diff --git a/README.md b/README.md
index 94ebdda4..d31d6c8d 100644
--- a/README.md
+++ b/README.md
@@ -85,39 +85,29 @@ A minimal example of using an existing configuration.nix:
     darwin.inputs.nixpkgs.follows = "nixpkgs";
   };
 
-  outputs = { self, darwin, nixpkgs }: {
+  outputs = inputs@{ self, darwin, nixpkgs }: {
     darwinConfigurations."Johns-MacBook" = darwin.lib.darwinSystem {
-      system = "x86_64-darwin";
       modules = [ ./configuration.nix ];
     };
   };
 }
 ```
 
-Inputs from the flake can also be passed to `darwinSystem`. These inputs are then
+Inputs from the flake can also be passed into `darwinSystem`. These inputs are then
 accessible as an argument `inputs`, similar to `pkgs` and `lib`, inside the configuration.
 
 ```nix
+# in flake.nix
 darwin.lib.darwinSystem {
-  system = "x86_64-darwin";
   modules = [ ./configuration.nix ];
-  inputs = { inherit darwin dotfiles nixpkgs; };
+  specialArgs = { inherit inputs; };
 }
-# in configuration.nix:
-{ pkgs, lib, inputs }:
-# inputs.darwin, inputs.dotfiles, and inputs.nixpkgs can be accessed here
 ```
 
-Alternatively, `specialArgs` could be used:
-
 ```nix
-darwin.lib.darwinSystem {
-  system = "x86_64-darwin";
-  modules = [ ./configuration.nix ];
-  specialArgs = { inherit darwin dotfiles nixpkgs; };
-}
-# in configuration.nix:
-{ pkgs, lib, darwin, dotfiles, nixpkgs }:
+# in configuration.nix
+{ pkgs, lib, inputs }:
+# inputs.self, inputs.darwin, and inputs.nixpkgs can be accessed here
 ```
 
 Since the installer doesn't work with flakes out of the box yet, nix-darwin will need to
diff --git a/default.nix b/default.nix
index 11c686bb..7c7e06b2 100644
--- a/default.nix
+++ b/default.nix
@@ -6,19 +6,16 @@
 }:
 
 let
-  evalConfig = import ./eval-config.nix { inherit lib; };
-
-  eval = evalConfig {
-    inherit system;
-    modules = [ configuration nixpkgsRevisionModule ];
-    inputs = { inherit nixpkgs; };
+  eval = import ./eval-config.nix {
+    inherit lib;
+    modules = [
+      configuration
+      { nixpkgs.source = lib.mkDefault nixpkgs; }
+    ] ++ lib.optional (system != null) {
+      nixpkgs.system = lib.mkDefault system;
+    };
   };
 
-  nixpkgsRevisionModule =
-    if nixpkgs?rev && lib.isString nixpkgs.rev
-    then { system.nixpkgsRevision = nixpkgs.rev; }
-    else { };
-
   # The source code of this repo needed by the [un]installers.
   nix-darwin = lib.cleanSource (
     lib.cleanSourceWith {
diff --git a/eval-config.nix b/eval-config.nix
index 2beb1212..9663849a 100644
--- a/eval-config.nix
+++ b/eval-config.nix
@@ -1,13 +1,5 @@
-{ lib }:
-let
-  nixpkgs-lib = lib;
-in
-
-{ system ? builtins.currentSystem or "x86_64-darwin"
-, pkgs ? null
-, lib ? nixpkgs-lib
+{ lib
 , modules
-, inputs
 , baseModules ? import ./modules/module-list.nix
 , specialArgs ? { }
 , check ? true
@@ -18,26 +10,13 @@ let
     _file = ./eval-config.nix;
     config = {
       _module.args = {
-        inherit baseModules inputs modules;
+        inherit baseModules modules;
       };
     };
   };
 
-  pkgsModule = { config, inputs, ... }: {
-    _file = ./eval-config.nix;
-    config = {
-      _module.args.pkgs = lib.mkIf (pkgs != null) (lib.mkForce pkgs);
-
-      nixpkgs.source = lib.mkDefault inputs.nixpkgs;
-
-      # This permits the configuration to override the passed-in
-      # system.
-      nixpkgs.system = lib.mkDefault system;
-    };
-  };
-
-  eval = lib.evalModules (builtins.removeAttrs args [ "lib" "inputs" "pkgs" "system" ] // {
-    modules = modules ++ [ argsModule pkgsModule ] ++ baseModules;
+  eval = lib.evalModules (builtins.removeAttrs args [ "lib" ] // {
+    modules = modules ++ [ argsModule ] ++ baseModules;
     specialArgs = { modulesPath = builtins.toString ./modules; } // specialArgs;
   });
 in
diff --git a/flake.nix b/flake.nix
index 38056aea..e0c9c7ef 100644
--- a/flake.nix
+++ b/flake.nix
@@ -4,22 +4,36 @@
 
   outputs = { self, nixpkgs }: {
     lib = {
-      # TODO handle multiple architectures.
-      evalConfig = import ./eval-config.nix { inherit (nixpkgs) lib; };
+      evalConfig = import ./eval-config.nix;
 
-      darwinSystem =
-        { modules, inputs ? { }
-        , system ? throw "darwin.lib.darwinSystem now requires 'system' to be passed explicitly"
-        , ...
-        }@args:
-        self.lib.evalConfig (args // {
-          inherit system;
-          inputs = { inherit nixpkgs; darwin = self; } // inputs;
-          modules = modules ++ [ self.darwinModules.flakeOverrides ];
-        });
+      darwinSystem = args@{ modules, ... }: self.lib.evalConfig (
+        { inherit (nixpkgs) lib; }
+        // nixpkgs.lib.optionalAttrs (args ? pkgs) { inherit (args.pkgs) lib; }
+        // builtins.removeAttrs args [ "system" "pkgs" "inputs" ]
+        // {
+          modules = modules
+            ++ nixpkgs.lib.optional (args ? pkgs) ({ lib, ... }: {
+              _module.args.pkgs = lib.mkForce args.pkgs;
+            })
+            # Backwards compatibility shim; TODO: warn?
+            ++ nixpkgs.lib.optional (args ? system) ({ lib, ... }: {
+              nixpkgs.system = lib.mkDefault args.system;
+            })
+            # Backwards compatibility shim; TODO: warn?
+            ++ nixpkgs.lib.optional (args ? inputs) {
+              _module.args.inputs = args.inputs;
+            }
+            ++ [ ({ lib, ... }: {
+              nixpkgs.source = lib.mkDefault nixpkgs;
+
+              system.checks.verifyNixPath = lib.mkDefault false;
+
+              system.darwinVersionSuffix = ".${self.shortRev or "dirty"}";
+              system.darwinRevision = lib.mkIf (self ? rev) self.rev;
+            }) ];
+          });
     };
 
-    darwinModules.flakeOverrides = ./modules/system/flake-overrides.nix;
     darwinModules.hydra = ./modules/examples/hydra.nix;
     darwinModules.lnl = ./modules/examples/lnl.nix;
     darwinModules.ofborg = ./modules/examples/ofborg.nix;
@@ -32,8 +46,10 @@
 
     checks = nixpkgs.lib.genAttrs ["aarch64-darwin" "x86_64-darwin"] (system: let
       simple = self.lib.darwinSystem {
-        inherit system;
-        modules = [ self.darwinModules.simple ];
+        modules = [
+          self.darwinModules.simple
+          { nixpkgs.hostPlatform = system; }
+        ];
       };
     in {
       simple = simple.system;
diff --git a/modules/examples/flake/flake.nix b/modules/examples/flake/flake.nix
index 0ada8524..bacdcf55 100644
--- a/modules/examples/flake/flake.nix
+++ b/modules/examples/flake/flake.nix
@@ -1,9 +1,9 @@
 {
-  description = "Example darwin system flake";
+  description = "Example Darwin system flake";
 
   inputs = {
-    nixpkgs.url = "github:nixos/nixpkgs";
-    darwin.url = "github:lnl7/nix-darwin";
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    darwin.url = "github:LnL7/nix-darwin";
     darwin.inputs.nixpkgs.follows = "nixpkgs";
   };
 
@@ -30,6 +30,9 @@
       # Used for backwards compatibility, please read the changelog before changing.
       # $ darwin-rebuild changelog
       system.stateVersion = 4;
+
+      # The platform the configuration will be used on.
+      nixpkgs.hostPlatform = "x86_64-darwin";
     };
   in
   {
@@ -37,7 +40,6 @@
     # $ darwin-rebuild build --flake .#simple
     darwinConfigurations."simple" = darwin.lib.darwinSystem {
       modules = [ configuration ];
-      system = "x86_64-darwin";
     };
 
     # Expose the package set, including overlays, for convenience.
diff --git a/modules/system/flake-overrides.nix b/modules/system/flake-overrides.nix
deleted file mode 100644
index df3eb168..00000000
--- a/modules/system/flake-overrides.nix
+++ /dev/null
@@ -1,20 +0,0 @@
-{ lib, inputs, ... }:
-
-with lib;
-
-let
-  inherit (inputs) darwin nixpkgs;
-in
-
-{
-  config = {
-    system.checks.verifyNixPath = mkDefault false;
-    system.checks.verifyNixChannels = mkDefault false;
-
-    system.darwinVersionSuffix = ".${darwin.shortRev or "dirty"}";
-    system.darwinRevision = mkIf (darwin ? rev) darwin.rev;
-
-    system.nixpkgsVersionSuffix = ".${substring 0 8 (nixpkgs.lastModifiedDate or nixpkgs.lastModified or "19700101")}.${nixpkgs.shortRev or "dirty"}";
-    system.nixpkgsRevision = mkIf (nixpkgs ? rev) nixpkgs.rev;
-  };
-}