diff --git a/src/libei-device.c b/src/libei-device.c
index aeb40a9..cc9982d 100644
--- a/src/libei-device.c
+++ b/src/libei-device.c
@@ -157,6 +157,10 @@ _public_
 OBJECT_IMPLEMENT_GETTER(ei_keymap, size, size_t);
 _public_
 OBJECT_IMPLEMENT_GETTER(ei_keymap, device, struct ei_device *);
+_public_
+OBJECT_IMPLEMENT_GETTER(ei_keymap, user_data, void *);
+_public_
+OBJECT_IMPLEMENT_SETTER(ei_keymap, user_data, void *);
 
 static void
 ei_keymap_destroy(struct ei_keymap *keymap)
diff --git a/src/libei-private.h b/src/libei-private.h
index 96d3254..777156d 100644
--- a/src/libei-private.h
+++ b/src/libei-private.h
@@ -132,6 +132,7 @@ struct ei_device {
 struct ei_keymap {
 	struct object object;
 	struct ei_device *device;
+	void *user_data;
 	enum ei_keymap_type type;
 	int fd;
 	size_t size;
diff --git a/src/libei.h b/src/libei.h
index 24e0db4..4579226 100644
--- a/src/libei.h
+++ b/src/libei.h
@@ -654,6 +654,12 @@ ei_keymap_ref(struct ei_keymap *keymap);
 struct ei_keymap *
 ei_keymap_unref(struct ei_keymap *keymap);
 
+void
+ei_keymap_set_user_data(struct ei_keymap *keymap, void *user_data);
+
+void *
+ei_keymap_get_user_data(struct ei_keymap *keymap);
+
 /**
  * Notify the server that the client is no longer listening to events
  * from this device.
diff --git a/src/libeis-device.c b/src/libeis-device.c
index 207b697..d3aa138 100644
--- a/src/libeis-device.c
+++ b/src/libeis-device.c
@@ -43,6 +43,10 @@ _public_
 OBJECT_IMPLEMENT_GETTER(eis_keymap, size, size_t);
 _public_
 OBJECT_IMPLEMENT_GETTER(eis_keymap, device, struct eis_device *);
+_public_
+OBJECT_IMPLEMENT_GETTER(eis_keymap, user_data, void *);
+_public_
+OBJECT_IMPLEMENT_SETTER(eis_keymap, user_data, void *);
 
 static void
 eis_keymap_destroy(struct eis_keymap *keymap)
diff --git a/src/libeis-private.h b/src/libeis-private.h
index 6bb77db..515bd82 100644
--- a/src/libeis-private.h
+++ b/src/libeis-private.h
@@ -174,6 +174,7 @@ struct eis_event {
 struct eis_keymap {
 	struct object object;
 	struct eis_device *device;
+	void *user_data;
 	enum eis_keymap_type type;
 	int fd;
 	size_t size;
diff --git a/src/libeis.h b/src/libeis.h
index 7213f80..2618474 100644
--- a/src/libeis.h
+++ b/src/libeis.h
@@ -601,6 +601,12 @@ eis_keymap_ref(struct eis_keymap *keymap);
 struct eis_keymap *
 eis_keymap_unref(struct eis_keymap *keymap);
 
+void *
+eis_keymap_get_user_data(struct eis_keymap *eis_keymap);
+
+void
+eis_keymap_set_user_data(struct eis_keymap *eis_keymap, void *user_data);
+
 /**
  * Return the device this keymap belongs to, or `NULL` if it has not yet
  * been assigned to a device.