diff --git a/include/villas/nodes/zeromq.h b/include/villas/nodes/zeromq.h
index 3de66acd1..118346a0f 100644
--- a/include/villas/nodes/zeromq.h
+++ b/include/villas/nodes/zeromq.h
@@ -34,7 +34,7 @@
 
 #include "list.h"
 
-#if ZMQ_VERSION_MAJOR > 4 || (ZMQ_VERSION_MAJOR == 4 && ZMQ_VERSION_MINOR >= 2)
+#if ZMQ_BUILD_DRAFT_API && (ZMQ_VERSION_MAJOR > 4 || (ZMQ_VERSION_MAJOR == 4 && ZMQ_VERSION_MINOR >= 2))
   #define ZMQ_BUILD_DISH 1
 #endif
 
diff --git a/lib/api/actions/restart.c b/lib/api/actions/restart.c
index 14ee972da..2db2bf9b2 100644
--- a/lib/api/actions/restart.c
+++ b/lib/api/actions/restart.c
@@ -20,6 +20,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *********************************************************************************/
 
+#include <string.h>
+
 #include "plugin.h"
 #include "api.h"
 #include "super_node.h"
diff --git a/lib/hooks/convert.c b/lib/hooks/convert.c
index c54524544..f9753c094 100644
--- a/lib/hooks/convert.c
+++ b/lib/hooks/convert.c
@@ -24,6 +24,8 @@
  * @{
  */
 
+#include <string.h>
+
 #include "hook.h"
 #include "plugin.h"
 #include "sample.h"
diff --git a/lib/hooks/jitter_calc.c b/lib/hooks/jitter_calc.c
index 24375ec59..418ad854c 100644
--- a/lib/hooks/jitter_calc.c
+++ b/lib/hooks/jitter_calc.c
@@ -25,6 +25,7 @@
  */
 
 #include <inttypes.h>
+#include <string.h>
 
 #include "hook.h"
 #include "plugin.h"
diff --git a/lib/hooks/shift_ts.c b/lib/hooks/shift_ts.c
index 021e14636..589c4ec58 100644
--- a/lib/hooks/shift_ts.c
+++ b/lib/hooks/shift_ts.c
@@ -24,6 +24,8 @@
  * @{
  */
 
+#include <string.h>
+
 #include "hook.h"
 #include "plugin.h"
 #include "timing.h"
diff --git a/lib/hooks/stats.c b/lib/hooks/stats.c
index 449b062de..1998d51be 100644
--- a/lib/hooks/stats.c
+++ b/lib/hooks/stats.c
@@ -24,6 +24,8 @@
  * @{
  */
 
+#include <string.h>
+
 #include "common.h"
 #include "advio.h"
 #include "hook.h"
diff --git a/lib/io/csv.c b/lib/io/csv.c
index d573ff9c8..da819ee3c 100644
--- a/lib/io/csv.c
+++ b/lib/io/csv.c
@@ -22,6 +22,7 @@
 
 #include <ctype.h>
 #include <inttypes.h>
+#include <string.h>
 
 #include "io/csv.h"
 #include "plugin.h"
diff --git a/lib/nodes/influxdb.c b/lib/nodes/influxdb.c
index c261bbc11..47b4ca6df 100644
--- a/lib/nodes/influxdb.c
+++ b/lib/nodes/influxdb.c
@@ -20,6 +20,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *********************************************************************************/
 
+#include <string.h>
+
 #include "node.h"
 #include "plugin.h"
 #include "config.h"
diff --git a/lib/nodes/signal.c b/lib/nodes/signal.c
index f34efd2fa..265bd3b20 100644
--- a/lib/nodes/signal.c
+++ b/lib/nodes/signal.c
@@ -22,6 +22,7 @@
  *********************************************************************************/
 
 #include <math.h>
+#include <string.h>
 
 #include "node.h"
 #include "plugin.h"
diff --git a/lib/nodes/stats.c b/lib/nodes/stats.c
index f883d1fe4..40d130f75 100644
--- a/lib/nodes/stats.c
+++ b/lib/nodes/stats.c
@@ -24,6 +24,8 @@
  * @{
  */
 
+#include <string.h>
+
 #include "nodes/stats.h"
 #include "hook.h"
 #include "plugin.h"
diff --git a/lib/nodes/test_rtt.c b/lib/nodes/test_rtt.c
index 7039bb3cc..84e1e77d9 100644
--- a/lib/nodes/test_rtt.c
+++ b/lib/nodes/test_rtt.c
@@ -21,6 +21,7 @@
  *********************************************************************************/
 
 #include <stdio.h>
+#include <string.h>
 #include <sys/stat.h>
 
 #include "node.h"
diff --git a/lib/nodes/zeromq.c b/lib/nodes/zeromq.c
index f6319a37e..6852c7b86 100644
--- a/lib/nodes/zeromq.c
+++ b/lib/nodes/zeromq.c
@@ -20,6 +20,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *********************************************************************************/
 
+#include <string.h>
 #include <zmq.h>
 
 #if ZMQ_VERSION_MAJOR < 4 || (ZMQ_VERSION_MAJOR == 4 && ZMQ_VERSION_MINOR <= 1)
diff --git a/lib/plugin.c b/lib/plugin.c
index e26b19d83..480a06bc4 100644
--- a/lib/plugin.c
+++ b/lib/plugin.c
@@ -21,6 +21,7 @@
  *********************************************************************************/
 
 #include <dlfcn.h>
+#include <string.h>
 
 #include "plugin.h"