diff --git a/src/interfaces/handler.h b/src/interfaces/handler.h
index b3aebf7e14d..5de131ee98e 100644
--- a/src/interfaces/handler.h
+++ b/src/interfaces/handler.h
@@ -5,15 +5,11 @@
 #ifndef BITCOIN_INTERFACES_HANDLER_H
 #define BITCOIN_INTERFACES_HANDLER_H
 
+#include <btcsignals.h>
+
 #include <functional>
 #include <memory>
 
-namespace boost {
-namespace signals2 {
-class connection;
-} // namespace signals2
-} // namespace boost
-
 namespace interfaces {
 
 //! Generic interface for managing an event handler or callback function
diff --git a/src/node/interface_ui.h b/src/node/interface_ui.h
index ce5171bb518..8c90bdf4fef 100644
--- a/src/node/interface_ui.h
+++ b/src/node/interface_ui.h
@@ -6,6 +6,8 @@
 #ifndef BITCOIN_NODE_INTERFACE_UI_H
 #define BITCOIN_NODE_INTERFACE_UI_H
 
+#include <btcsignals.h>
+
 #include <cstdint>
 #include <functional>
 #include <string>
@@ -15,12 +17,6 @@ class CBlockIndex;
 enum class SynchronizationState;
 struct bilingual_str;
 
-namespace boost {
-namespace signals2 {
-class connection;
-}
-} // namespace boost
-
 /** Signals for UI communication. */
 class CClientUIInterface
 {