diff --git a/api_guide.md b/api_guide.md
index e7834e7..dc6f650 100644
--- a/api_guide.md
+++ b/api_guide.md
@@ -684,6 +684,25 @@ These can be paths, which is preferred as it results in better debug output:
 }
 ```
 
+### lib
+
+The `lib` option allows you to configure the flake's `lib` output.
+
+For example:
+
+```nix
+{
+  inputs.flakelight.url = "github:accelbread/flakelight";
+  outputs = { flakelight, ... }:
+    flakelight ./. {
+      lib = {
+        addFive = x: x + 5;
+        addFour = x: x + 4;
+      };
+    };
+}
+```
+
 ### functor
 
 The `functor` option allows you to make your flake callable.
@@ -759,6 +778,7 @@ The following options can be autoloaded with optional module args:
 - homeModules
 - homeConfigurations
 - flakelightModules
+- lib
 
 The following options can be autoloaded (no module args):
 
diff --git a/builtinModules/nixDir.nix b/builtinModules/nixDir.nix
index 9de71b9..3be433b 100644
--- a/builtinModules/nixDir.nix
+++ b/builtinModules/nixDir.nix
@@ -43,6 +43,7 @@ in
       homeConfigurations = autoImportArgs' [ "homeConfigurations" "home" ];
       flakelightModule = autoImport' "flakelightModule";
       flakelightModules = autoImportArgs' "flakelightModules";
+      lib = autoImportArgs' "lib";
       functor = autoImport' "functor";
     in
     mkMerge [
@@ -79,6 +80,7 @@ in
       (mkIf (homeConfigurations != null) { inherit homeConfigurations; })
       (mkIf (flakelightModule != null) { inherit flakelightModule; })
       (mkIf (flakelightModules != null) { inherit flakelightModules; })
+      (mkIf (lib != null) { inherit lib; })
       (mkIf (functor != null) { inherit functor; })
     ];
 }