diff --git a/.github/FUNDING.yml b/.github/FUNDING.yml
new file mode 100644
index 0000000..fa76634
--- /dev/null
+++ b/.github/FUNDING.yml
@@ -0,0 +1,2 @@
+github:
+  - liskin
diff --git a/CHANGES.md b/CHANGES.md
index 8facb97..4af984a 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -41,6 +41,9 @@
     Instead, the manpage source is regenerated and manpage rebuilt
     automatically in CI.
 
+  * Added the `extensibleConf` field to `XConfig` which makes it easier for
+    contrib modules to have composable configuration (custom hooks, …).
+
 ## 0.15 (September 30, 2018)
 
   * Reimplement `sendMessage` to deal properly with windowset changes made
diff --git a/src/XMonad/Config.hs b/src/XMonad/Config.hs
index 5d176da..cd655d5 100644
--- a/src/XMonad/Config.hs
+++ b/src/XMonad/Config.hs
@@ -277,6 +277,7 @@ instance (a ~ Choose Tall (Choose (Mirror Tall) Full)) => Default (XConfig a) wh
     , XMonad.handleExtraArgs = \ xs theConf -> case xs of
                 [] -> return theConf
                 _ -> fail ("unrecognized flags:" ++ show xs)
+    , XMonad.extensibleConf     = M.empty
     }
 
 -- | The default set of configuration values itself
diff --git a/src/XMonad/Core.hs b/src/XMonad/Core.hs
index 435e84b..3e3c621 100644
--- a/src/XMonad/Core.hs
+++ b/src/XMonad/Core.hs
@@ -23,7 +23,7 @@ module XMonad.Core (
     XConf(..), XConfig(..), LayoutClass(..),
     Layout(..), readsLayout, Typeable, Message,
     SomeMessage(..), fromMessage, LayoutMessages(..),
-    StateExtension(..), ExtensionClass(..),
+    StateExtension(..), ExtensionClass(..), ConfExtension(..),
     runX, catchX, userCode, userCodeDef, io, catchIO, installSignalHandlers, uninstallSignalHandlers,
     withDisplay, withWindowSet, isRoot, runOnWorkspaces,
     getAtom, spawn, spawnPID, xfork, recompile, trace, whenJust, whenX,
@@ -122,6 +122,11 @@ data XConfig l = XConfig
     , rootMask           :: !EventMask           -- ^ The root events that xmonad is interested in
     , handleExtraArgs    :: !([String] -> XConfig Layout -> IO (XConfig Layout))
                                                  -- ^ Modify the configuration, complain about extra arguments etc. with arguments that are not handled by default
+    , extensibleConf     :: !(M.Map TypeRep ConfExtension)
+                                                 -- ^ Stores custom config information.
+                                                 --
+                                                 -- The module "XMonad.Util.ExtensibleConf" in xmonad-contrib
+                                                 -- provides additional information and a simple interface for using this.
     }
 
 
@@ -383,7 +388,7 @@ data LayoutMessages = Hide              -- ^ sent when a layout becomes non-visi
 instance Message LayoutMessages
 
 -- ---------------------------------------------------------------------
--- Extensible state
+-- Extensible state/config
 --
 
 -- | Every module must make the data it wants to store
@@ -410,6 +415,9 @@ data StateExtension =
   | forall a. (Read a, Show a, ExtensionClass a) => PersistentExtension a
     -- ^ Persistent extension
 
+-- | Existential type to store a config extension.
+data ConfExtension = forall a. Typeable a => ConfExtension a
+
 -- ---------------------------------------------------------------------
 -- | General utilities
 --