diff --git a/CMakeLists.txt b/CMakeLists.txt
index f1cd3b13e..bf0b8ac94 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -52,6 +52,7 @@ include(CheckIncludeFile)
 include(FeatureSummary)
 include(GNUInstallDirs)
 include(GetVersion)
+include(FindSymbol)
 include(CMakeDependentOption)
 
 # Compiler flags
@@ -90,7 +91,7 @@ find_package(Etherlab)
 # Check for tools
 find_program(PASTE NAMES paste)
 if(NOT PASTE)
-	message(SEND_ERROR "GNU paste is missing. Please install coreutils")
+    message(SEND_ERROR "GNU paste is missing. Please install coreutils")
 endif()
 
 # Check programs
@@ -124,6 +125,9 @@ if(NOT RE_FOUND)
     pkg_check_modules(RE IMPORTED_TARGET libre>=0.5.6)
 endif()
 
+# Check if libwebsockets is build with deflate extension
+FindSymbol(${LIBWEBSOCKETS_LINK_LIBRARIES} lws_extension_callback_pm_deflate LWS_DEFLATE_FOUND)
+
 # Build options
 cmake_dependent_option(WITH_HOOKS           "Build with support for processing hook plugins"        ON "" OFF)
 cmake_dependent_option(WITH_WEB             "Build with internal webserver"                         ON "LIBWEBSOCKETS_FOUND" OFF)
diff --git a/cmake/FindSymbol.cmake b/cmake/FindSymbol.cmake
new file mode 100644
index 000000000..da933e021
--- /dev/null
+++ b/cmake/FindSymbol.cmake
@@ -0,0 +1,36 @@
+# CMakeLists.txt.
+#
+# @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
+# @copyright 2014-2020, Institute for Automation of Complex Power Systems, EONERC
+# @license GNU General Public License (version 3)
+#
+# VILLASnode
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+###################################################################################
+
+function(FindSymbol LIBRARY SYMBOL FOUND)
+	find_program(OBJDUMP_EXECUTABLE NAMES objdump)
+
+	execute_process(
+		COMMAND /bin/sh -c "${OBJDUMP_EXECUTABLE} -T ${LIBRARY} | grep ${SYMBOL} | wc -l"
+		OUTPUT_VARIABLE OUTPUT
+	)
+
+	if(OUTPUT GREATER 0)
+		set(${FOUND} "${SYMBOL}" PARENT_SCOPE)
+	else()
+		set(${FOUND} "${SYMBOL}-NOTFOUND" PARENT_SCOPE)
+	endif()
+endfunction()
diff --git a/include/villas/node/config.h.in b/include/villas/node/config.h.in
index b2e7b443a..54df6a1f7 100644
--- a/include/villas/node/config.h.in
+++ b/include/villas/node/config.h.in
@@ -65,3 +65,6 @@
 #cmakedefine PROTOBUF_FOUND
 #cmakedefine LIBNL3_ROUTE_FOUND
 #cmakedefine IBVERBS_FOUND
+
+/* Library features */
+#cmakedefine LWS_DEFLATE_FOUND
diff --git a/lib/web.cpp b/lib/web.cpp
index 96397611b..28aa79704 100644
--- a/lib/web.cpp
+++ b/lib/web.cpp
@@ -110,6 +110,7 @@ static lws_http_mount mounts[] = {
 
 /** List of libwebsockets extensions. */
 static const lws_extension extensions[] = {
+#ifdef LWS_DEFLATE_FOUND
 	{
 		.name = "permessage-deflate",
 		.callback = lws_extension_callback_pm_deflate,
@@ -120,6 +121,7 @@ static const lws_extension extensions[] = {
 		.callback = lws_extension_callback_pm_deflate,
 		.client_offer = "deflate_frame"
 	},
+#endif /* LWS_DEFLATE_FOUND */
 	{ nullptr /* terminator */ }
 };
 
diff --git a/src/villas-relay.cpp b/src/villas-relay.cpp
index 5e9714671..86f2f6645 100644
--- a/src/villas-relay.cpp
+++ b/src/villas-relay.cpp
@@ -522,6 +522,7 @@ int Relay::main() {
 }
 
 const std::vector<lws_extension> Relay::extensions = {
+#ifdef LWS_DEFLATE_FOUND
 	{
 		"permessage-deflate",
 		lws_extension_callback_pm_deflate,
@@ -532,6 +533,7 @@ const std::vector<lws_extension> Relay::extensions = {
 		lws_extension_callback_pm_deflate,
 		"deflate_frame"
 	},
+#endif /* LWS_DEFLATE_FOUND */
 	{ nullptr /* terminator */ }
 };