diff --git a/src/event/CoarseTimerEvent.hxx b/src/event/CoarseTimerEvent.hxx
index 5a75d8b03..8edc10c45 100644
--- a/src/event/CoarseTimerEvent.hxx
+++ b/src/event/CoarseTimerEvent.hxx
@@ -54,7 +54,7 @@ class EventLoop;
 class CoarseTimerEvent final : AutoUnlinkIntrusiveListHook
 {
 	friend class TimerWheel;
-	friend class IntrusiveList<CoarseTimerEvent>;
+	friend struct IntrusiveListBaseHookTraits<CoarseTimerEvent>;
 
 	EventLoop &loop;
 
diff --git a/src/event/DeferEvent.hxx b/src/event/DeferEvent.hxx
index a96838656..2f274c33a 100644
--- a/src/event/DeferEvent.hxx
+++ b/src/event/DeferEvent.hxx
@@ -36,7 +36,7 @@ class EventLoop;
 class DeferEvent final : AutoUnlinkIntrusiveListHook
 {
 	friend class EventLoop;
-	friend class IntrusiveList<DeferEvent>;
+	friend struct IntrusiveListBaseHookTraits<DeferEvent>;
 
 	EventLoop &loop;
 
diff --git a/src/event/SocketEvent.hxx b/src/event/SocketEvent.hxx
index 955a37aa1..69fc7252f 100644
--- a/src/event/SocketEvent.hxx
+++ b/src/event/SocketEvent.hxx
@@ -46,7 +46,7 @@ class EventLoop;
 class SocketEvent final : IntrusiveListHook, public EventPollBackendEvents
 {
 	friend class EventLoop;
-	friend class IntrusiveList<SocketEvent>;
+	friend struct IntrusiveListBaseHookTraits<SocketEvent>;
 
 	EventLoop &loop;
 
diff --git a/src/util/IntrusiveList.hxx b/src/util/IntrusiveList.hxx
index 938850724..bde879dae 100644
--- a/src/util/IntrusiveList.hxx
+++ b/src/util/IntrusiveList.hxx
@@ -43,7 +43,8 @@ struct IntrusiveListNode {
 };
 
 class IntrusiveListHook {
-	template<typename T> friend class IntrusiveList;
+	template<typename T> friend struct IntrusiveListBaseHookTraits;
+	template<typename T, typename HookTraits> friend class IntrusiveList;
 
 protected:
 	IntrusiveListNode siblings;
@@ -117,13 +118,14 @@ struct IntrusiveListHookDetection {
 					IntrusiveListHook>;
 };
 
+/**
+ * For classes which embed #IntrusiveListHook as base class.
+ */
 template<typename T>
-class IntrusiveList {
+struct IntrusiveListBaseHookTraits {
 	template<typename U>
 	using Hook = typename IntrusiveListHookDetection<U>::type;
 
-	IntrusiveListNode head{&head, &head};
-
 	static constexpr T *Cast(IntrusiveListNode *node) noexcept {
 		auto *hook = &Hook<T>::Cast(*node);
 		return static_cast<T *>(hook);
@@ -141,6 +143,30 @@ class IntrusiveList {
 	static constexpr const auto &ToHook(const T &t) noexcept {
 		return static_cast<const Hook<T> &>(t);
 	}
+};
+
+template<typename T, typename HookTraits=IntrusiveListBaseHookTraits<T>>
+class IntrusiveList {
+	template<typename U>
+	using Hook = typename IntrusiveListHookDetection<U>::type;
+
+	IntrusiveListNode head{&head, &head};
+
+	static constexpr T *Cast(IntrusiveListNode *node) noexcept {
+		return HookTraits::Cast(node);
+	}
+
+	static constexpr const T *Cast(const IntrusiveListNode *node) noexcept {
+		return HookTraits::Cast(node);
+	}
+
+	static constexpr auto &ToHook(T &t) noexcept {
+		return HookTraits::ToHook(t);
+	}
+
+	static constexpr const auto &ToHook(const T &t) noexcept {
+		return HookTraits::ToHook(t);
+	}
 
 	static constexpr IntrusiveListNode &ToNode(T &t) noexcept {
 		return ToHook(t).siblings;