diff --git a/src/hci.h b/src/hci.h
index 60d65fb77..0d24c3e5a 100644
--- a/src/hci.h
+++ b/src/hci.h
@@ -48,6 +48,10 @@
 #include <stdlib.h>
 #include <stdarg.h>
 
+#if defined __cplusplus
+extern "C" {
+#endif
+    
 // packet header lenghts
 #define HCI_CMD_DATA_PKT_HDR	  0x03
 #define HCI_ACL_DATA_PKT_HDR	  0x04
@@ -261,3 +265,7 @@ void hci_emit_hci_open_failed();
 void hci_emit_btstack_version();
 void hci_emit_system_bluetooth_enabled(uint8_t enabled);
 void hci_emit_remote_name_cached(bd_addr_t *addr, device_name_t *name);
+
+#if defined __cplusplus
+}
+#endif
diff --git a/src/hci_transport.h b/src/hci_transport.h
index 9c49c8e15..539b2aa3c 100644
--- a/src/hci_transport.h
+++ b/src/hci_transport.h
@@ -42,6 +42,10 @@
 #include <stdint.h>
 #include <btstack/run_loop.h>
 
+#if defined __cplusplus
+extern "C" {
+#endif
+    
 /* HCI packet types */
 typedef struct {
     int    (*open)(void *transport_config);
@@ -69,4 +73,7 @@ extern hci_transport_t * hci_transport_h4_instance();
 extern hci_transport_t * hci_transport_h5_instance();
 extern hci_transport_t * hci_transport_usb_instance();
 
+#if defined __cplusplus
+}
+#endif
 
diff --git a/src/l2cap.h b/src/l2cap.h
index 4297024c2..dc409ad41 100644
--- a/src/l2cap.h
+++ b/src/l2cap.h
@@ -44,6 +44,10 @@
 #include <btstack/utils.h>
 #include <btstack/btstack.h>
 
+#if defined __cplusplus
+extern "C" {
+#endif
+    
 #define L2CAP_SIG_ID_INVALID 0
 
 typedef enum {
@@ -130,3 +134,7 @@ void l2cap_decline_connection_internal(uint16_t local_cid, uint8_t reason);
 void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status);
 void l2cap_emit_channel_closed(l2cap_channel_t *channel);
 void l2cap_emit_connection_request(l2cap_channel_t *channel);
+
+#if defined __cplusplus
+}
+#endif