.mkOption { default = config.allSystems.${builtins.currentSystem}; };
-    config.effects = withSystem "x86_64-linux" ({ config, pkgs, hci-effects, ... }: {
+    config.effects = withSystem "x86_64-linux" ({ pkgs, hci-effects, ... }: {
       tests = {
         template = pkgs.callPackage ./tests/template.nix { inherit hci-effects; };
       };
diff --git a/dev/flake.nix b/dev/flake.nix
index b0af470..e6fc8e5 100644
--- a/dev/flake.nix
+++ b/dev/flake.nix
@@ -12,7 +12,7 @@
     hercules-ci-effects.url = "github:hercules-ci/hercules-ci-effects";
   };
 
-  outputs = { self, ... }:
+  outputs = { ... }:
     {
       # The dev tooling is in ./flake-module.nix
       # See comment at `inputs` above.
diff --git a/dev/tests/eval-tests.nix b/dev/tests/eval-tests.nix
index e0dedae..437ee1a 100644
--- a/dev/tests/eval-tests.nix
+++ b/dev/tests/eval-tests.nix
@@ -35,6 +35,18 @@ rec {
       };
     };
 
+  packagesNonStrictInDevShells = mkFlake
+    { inputs.self = packagesNonStrictInDevShells; /* approximation */ }
+    {
+      systems = [ "a" "b" ];
+      perSystem = { system, self', ... }: {
+        packages.hello = pkg system "hello";
+        packages.default = self'.packages.hello;
+        devShells = throw "can't be strict in perSystem.devShells!";
+      };
+      flake.devShells = throw "can't be strict in devShells!";
+    };
+
   easyOverlay = mkFlake
     { inputs.self = { }; }
     {
@@ -148,6 +160,8 @@ rec {
 
     assert flakeModulesDisable.test123 == "option123";
 
+    assert packagesNonStrictInDevShells.packages.a.default == pkg "a" "hello";
+
     ok;
 
   result = runTests "ok";
diff --git a/examples/project-commands/Hello.avdl b/examples/project-commands/Hello.avdl
new file mode 100644
index 0000000..2b3507f
--- /dev/null
+++ b/examples/project-commands/Hello.avdl
@@ -0,0 +1,6 @@
+protocol Hello {
+    record Hello {
+        string message;
+        int timestamp;
+    }
+}
\ No newline at end of file
diff --git a/examples/project-commands/README.md b/examples/project-commands/README.md
new file mode 100644
index 0000000..a75b9d6
--- /dev/null
+++ b/examples/project-commands/README.md
@@ -0,0 +1,42 @@
+# project-commands
+
+> **Warning**
+> If you copy the flake.nix remember to `git add [-N|--intent-to-add] flake.nix`, otherwise it won't work
+
+This example shows how to create scripts for your project, by leveraging [mission-control](https://github.com/Platonic-Systems/mission-control)
+
+This is a **potential** alternative to:
+
+- Using a `Makefile` to manage your project's scripts
+- Using the popular [Scripts To Rule Them All](https://github.com/github/scripts-to-rule-them-all); a naming convention for a `scripts/` directory
+- Using a `bin/` directory
+
+## Explanation
+
+In this example we use the [avro-tools](https://avro.apache.org/) to convert our scripts from `.avdl` to `.avsc`.
+
+You don't need to know anything about avro to understand mission-control and use this example (that's Nix baby 🚀).
+
+When setting up [mission-control](https://github.com/Platonic-Systems/mission-control), we add
+one script called `build`. Because of `wrapperName = "run";`, once we open the shell created by nix,
+the commands will be listed as `run build`.
+
+mission-control depends on flake-root, which also exposes the helpful `$FLAKE_ROOT` variable.
+
+After creating the scripts, we need to pass the newly created scripts to the desired shell, in this example we use the default shell.
+
+## Usage
+
+Run:
+
+```sh
+nix develop
+```
+
+And mission-control will print in the new shell the available commands (you should see only one).
+
+Try running
+
+```sh
+run build
+```
diff --git a/examples/project-commands/flake.lock b/examples/project-commands/flake.lock
new file mode 100644
index 0000000..6179e83
--- /dev/null
+++ b/examples/project-commands/flake.lock
@@ -0,0 +1,95 @@
+{
+  "nodes": {
+    "flake-parts": {
+      "inputs": {
+        "nixpkgs-lib": "nixpkgs-lib"
+      },
+      "locked": {
+        "lastModified": 1685662779,
+        "narHash": "sha256-cKDDciXGpMEjP1n6HlzKinN0H+oLmNpgeCTzYnsA2po=",
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "rev": "71fb97f0d875fd4de4994dfb849f2c75e17eb6c3",
+        "type": "github"
+      },
+      "original": {
+        "id": "flake-parts",
+        "type": "indirect"
+      }
+    },
+    "flake-root": {
+      "locked": {
+        "lastModified": 1680964220,
+        "narHash": "sha256-dIdTYcf+KW9a4pKHsEbddvLVSfR1yiAJynzg2x0nfWg=",
+        "owner": "srid",
+        "repo": "flake-root",
+        "rev": "f1c0b93d05bdbea6c011136ba1a135c80c5b326c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "srid",
+        "repo": "flake-root",
+        "type": "github"
+      }
+    },
+    "mission-control": {
+      "locked": {
+        "lastModified": 1683658484,
+        "narHash": "sha256-JkGnWyYZxOnyOhztrxLSqaod6+O/3rRypq0dAqA/zn0=",
+        "owner": "Platonic-Systems",
+        "repo": "mission-control",
+        "rev": "a0c93bd764a3c25e6999397e9f5f119c1b124e38",
+        "type": "github"
+      },
+      "original": {
+        "owner": "Platonic-Systems",
+        "repo": "mission-control",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1687502512,
+        "narHash": "sha256-dBL/01TayOSZYxtY4cMXuNCBk8UMLoqRZA+94xiFpJA=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "3ae20aa58a6c0d1ca95c9b11f59a2d12eebc511f",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-lib": {
+      "locked": {
+        "dir": "lib",
+        "lastModified": 1685564631,
+        "narHash": "sha256-8ywr3AkblY4++3lIVxmrWZFzac7+f32ZEhH/A8pNscI=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "4f53efe34b3a8877ac923b9350c874e3dcd5dc0a",
+        "type": "github"
+      },
+      "original": {
+        "dir": "lib",
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-parts": "flake-parts",
+        "flake-root": "flake-root",
+        "mission-control": "mission-control",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/examples/project-commands/flake.nix b/examples/project-commands/flake.nix
new file mode 100644
index 0000000..a8e070d
--- /dev/null
+++ b/examples/project-commands/flake.nix
@@ -0,0 +1,37 @@
+{
+  description = "Description for the project";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+
+    mission-control.url = "github:Platonic-Systems/mission-control";
+    flake-root.url = "github:srid/flake-root";
+  };
+
+  outputs = inputs@{ flake-parts, ... }:
+    flake-parts.lib.mkFlake { inherit inputs; } {
+      imports = [
+        inputs.mission-control.flakeModule
+        inputs.flake-root.flakeModule
+      ];
+      systems = [ "x86_64-linux" "aarch64-darwin" "x86_64-darwin" ];
+      perSystem = { config, self', inputs', pkgs, system, ... }: {
+        devShells.default = pkgs.mkShell {
+          nativeBuildInputs = with pkgs; [ avro-tools ];
+          inputsFrom = [ config.mission-control.devShell config.flake-root.devShell ];
+        };
+        mission-control = {
+          wrapperName = "run";
+          scripts = {
+            build = {
+              description = "convert files from .avdl to .avsc";
+              exec = ''
+                avro-tools idl2schemata "$FLAKE_ROOT/Hello.avdl" .
+              '';
+              category = "Development";
+            };
+          };
+        };
+      };
+    };
+}
diff --git a/examples/shell-environments/README.md b/examples/shell-environments/README.md
new file mode 100644
index 0000000..0f72c1c
--- /dev/null
+++ b/examples/shell-environments/README.md
@@ -0,0 +1,55 @@
+# shell-environment
+
+> **Warning**
+> If you copy the flake.nix remember to `git add [-N|--intent-to-add] flake.nix`, otherwise it won't work
+
+This example shows how to create a shell environment which
+includes a diverse set of tools:
+
+```sh
+terraform
+wget
+bat
+nixpkgs-fmt
+```
+
+You can search for more packages in [nix packages](https://search.nixos.org/packages)
+
+## Usage
+
+The [`devShells` option](https://flake.parts/options/flake-parts.html#opt-perSystem.devShells) is used by the following command:
+
+```sh
+nix develop
+```
+
+You can have as many shells as you want, in this [flake.nix](./flake.nix), you also have
+`another_env` which includes `curl`. To open it:
+
+```sh
+nix develop .#another_env
+```
+
+## Troubleshooting
+
+### I get bash instead of my shell
+
+`nix develop` was designed for Nixpkgs stdenv, which uses bash, so that you can troubleshoot a Nix build with it. If you use a different shell, you'll want to get just the variables instead.
+
+There are 3 possible solutions:
+
+First, using [direnv](https://direnv.net/) to manage your dev environments. See [direnv-guide](https://haskell.flake.page/direnv). This is the recommended approach.
+
+Second is a simple-unreliable hack, which is adding a `shellHook` to `devShells`
+
+```nix
+devShells.default = pkgs.mkShell {
+  shellHook = ''
+    exec $SHELL
+  '';
+};
+```
+
+You might get a lot different issues, use it at your own risk.
+
+Lastly, there's `nix print-dev-env` which returns the variables - in case you're feeling adventurous, because this is far from a complete solution. See `nix print-dev-env --help`.
diff --git a/examples/shell-environments/flake.lock b/examples/shell-environments/flake.lock
new file mode 100644
index 0000000..f1371b0
--- /dev/null
+++ b/examples/shell-environments/flake.lock
@@ -0,0 +1,63 @@
+{
+  "nodes": {
+    "flake-parts": {
+      "inputs": {
+        "nixpkgs-lib": "nixpkgs-lib"
+      },
+      "locked": {
+        "lastModified": 1685662779,
+        "narHash": "sha256-cKDDciXGpMEjP1n6HlzKinN0H+oLmNpgeCTzYnsA2po=",
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "rev": "71fb97f0d875fd4de4994dfb849f2c75e17eb6c3",
+        "type": "github"
+      },
+      "original": {
+        "id": "flake-parts",
+        "type": "indirect"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1687412861,
+        "narHash": "sha256-Z/g0wbL68C+mSGerYS2quv9FXQ1RRP082cAC0Bh4vcs=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "e603dc5f061ca1d8a19b3ede6a8cf9c9fcba6cdc",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-lib": {
+      "locked": {
+        "dir": "lib",
+        "lastModified": 1685564631,
+        "narHash": "sha256-8ywr3AkblY4++3lIVxmrWZFzac7+f32ZEhH/A8pNscI=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "4f53efe34b3a8877ac923b9350c874e3dcd5dc0a",
+        "type": "github"
+      },
+      "original": {
+        "dir": "lib",
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-parts": "flake-parts",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/examples/shell-environments/flake.nix b/examples/shell-environments/flake.nix
new file mode 100644
index 0000000..25b4045
--- /dev/null
+++ b/examples/shell-environments/flake.nix
@@ -0,0 +1,22 @@
+{
+  description = "Description for the project";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+  };
+
+  outputs = inputs@{ flake-parts, ... }:
+    flake-parts.lib.mkFlake { inherit inputs; } {
+      systems = [ "x86_64-linux" "aarch64-darwin" "x86_64-darwin" ];
+      perSystem = { config, self', inputs', pkgs, system, ... }: {
+        devShells.default = pkgs.mkShell {
+          nativeBuildInputs = with pkgs; [ terraform wget bat nixpkgs-fmt ];
+        };
+
+        devShells.another_env = pkgs.mkShell {
+          nativeBuildInputs = with pkgs; [ curl ];
+        };
+      };
+
+    };
+}
diff --git a/extras/easyOverlay.nix b/extras/easyOverlay.nix
index a29c890..679afd1 100644
--- a/extras/easyOverlay.nix
+++ b/extras/easyOverlay.nix
@@ -1,4 +1,4 @@
-toplevel@{ config, lib, flake-parts-lib, getSystemIgnoreWarning, ... }:
+toplevel@{ lib, flake-parts-lib, getSystemIgnoreWarning, ... }:
 let
   inherit (flake-parts-lib)
     mkPerSystemOption;
@@ -37,7 +37,7 @@ in
         };
       };
       config = {
-        _module.args.final = lib.mkDefault (pkgs.extend (toplevel.config.flake.overlays.default));
+        _module.args.final = lib.mkDefault (pkgs.extend toplevel.config.flake.overlays.default);
       };
     });
   };
diff --git a/extras/flakeModules.nix b/extras/flakeModules.nix
index d4e0e63..b66ef9c 100644
--- a/extras/flakeModules.nix
+++ b/extras/flakeModules.nix
@@ -1,10 +1,8 @@
-{ config, self, lib, flake-parts-lib, moduleLocation, ... }:
+{ self, lib, flake-parts-lib, moduleLocation, ... }:
 let
   inherit (lib)
-    filterAttrs
     mapAttrs
     mkOption
-    optionalAttrs
     types
     ;
   inherit (flake-parts-lib)
diff --git a/flake.lock b/flake.lock
index 46c8d31..5b3d2cc 100644
--- a/flake.lock
+++ b/flake.lock
@@ -3,11 +3,11 @@
     "nixpkgs-lib": {
       "locked": {
         "dir": "lib",
-        "lastModified": 1682879489,
-        "narHash": "sha256-sASwo8gBt7JDnOOstnps90K1wxmVfyhsTPPNTGBPjjg=",
+        "lastModified": 1688049487,
+        "narHash": "sha256-100g4iaKC9MalDjUW9iN6Jl/OocTDtXdeAj7pEGIRh4=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "da45bf6ec7bbcc5d1e14d3795c025199f28e0de0",
+        "rev": "4bc72cae107788bf3f24f30db2e2f685c9298dc9",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index 5d1447b..8b934f6 100644
--- a/flake.nix
+++ b/flake.nix
@@ -5,8 +5,15 @@
     nixpkgs-lib.url = "github:NixOS/nixpkgs/nixos-unstable?dir=lib";
   };
 
-  outputs = { self, nixpkgs-lib, ... }: {
-    lib = import ./lib.nix { inherit (nixpkgs-lib) lib; };
+  outputs = { nixpkgs-lib, ... }: {
+    lib = import ./lib.nix {
+      inherit (nixpkgs-lib) lib;
+      # Extra info for version check message
+      revInfo =
+        if nixpkgs-lib?rev
+        then " (nixpkgs-lib.rev: ${nixpkgs-lib.rev})"
+        else "";
+    };
     templates = {
       default = {
         path = ./template/default;
diff --git a/lib.nix b/lib.nix
index 102dabb..33f20e4 100644
--- a/lib.nix
+++ b/lib.nix
@@ -1,4 +1,8 @@
-{ lib }:
+{ lib
+  # Optionally a string with extra version info to be included in the error message
+  # in case is lib is out of date. Empty or starts with space.
+, revInfo ? ""
+}:
 let
   inherit (lib)
     mkOption
@@ -28,27 +32,6 @@ let
     then maybeFlake._type == "flake"
     else maybeFlake ? inputs && maybeFlake ? outputs && maybeFlake ? sourceInfo;
 
-  # Polyfill functionTo to make sure it has type merging.
-  # Remove 2022-12
-  functionTo =
-    let sample = types.functionTo lib.types.str;
-    in
-    if sample.functor.wrapped._type or null == "option-type"
-    then types.functionTo
-    else
-      elemType: lib.mkOptionType {
-        name = "functionTo";
-        description = "function that evaluates to a(n) ${elemType.description}";
-        check = lib.isFunction;
-        merge = loc: defs:
-          fnArgs: (lib.mergeDefinitions (loc ++ [ "[function body]" ]) elemType (map (fn: { inherit (fn) file; value = fn.value fnArgs; }) defs)).mergedValue;
-        getSubOptions = prefix: elemType.getSubOptions (prefix ++ [ "[function body]" ]);
-        getSubModules = elemType.getSubModules;
-        substSubModules = m: functionTo (elemType.substSubModules m);
-        functor = (lib.defaultFunctor "functionTo") // { type = functionTo; wrapped = elemType; };
-        nestedTypes.elemType = elemType;
-      };
-
   # Polyfill https://github.com/NixOS/nixpkgs/pull/163617
   deferredModuleWith = lib.deferredModuleWith or (
     attrs@{ staticModules ? [ ] }: mkOptionType {
@@ -219,7 +202,7 @@ let
           } // optionalAttrs (toType != null) {
           type = toType;
         });
-        config = (mkAliasAndWrapDefsWithPriority (setAttrByPath to) fromOpt);
+        config = mkAliasAndWrapDefsWithPriority (setAttrByPath to) fromOpt;
       };
 
     # Helper function for importing while preserving module location. To be added
@@ -231,5 +214,19 @@ let
       lib.setDefaultModuleLocation modulePath (import modulePath staticArgs);
   };
 
+  # A best effort, lenient estimate. Please use a recent nixpkgs lib if you
+  # override it at all.
+  minVersion = "22.05";
+
 in
-flake-parts-lib
+
+if builtins.compareVersions lib.version minVersion < 0
+then
+  abort ''
+    The nixpkgs-lib dependency of flake-parts was overridden but is too old.
+    The minimum supported version of nixpkgs-lib is ${minVersion},
+    but the actual version is ${lib.version}${revInfo}.
+  ''
+else
+
+  flake-parts-lib
diff --git a/modules/apps.nix b/modules/apps.nix
index dcd5b09..0fd5d7c 100644
--- a/modules/apps.nix
+++ b/modules/apps.nix
@@ -1,4 +1,4 @@
-{ config, lib, flake-parts-lib, ... }:
+{ lib, flake-parts-lib, ... }:
 let
   inherit (lib)
     mkOption
@@ -17,11 +17,6 @@ let
   getExe = x:
     "${lib.getBin x}/bin/${x.meta.mainProgram or (throw ''Package ${x.name or ""} does not have meta.mainProgram set, so I don't know how to find the main executable. You can set meta.mainProgram, or pass the full path to executable, e.g. program = "''${pkg}/bin/foo"'')}";
 
-  getBin = x:
-    if !x?outputSpecified || !x.outputSpecified
-    then x.bin or x.out or x
-    else x;
-
   appType = lib.types.submodule {
     options = {
       type = mkOption {
diff --git a/modules/checks.nix b/modules/checks.nix
index d849c65..9e7ceae 100644
--- a/modules/checks.nix
+++ b/modules/checks.nix
@@ -1,4 +1,4 @@
-{ config, lib, flake-parts-lib, ... }:
+{ lib, flake-parts-lib, ... }:
 let
   inherit (lib)
     mkOption
diff --git a/modules/debug.nix b/modules/debug.nix
index 6436010..995f13b 100644
--- a/modules/debug.nix
+++ b/modules/debug.nix
@@ -10,9 +10,6 @@ let
   inherit (flake-parts-lib)
     mkPerSystemOption
     ;
-  inherit (builtins)
-    removeAttrs
-    ;
 
   mkDebugConfig = { config, options, extendModules }: config // {
     inherit config;
diff --git a/modules/devShells.nix b/modules/devShells.nix
index 6521fa8..c0cc6c5 100644
--- a/modules/devShells.nix
+++ b/modules/devShells.nix
@@ -1,8 +1,9 @@
-{ config, lib, flake-parts-lib, ... }:
+{ lib, flake-parts-lib, ... }:
 let
   inherit (lib)
     mkOption
     types
+    literalExpression
     ;
   inherit (flake-parts-lib)
     mkTransposedPerSystemModule
@@ -17,6 +18,13 @@ mkTransposedPerSystemModule {
       An attribute set of packages to be used as shells.
       [`nix develop .#<name>`](https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-develop.html) will run `devShells.<name>`.
     '';
+    example = literalExpression ''
+      {
+        default = pkgs.mkShell {
+          nativeBuildInputs = with pkgs; [ wget bat cargo ];
+        };
+      }
+    '';
   };
   file = ./devShells.nix;
 }
diff --git a/modules/flake.nix b/modules/flake.nix
index 884b2de..012a6c9 100644
--- a/modules/flake.nix
+++ b/modules/flake.nix
@@ -1,10 +1,7 @@
-{ config, lib, ... }:
+{ lib, ... }:
 let
   inherit (lib)
-    filterAttrs
-    mapAttrs
     mkOption
-    optionalAttrs
     types
     ;
 in
diff --git a/modules/formatter.nix b/modules/formatter.nix
index 975e664..838b7cf 100644
--- a/modules/formatter.nix
+++ b/modules/formatter.nix
@@ -24,7 +24,7 @@ in
       };
     };
 
-    perSystem = mkPerSystemOption ({ config, ... }: {
+    perSystem = mkPerSystemOption {
       _file = ./formatter.nix;
       options = {
         formatter = mkOption {
@@ -35,7 +35,7 @@ in
           '';
         };
       };
-    });
+    };
   };
   config = {
     flake.formatter =
diff --git a/modules/legacyPackages.nix b/modules/legacyPackages.nix
index 36df4dd..fb17e14 100644
--- a/modules/legacyPackages.nix
+++ b/modules/legacyPackages.nix
@@ -1,4 +1,4 @@
-{ config, lib, flake-parts-lib, ... }:
+{ lib, flake-parts-lib, ... }:
 let
   inherit (lib)
     mkOption
diff --git a/modules/moduleWithSystem.nix b/modules/moduleWithSystem.nix
index 057399e..e5c7008 100644
--- a/modules/moduleWithSystem.nix
+++ b/modules/moduleWithSystem.nix
@@ -1,4 +1,4 @@
-{ config, lib, withSystem, ... }:
+{ withSystem, ... }:
 {
   config = {
     _module.args = {
diff --git a/modules/nixosConfigurations.nix b/modules/nixosConfigurations.nix
index c2ae8d6..7dc973b 100644
--- a/modules/nixosConfigurations.nix
+++ b/modules/nixosConfigurations.nix
@@ -1,4 +1,4 @@
-{ config, lib, flake-parts-lib, ... }:
+{ lib, flake-parts-lib, ... }:
 let
   inherit (lib)
     mkOption
diff --git a/modules/nixosModules.nix b/modules/nixosModules.nix
index be375bb..6803b78 100644
--- a/modules/nixosModules.nix
+++ b/modules/nixosModules.nix
@@ -1,10 +1,8 @@
-{ config, self, lib, flake-parts-lib, moduleLocation, ... }:
+{ self, lib, flake-parts-lib, moduleLocation, ... }:
 let
   inherit (lib)
-    filterAttrs
     mapAttrs
     mkOption
-    optionalAttrs
     types
     ;
   inherit (flake-parts-lib)
diff --git a/modules/overlays.nix b/modules/overlays.nix
index 86fc457..a09e8f6 100644
--- a/modules/overlays.nix
+++ b/modules/overlays.nix
@@ -1,4 +1,4 @@
-{ config, lib, flake-parts-lib, ... }:
+{ lib, flake-parts-lib, ... }:
 let
   inherit (lib)
     mkOption
@@ -16,7 +16,7 @@ in
         # also update description when done
         type = types.lazyAttrsOf (types.uniq (types.functionTo (types.functionTo (types.lazyAttrsOf types.unspecified))));
         # This eta expansion exists for the sole purpose of making nix flake check happy.
-        apply = lib.mapAttrs (k: f: final: prev: f final prev);
+        apply = lib.mapAttrs (_k: f: final: prev: f final prev);
         default = { };
         example = lib.literalExpression or lib.literalExample ''
           {
diff --git a/modules/packages.nix b/modules/packages.nix
index dcb29eb..20f0071 100644
--- a/modules/packages.nix
+++ b/modules/packages.nix
@@ -1,4 +1,4 @@
-{ config, lib, flake-parts-lib, ... }:
+{ lib, flake-parts-lib, ... }:
 let
   inherit (lib)
     mkOption
diff --git a/modules/transposition.nix b/modules/transposition.nix
index 5ddfcd0..a89b9c8 100644
--- a/modules/transposition.nix
+++ b/modules/transposition.nix
@@ -7,10 +7,6 @@ let
     mkOption
     types
     ;
-  inherit (flake-parts-lib)
-    mkSubmoduleOptions
-    mkPerSystemOption
-    ;
 
   transpositionModule = {
     options = {
@@ -65,12 +61,9 @@ in
       system: flake:
       mapAttrs
         (attrName: attrConfig: flake.${attrName}.${system})
-        (filterAttrs
-          (attrName: attrConfig: flake?${attrName}.${system})
-          config.transposition
-        );
+        config.transposition;
 
-    perSystem = { ... }: {
+    perSystem = {
       options =
         mapAttrs
           (k: v: lib.mkOption { })
diff --git a/modules/withSystem.nix b/modules/withSystem.nix
index c6b0a16..161eece 100644
--- a/modules/withSystem.nix
+++ b/modules/withSystem.nix
@@ -1,8 +1,6 @@
-{ config, lib, flake-parts-lib, self, getSystem, ... }:
+{ lib, flake-parts-lib, getSystem, ... }:
 let
   inherit (lib)
-    genAttrs
-    mapAttrs
     mkOption
     types
     ;
@@ -12,7 +10,7 @@ let
 in
 {
   options = {
-    perSystem = mkPerSystemOption ({ config, options, system, specialArgs, ... }: {
+    perSystem = mkPerSystemOption ({ config, options, specialArgs, ... }: {
       _file = ./perSystem.nix;
       options = {
         allModuleArgs = mkOption {
diff --git a/template/default/flake.nix b/template/default/flake.nix
index ab4bc55..929e34f 100644
--- a/template/default/flake.nix
+++ b/template/default/flake.nix
@@ -14,7 +14,7 @@
         # 3. Add here: foo.flakeModule
 
       ];
-      systems = [ "x86_64-linux" "aarch64-darwin" ];
+      systems = [ "x86_64-linux" "aarch64-linux" "aarch64-darwin" "x86_64-darwin" ];
       perSystem = { config, self', inputs', pkgs, system, ... }: {
         # Per-system attributes can be defined here. The self' and inputs'
         # module parameters provide easy access to attributes of the same