diff --git a/include/villas/nodes/ngsi.hpp b/include/villas/nodes/ngsi.hpp
index 922e89d7b..a8557dd52 100644
--- a/include/villas/nodes/ngsi.hpp
+++ b/include/villas/nodes/ngsi.hpp
@@ -62,9 +62,8 @@ struct ngsi {
 
 	struct curl_slist *headers;	/**< List of HTTP request headers for libcurl */
 
-	CURL *curl;			/**< libcurl: handle */
-
 	struct {
+		CURL *curl;		/**< libcurl: handle */
 		struct vlist signals;	/**< A mapping between indices of the VILLASnode samples and the attributes in ngsi::context */
 	} in, out;
 };
diff --git a/lib/nodes/ngsi.cpp b/lib/nodes/ngsi.cpp
index 2275ccc4b..e9144b224 100644
--- a/lib/nodes/ngsi.cpp
+++ b/lib/nodes/ngsi.cpp
@@ -13,20 +13,23 @@
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * along with this program.	If not, see <http://www.gnu.org/licenses/>.
  **********************************************************************************/
 
 #include <cstring>
 #include <cstdio>
 
-#include <curl/curl.h>
+#include <unistd.h>
 #include <jansson.h>
 #include <pthread.h>
-#include <unistd.h>
+#include <stdio.h>
+#include <openssl/err.h>
+#include <openssl/opensslv.h>
+#include <curl/curl.h>
 
 #include <villas/nodes/ngsi.hpp>
 #include <villas/utils.hpp>
@@ -39,14 +42,43 @@ using namespace villas;
 using namespace villas::utils;
 
 /* Some global settings */
-static char *name = nullptr;
+
+#if OPENSSL_VERSION_NUMBER < 0x010003000L
+  // See: https://curl.haxx.se/libcurl/c/opensslthreadlock.html
+  #define CURL_SSL_REQUIRES_LOCKING
+#endif
+
+#ifdef CURL_SSL_REQUIRES_LOCKING
+/** This array will store all of the mutexes available to OpenSSL. */
+static pthread_mutex_t *mutex_buf = NULL;
+
+void handle_error(const char *file, int lineno, const char *msg)
+{
+	error("** %s:%d %s\n", file, lineno, msg);
+	ERR_print_errors_fp(stderr);
+	/* exit(-1); */
+}
+
+static void curl_ssl_locking_function(int mode, int n, const char *file, int line)
+{
+	if (mode & CRYPTO_LOCK)
+		pthread_mutex_lock(&mutex_buf[n]);
+	else
+		pthread_mutex_unlock(&mutex_buf[n]);
+}
+
+static unsigned long curl_ssl_thread_id_function(void)
+{
+	return ((unsigned long) pthread_self());
+}
+#endif /* CURL_SSL_REQUIRES_LOCKING */
 
 enum NgsiFlags {
-	NGSI_ENTITY_ATTRIBUTES_IN  = (1 << 0),
+	NGSI_ENTITY_ATTRIBUTES_IN	= (1 << 0),
 	NGSI_ENTITY_ATTRIBUTES_OUT = (1 << 1),
-	NGSI_ENTITY_ATTRIBUTES     = NGSI_ENTITY_ATTRIBUTES_IN | NGSI_ENTITY_ATTRIBUTES_OUT,
-	NGSI_ENTITY_VALUES         = (1 << 2),
-	NGSI_ENTITY_METADATA       = (1 << 3),
+	NGSI_ENTITY_ATTRIBUTES		 = NGSI_ENTITY_ATTRIBUTES_IN | NGSI_ENTITY_ATTRIBUTES_OUT,
+	NGSI_ENTITY_VALUES				 = (1 << 2),
+	NGSI_ENTITY_METADATA			 = (1 << 3),
 };
 
 class NgsiMetadata {
@@ -185,8 +217,8 @@ public:
 
 			for (auto &meta : metadata) {
 				json_array_append_new(json_metadatas, json_pack("{ s: s, s: s, s: s }",
-					"name",  meta.name.c_str(),
-					"type",  meta.type.c_str(),
+					"name",	meta.name.c_str(),
+					"type",	meta.type.c_str(),
 					"value", meta.value.c_str()
 				));
 			}
@@ -367,7 +399,7 @@ static int ngsi_parse_entity(struct node *n, json_t *json_entity, struct sample
 
 #ifdef NGSI_VECTORS
 		smp->flags |= (int) (SampleFlags::HAS_SEQUENCE |
-		                     SampleFlags::HAS_TS_ORIGIN);
+												 SampleFlags::HAS_TS_ORIGIN);
 #endif
 	}
 
@@ -490,8 +522,10 @@ static int ngsi_request_context_query(CURL *handle, const char *endpoint, json_t
 	json_t *json_request = json_pack("{ s: [ o ] }", "entities", json_entity);
 
 	ret = ngsi_request(handle, endpoint, "queryContext", json_request, &json_response);
-	if (ret)
+	if (ret) {
+		ret = -1;
 		goto out;
+	}
 
 	ret = ngsi_parse_context_response(json_response, &code, &reason, json_rentity);
 	if (ret)
@@ -532,12 +566,37 @@ out:	json_decref(json_request);
 
 int ngsi_type_start(villas::node::SuperNode *sn)
 {
+#ifdef CURL_SSL_REQUIRES_LOCKING
+	mutex_buf = new pthread_mutex_t[CRYPTO_num_locks()];
+	if (!mutex_buf)
+		return -1;
+
+	for (int i = 0; i < CRYPTO_num_locks(); i++)
+		pthread_mutex_init(&mutex_buf[i], nullptr);
+
+	CRYPTO_set_id_callback(curl_ssl_thread_id_function);
+	CRYPTO_set_locking_callback(curl_ssl_locking_function);
+
+	info("Setup libcurl/openssl locking primitives");
+#endif /* CURL_SSL_REQUIRES_LOCKING */
+
 	return curl_global_init(CURL_GLOBAL_ALL);
 }
 
 int ngsi_type_stop()
 {
-	free(name);
+#ifdef CURL_SSL_REQUIRES_LOCKING
+	if (!mutex_buf)
+		return -1;
+
+	CRYPTO_set_id_callback(NULL);
+	CRYPTO_set_locking_callback(NULL);
+
+	for (int i = 0; i < CRYPTO_num_locks(); i++)
+		pthread_mutex_destroy(&mutex_buf[i]);
+
+	delete mutex_buf;
+#endif /* CURL_SSL_REQUIRES_LOCKING */
 
 	curl_global_cleanup();
 
@@ -605,7 +664,8 @@ int ngsi_start(struct node *n)
 	struct ngsi *i = (struct ngsi *) n->_vd;
 	int ret;
 
-	i->curl = curl_easy_init();
+	i->in.curl = curl_easy_init();
+	i->out.curl = curl_easy_init();
 	i->headers = nullptr;
 
 	if (i->access_token) {
@@ -623,16 +683,20 @@ int ngsi_start(struct node *n)
 	i->headers = curl_slist_append(i->headers, "Accept: application/json");
 	i->headers = curl_slist_append(i->headers, "Content-Type: application/json");
 
-	curl_easy_setopt(i->curl, CURLOPT_SSL_VERIFYPEER, i->ssl_verify);
-	curl_easy_setopt(i->curl, CURLOPT_TIMEOUT_MS, i->timeout * 1e3);
-	curl_easy_setopt(i->curl, CURLOPT_HTTPHEADER, i->headers);
-	curl_easy_setopt(i->curl, CURLOPT_USERAGENT, USER_AGENT);
+	CURL *handles[] = { i->in.curl, i->out.curl };
+
+	for (unsigned p = 0; p < ARRAY_LEN(handles); p++) {
+		curl_easy_setopt(handles[p], CURLOPT_SSL_VERIFYPEER, i->ssl_verify);
+		curl_easy_setopt(handles[p], CURLOPT_TIMEOUT_MS, i->timeout * 1e3);
+		curl_easy_setopt(handles[p], CURLOPT_HTTPHEADER, i->headers);
+		curl_easy_setopt(handles[p], CURLOPT_USERAGENT, USER_AGENT);
+	}
 
 	/* Create entity and atributes */
 	if (i->create) {
 		json_t *json_entity = ngsi_build_entity(n, nullptr, 0, NGSI_ENTITY_ATTRIBUTES | NGSI_ENTITY_METADATA);
 
-		ret = ngsi_request_context_update(i->curl, i->endpoint, "APPEND", json_entity);
+		ret = ngsi_request_context_update(i->out.curl, i->endpoint, "APPEND", json_entity);
 		if (ret)
 			throw RuntimeError("Failed to create NGSI context for node {}", node_name(n));
 
@@ -652,11 +716,12 @@ int ngsi_stop(struct node *n)
 	/* Delete complete entity (not just attributes) */
 	json_t *json_entity = ngsi_build_entity(n, nullptr, 0, 0);
 
-	ret = ngsi_request_context_update(i->curl, i->endpoint, "DELETE", json_entity);
+	ret = ngsi_request_context_update(i->out.curl, i->endpoint, "DELETE", json_entity);
 
 	json_decref(json_entity);
 
-	curl_easy_cleanup(i->curl);
+	curl_easy_cleanup(i->in.curl);
+	curl_easy_cleanup(i->out.curl);
 	curl_slist_free_all(i->headers);
 
 	return ret;
@@ -673,7 +738,7 @@ int ngsi_read(struct node *n, struct sample *smps[], unsigned cnt, unsigned *rel
 	json_t *json_rentity;
 	json_t *json_entity = ngsi_build_entity(n, nullptr, 0, 0);
 
-	ret = ngsi_request_context_query(i->curl, i->endpoint, json_entity, &json_rentity);
+	ret = ngsi_request_context_query(i->in.curl, i->endpoint, json_entity, &json_rentity);
 	if (ret)
 		goto out;
 
@@ -694,7 +759,7 @@ int ngsi_write(struct node *n, struct sample *smps[], unsigned cnt, unsigned *re
 
 	json_t *json_entity = ngsi_build_entity(n, smps, cnt, NGSI_ENTITY_ATTRIBUTES_OUT | NGSI_ENTITY_VALUES);
 
-	ret = ngsi_request_context_update(i->curl, i->endpoint, "UPDATE", json_entity);
+	ret = ngsi_request_context_update(i->out.curl, i->endpoint, "UPDATE", json_entity);
 
 	json_decref(json_entity);