diff --git a/README.md b/README.md
index 7921c79..6ea7ca0 100644
--- a/README.md
+++ b/README.md
@@ -377,7 +377,7 @@ on `pkgs` and consumers of your flake can use the generated `<your-flake>.overla
 				# Optionally place all packages under a namespace when used in an overlay.
 				# Instead of accessing packages with `pkgs.<name>`, your internal packages
 				# will be available at `pkgs.<namespace>.<name>`.
-				overlay-package-namespace = "my-namespace";
+				package-namespace = "my-namespace";
 
 				# You can also pass through external packages or dynamically create new ones
 				# in addition to the ones that `lib` will create from your `packages/` directory.
@@ -1327,7 +1327,7 @@ Type: `Attrs -> Attrs -> [(a -> b -> c)]`
 Usage:
 
 ```nix
-create-overlays-builder { src = ./my-overlays; overlay-package-namespace = "my-packages"; extra-overlays = []; }
+create-overlays-builder { src = ./my-overlays; package-namespace = "my-packages"; extra-overlays = []; }
 ```
 
 Result:
@@ -1348,7 +1348,7 @@ Usage:
 create-overlays {
 	src = ./my-overlays;
 	packages-src = ./my-packages;
-	overlay-package-namespace = "my-namespace";
+	package-namespace = "my-namespace";
 	extra-overlays = {
 		my-example = final: prev: {};
 	};
diff --git a/lib/default.nix b/lib/default.nix
index fd22b10..ee1c6e8 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -8,7 +8,7 @@ user-options:
 let
   user-inputs = user-options.inputs // { src = user-options.src; };
 
-  inherit (core-inputs.nixpkgs.lib) assertMsg fix filterAttrs mergeAttrs fold recursiveUpdate;
+  inherit (core-inputs.nixpkgs.lib) assertMsg fix filterAttrs mergeAttrs fold recursiveUpdate callPackageWith;
 
   # Recursively merge a list of attribute sets.
   # Type: [Attrs] -> Attrs
@@ -87,10 +87,10 @@ let
       attrs = {
         inherit (user-options) inputs;
         snowfall-inputs = core-inputs;
-        lib = merge-shallow [ base-lib user-lib ];
+        lib = merge-shallow [ base-lib { internal = user-lib; } ];
       };
       libs = builtins.map
-        (path: import path attrs)
+        (path: callPackageWith attrs path { })
         user-lib-modules;
     in
     merge-deep libs
@@ -104,6 +104,6 @@ let
   user-inputs-has-self = builtins.elem "self" (builtins.attrNames user-inputs);
   user-inputs-has-src = builtins.elem "src" (builtins.attrNames user-inputs);
 in
- assert (assertMsg (user-inputs-has-self) "Missing attribute `self` for mkLib.");
- assert (assertMsg (user-inputs-has-src) "Missing attribute `src` for mkLib.");
- lib
+assert (assertMsg (user-inputs-has-self) "Missing attribute `self` for mkLib.");
+assert (assertMsg (user-inputs-has-src) "Missing attribute `src` for mkLib.");
+lib
diff --git a/lib/flake/default.nix b/lib/flake/default.nix
index 60f2dbe..77feed2 100644
--- a/lib/flake/default.nix
+++ b/lib/flake/default.nix
@@ -45,7 +45,7 @@ rec {
           "hosts"
           "channels-config"
           "templates"
-          "overlay-package-namespace"
+          "package-namespace"
           "alias"
         ];
 
@@ -65,11 +65,11 @@ rec {
           builtins.mapAttrs (name: input: input.lib) attrs-with-libs;
       in
       libs;
-
   };
 
   mkFlake = full-flake-options:
     let
+      package-namespace = full-flake-options.package-namespace or "internal";
       custom-flake-options = flake.without-snowfall-options full-flake-options;
       alias = full-flake-options.alias or { };
       systems = snowfall-lib.system.create-systems (full-flake-options.systems or { });
@@ -83,7 +83,7 @@ rec {
         alias = alias.modules or { };
       };
       overlays = snowfall-lib.overlay.create-overlays {
-        overlay-package-namespace = full-flake-options.overlay-package-namespace or null;
+        inherit package-namespace;
         extra-overlays = full-flake-options.extra-exported-overlays or { };
       };
 
@@ -95,7 +95,7 @@ rec {
               or (const { });
           user-outputs = user-outputs-builder channels;
           packages = snowfall-lib.package.create-packages {
-            inherit channels;
+            inherit channels package-namespace;
             overrides = (full-flake-options.packages or { }) // (user-outputs.packages or { });
             alias = alias.packages or { };
           };
@@ -125,7 +125,7 @@ rec {
         channelsConfig = full-flake-options.channels-config or { };
 
         channels.nixpkgs.overlaysBuilder = snowfall-lib.overlay.create-overlays-builder {
-          overlay-package-namespace = full-flake-options.overlay-package-namespace or null;
+          package-namespace = full-flake-options.package-namespace or null;
           extra-overlays = full-flake-options.overlays or [ ];
         };
 
diff --git a/lib/internal/default.nix b/lib/internal/default.nix
index 687fb62..dfa4a78 100644
--- a/lib/internal/default.nix
+++ b/lib/internal/default.nix
@@ -4,7 +4,7 @@
 }:
 
 let
-  inherit (core-inputs.nixpkgs.lib) assertMsg fix fold filterAttrs;
+  inherit (core-inputs.nixpkgs.lib) assertMsg fix fold filterAttrs callPackageWith;
 
   core-inputs-libs = snowfall-lib.flake.get-libs (snowfall-lib.flake.without-self core-inputs);
   user-inputs-libs = snowfall-lib.flake.get-libs (snowfall-lib.flake.without-self user-inputs);
@@ -27,10 +27,13 @@ let
       attrs = {
         inputs = snowfall-lib.flake.without-snowfall-inputs user-inputs;
         snowfall-inputs = core-inputs;
-        lib = snowfall-lib.attrs.merge-shallow [ base-lib user-lib ];
+        lib = snowfall-lib.attrs.merge-shallow [
+          base-lib
+          { internal = user-lib; }
+        ];
       };
       libs = builtins.map
-        (path: import path attrs)
+        (path: callPackageWith attrs path { })
         user-lib-modules;
     in
     snowfall-lib.attrs.merge-deep libs
@@ -38,7 +41,7 @@ let
 
   system-lib = snowfall-lib.attrs.merge-shallow [
     base-lib
-    user-lib
+    { internal = user-lib; }
   ];
 in
 {
diff --git a/lib/overlay/default.nix b/lib/overlay/default.nix
index 176e9d7..cc8dccd 100644
--- a/lib/overlay/default.nix
+++ b/lib/overlay/default.nix
@@ -13,11 +13,11 @@ in
   overlay = {
     # Create a flake-utils-plus overlays builder.
     # Type: Attrs -> Attrs -> [(a -> b -> c)]
-    # Usage: create-overlays { src = ./my-overlays; overlay-package-namespace = "my-packages"; }
+    # Usage: create-overlays { src = ./my-overlays; package-namespace = "my-packages"; }
     #   result: (channels: [ ... ])
     create-overlays-builder =
       { src ? user-overlays-root
-      , overlay-package-namespace ? null
+      , package-namespace ? "internal"
       , extra-overlays ? [ ]
       }: channels:
       let
@@ -29,18 +29,14 @@ in
               pkgs = final;
               channels = channels;
             };
-            user-packages-without-default = builtins.removeAttrs
-              (user-packages) [ "default" ];
           in
-          if overlay-package-namespace == null then
-            user-packages-without-default
-          else
-            {
-              ${overlay-package-namespace} =
-                (prev.${overlay-package-namespace} or { })
-                // user-packages-without-default;
-            };
-        overlays = [ user-packages-overlay ] ++ extra-overlays ++ (builtins.map create-overlay user-overlays);
+          {
+            ${package-namespace} =
+              (prev.${package-namespace} or { })
+              // user-packages;
+          };
+        overlays =
+          [ user-packages-overlay ] ++ extra-overlays ++ (builtins.map create-overlay user-overlays);
       in
       overlays;
 
@@ -48,12 +44,12 @@ in
     # Adapted from flake-utils-plus:
     # https://github.com/gytis-ivaskevicius/flake-utils-plus/blob/2bf0f91643c2e5ae38c1b26893ac2927ac9bd82a/lib/exportOverlays.nix
     # Type: Attrs -> Attrs
-    # Usage: create-overlays { src = ./my-overlays; packages-src = ./my-packages; overlay-package-namespace = "my-namespace"; extra-overlays = {}; }
+    # Usage: create-overlays { src = ./my-overlays; packages-src = ./my-packages; package-namespace = "my-namespace"; extra-overlays = {}; }
     #   result: { default = final: prev: ...; some-overlay = final: prev: ...; }
     create-overlays =
       { src ? user-overlays-root
       , packages-src ? user-packages-root
-      , overlay-package-namespace ? null
+      , package-namespace ? null
       , extra-overlays ? { }
       }:
       let
@@ -75,12 +71,12 @@ in
               channels = channel-systems.${prev.system};
             };
           in
-          if overlay-package-namespace == null then
+          if package-namespace == null then
             user-packages
           else
             {
-              ${overlay-package-namespace} =
-                (prev.${overlay-package-namespace} or { })
+              ${package-namespace} =
+                (prev.${package-namespace} or { })
                 // user-packages;
             };
 
@@ -93,13 +89,13 @@ in
                 user-overlay = import file (user-inputs // { inherit channels; });
                 packages = user-packages-overlay final prev;
                 prev-with-packages =
-                  if overlay-package-namespace == null then
+                  if package-namespace == null then
                     prev // packages
                   else
                     prev // {
-                      ${overlay-package-namespace} =
-                        (prev.${overlay-package-namespace} or { })
-                        // packages.${overlay-package-namespace};
+                      ${package-namespace} =
+                        (prev.${package-namespace} or { })
+                        // packages.${package-namespace};
                     };
                 user-overlay-packages =
                   user-overlay
@@ -140,12 +136,12 @@ in
                   channels = channel-systems.${prev.system};
                 };
               in
-              if overlay-package-namespace == null then
+              if package-namespace == null then
                 { ${name} = packages.${name}; }
               else
                 {
-                  ${overlay-package-namespace} =
-                    (prev.${overlay-package-namespace} or { })
+                  ${package-namespace} =
+                    (prev.${package-namespace} or { })
                     // { ${name} = packages.${name}; };
                 };
           in
diff --git a/lib/package/default.nix b/lib/package/default.nix
index a83fafe..3968ecd 100644
--- a/lib/package/default.nix
+++ b/lib/package/default.nix
@@ -4,13 +4,13 @@
 }:
 
 let
-  inherit (core-inputs.flake-utils-plus.lib) filterPackages;
-  inherit (core-inputs.nixpkgs.lib) assertMsg foldl mapAttrs;
+  inherit (core-inputs.flake-utils-plus.lib) filterPackages allSystems;
+  inherit (core-inputs.nixpkgs.lib) assertMsg foldl mapAttrs filterAttrs callPackageWith;
 
   user-packages-root = snowfall-lib.fs.get-snowfall-file "packages";
 in
 {
-  package = {
+  package = rec {
     # Create flake output packages.
     # Type: Attrs -> Attrs
     # Usage: create-packages { inherit channels; src = ./my-packages; overrides = { inherit another-package; }; alias.default = "another-package"; }
@@ -21,17 +21,26 @@ in
       , pkgs ? channels.nixpkgs
       , overrides ? { }
       , alias ? { }
+      , package-namespace ? "internal"
       }:
       let
         user-packages = snowfall-lib.fs.get-default-nix-files-recursive src;
-        create-package-metadata = package: {
-          name = builtins.unsafeDiscardStringContext (snowfall-lib.path.get-parent-directory package);
-          drv = pkgs.callPackage package {
-            inherit channels;
-            lib = snowfall-lib.internal.system-lib;
-            inputs = snowfall-lib.flake.without-src user-inputs;
+        create-package-metadata = package:
+          let
+            namespaced-packages = {
+              ${package-namespace} = packages-without-aliases;
+            };
+            extra-inputs = pkgs // namespaced-packages // {
+              inherit channels;
+              lib = snowfall-lib.internal.system-lib;
+              pkgs = pkgs // namespaced-packages;
+              inputs = snowfall-lib.flake.without-snowfall-inputs user-inputs;
+            };
+          in
+          {
+            name = builtins.unsafeDiscardStringContext (snowfall-lib.path.get-parent-directory package);
+            drv = callPackageWith extra-inputs package { };
           };
-        };
         packages-metadata = builtins.map create-package-metadata user-packages;
         merge-packages = packages: metadata:
           packages // {
diff --git a/lib/shell/default.nix b/lib/shell/default.nix
index 47161b6..aecd0e2 100644
--- a/lib/shell/default.nix
+++ b/lib/shell/default.nix
@@ -5,7 +5,7 @@
 
 let
   inherit (core-inputs.flake-utils-plus.lib) filterPackages;
-  inherit (core-inputs.nixpkgs.lib) assertMsg foldl mapAttrs;
+  inherit (core-inputs.nixpkgs.lib) assertMsg foldl mapAttrs callPackageWith;
 
   user-shells-root = snowfall-lib.fs.get-snowfall-file "shells";
 in
@@ -18,19 +18,23 @@ in
     create-shells =
       { channels
       , src ? user-shells-root
+      , pkgs ? channels.nixpkgs
       , overrides ? { }
       , alias ? { }
       }:
       let
         user-shells = snowfall-lib.fs.get-default-nix-files-recursive src;
         create-shell-metadata = shell:
-          {
-            name = builtins.unsafeDiscardStringContext (snowfall-lib.path.get-parent-directory shell);
-            drv = channels.nixpkgs.callPackage shell {
+          let
+            extra-inputs = pkgs // {
               inherit channels;
               lib = snowfall-lib.internal.system-lib;
               inputs = snowfall-lib.flake.without-src user-inputs;
             };
+          in
+          {
+            name = builtins.unsafeDiscardStringContext (snowfall-lib.path.get-parent-directory shell);
+            drv = callPackageWith extra-inputs shell { };
           };
         shells-metadata = builtins.map create-shell-metadata user-shells;
         merge-shells = shells: metadata:
@@ -41,8 +45,6 @@ in
         aliased-shells = mapAttrs (name: value: shells-without-aliases.${value}) alias;
         shells = shells-without-aliases // aliased-shells // overrides;
       in
-      filterPackages
-        channels.nixpkgs.system
-        shells;
+      filterPackages pkgs.system shells;
   };
 }