diff --git a/CMakeLists-implied-options.txt b/CMakeLists-implied-options.txt
index d5cfdd9f2..c75407f62 100644
--- a/CMakeLists-implied-options.txt
+++ b/CMakeLists-implied-options.txt
@@ -47,7 +47,7 @@ if (LWS_PLAT_OPTEE)
 	set(LWS_WITH_UDP 0)
 endif()
 
-if (LWS_PLAT_FREERTOS)
+if (LWS_PLAT_FREERTOS OR (${CMAKE_SYSTEM_NAME} MATCHES "QNX"))
 	message(STATUS "No LWS_WITH_DIR or LWS_WITH_LEJP_CONF")
 	set(LWS_WITH_DIR OFF)
 	set(LWS_WITH_LEJP_CONF OFF)
diff --git a/cmake/LwsCheckRequirements.cmake b/cmake/LwsCheckRequirements.cmake
index fa3fb9fdd..9fc76e69c 100644
--- a/cmake/LwsCheckRequirements.cmake
+++ b/cmake/LwsCheckRequirements.cmake
@@ -75,7 +75,9 @@ MACRO(require_pthreads result)
 		if (WIN32)
 			set(PTHREAD_LIB ${LWS_EXT_PTHREAD_LIBRARIES})
 		else()
-			set(PTHREAD_LIB pthread)
+			if (NOT ${CMAKE_SYSTEM_NAME} MATCHES "QNX")
+				set(PTHREAD_LIB pthread)
+			endif()
 		endif()
 	endif()
 ENDMACRO()
diff --git a/contrib/cross-aarch64-qnx.cmake b/contrib/cross-aarch64-qnx.cmake
new file mode 100644
index 000000000..404d1d989
--- /dev/null
+++ b/contrib/cross-aarch64-qnx.cmake
@@ -0,0 +1,50 @@
+#
+# CMake Toolchain file for crosscompiling aarch64 for QNX.
+#
+# This can be used when running cmake in the following way:
+#  cd build/
+#  cmake .. -DCMAKE_TOOLCHAIN_FILE=../cross-aarch64-qnx.cmake
+#
+
+# adapt to your toolchain path
+set(CROSS_PATH /var/toolchain/qnx5.4/host/linux/x86_64/usr)
+
+# Target operating system name.
+set(CMAKE_SYSTEM_NAME QNX)
+set(BUILD_SHARED_LIBS OFF)
+set(CMAKE_SYSTEM_PROCESSOR aarch64)
+
+# Name of C compiler.
+set(CMAKE_C_COMPILER "${CROSS_PATH}/bin/ntoaarch64-gcc")
+set(CMAKE_CXX_COMPILER "${CROSS_PATH}/bin/ntoaarch64-g++")
+
+set(CMAKE_C_FLAGS "-Wno-error")
+set(CMAKE_FIND_ROOT_PATH "${CROSS_PATH}")
+
+#
+# Different build system distros set release optimization level to different
+# things according to their local policy, eg, Fedora is -O2 and Ubuntu is -O3
+# here.  Actually the build system's local policy is completely unrelated to
+# our desire for cross-build release optimization policy for code built to run
+# on a completely different target than the build system itself.
+#
+# Since this goes last on the compiler commandline we have to override it to a
+# sane value for cross-build here.  Notice some gcc versions enable broken
+# optimizations with -O3.
+#
+if (CMAKE_BUILD_TYPE MATCHES RELEASE OR CMAKE_BUILD_TYPE MATCHES Release OR CMAKE_BUILD_TYPE MATCHES release)
+	set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} -O2")
+	set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O2")
+endif()
+
+# Where to look for the target environment. (More paths can be added here)
+set(CMAKE_FIND_ROOT_PATH "${CROSS_PATH}")
+
+# Adjust the default behavior of the FIND_XXX() commands:
+# search programs in the host environment only.
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+
+# Search headers and libraries in the target environment only.
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+
diff --git a/lib/misc/getifaddrs.c b/lib/misc/getifaddrs.c
index 98e768c78..125088e22 100644
--- a/lib/misc/getifaddrs.c
+++ b/lib/misc/getifaddrs.c
@@ -90,7 +90,11 @@ getifaddrs2(struct ifaddrs **ifap, int af, int siocgifconf, int siocgifflags,
 			ret = ENOMEM;
 			goto error_out;
 		}
+#if defined(__QNX__)
+		ifconf.ifc_len = (short)(int)buf_size;
+#else
 		ifconf.ifc_len = (int)buf_size;
+#endif
 		ifconf.ifc_buf = buf;
 
 		/*
diff --git a/lib/plat/unix/unix-sockets.c b/lib/plat/unix/unix-sockets.c
index 24fdb7040..07df994cc 100644
--- a/lib/plat/unix/unix-sockets.c
+++ b/lib/plat/unix/unix-sockets.c
@@ -236,7 +236,8 @@ lws_plat_set_socket_options_ip(lws_sockfd_type fd, uint8_t pri, int lws_flags)
       !defined(__OpenBSD__) && \
       !defined(__sun) && \
       !defined(__HAIKU__) && \
-      !defined(__CYGWIN__)
+      !defined(__CYGWIN__) && \
+      !defined(__QNX__)
 
 	/* the BSDs don't have SO_PRIORITY */
 
diff --git a/minimal-examples-lowlevel/http-client/minimal-http-client-captive-portal/CMakeLists.txt b/minimal-examples-lowlevel/http-client/minimal-http-client-captive-portal/CMakeLists.txt
index e7be79a96..f332dc5b9 100644
--- a/minimal-examples-lowlevel/http-client/minimal-http-client-captive-portal/CMakeLists.txt
+++ b/minimal-examples-lowlevel/http-client/minimal-http-client-captive-portal/CMakeLists.txt
@@ -10,6 +10,7 @@ set(SAMP lws-minimal-http-client-captive-portal)
 set(SRCS minimal-http-client-captive-portal.c)
 
 set(requirements 1)
+require_pthreads(requirements)
 require_lws_config(LWS_ROLE_H1 1 requirements)
 require_lws_config(LWS_WITH_TLS 1 requirements)
 require_lws_config(LWS_WITH_CLIENT 1 requirements)
@@ -19,9 +20,9 @@ if (NOT WIN32 AND requirements)
 	add_executable(${SAMP} ${SRCS})
 
 	if (websockets_shared)
-		target_link_libraries(${SAMP} websockets_shared pthread ${LIBWEBSOCKETS_DEP_LIBS})
+		target_link_libraries(${SAMP} websockets_shared ${PTHREAD_LIB} ${LIBWEBSOCKETS_DEP_LIBS})
 		add_dependencies(${SAMP} websockets_shared)
 	else()
-		target_link_libraries(${SAMP} websockets pthread ${LIBWEBSOCKETS_DEP_LIBS})
+		target_link_libraries(${SAMP} websockets ${PTHREAD_LIB} ${LIBWEBSOCKETS_DEP_LIBS})
 	endif()
 endif()
diff --git a/minimal-examples-lowlevel/raw/minimal-raw-serial/minimal-raw-file.c b/minimal-examples-lowlevel/raw/minimal-raw-serial/minimal-raw-file.c
index 45d50af0a..57ba8f096 100644
--- a/minimal-examples-lowlevel/raw/minimal-raw-serial/minimal-raw-file.c
+++ b/minimal-examples-lowlevel/raw/minimal-raw-serial/minimal-raw-file.c
@@ -109,7 +109,11 @@ callback_raw_test(struct lws *wsi, enum lws_callback_reasons reason,
 #if defined(__linux__)
 				CBAUD |
 #endif
-				CSIZE | CSTOPB | PARENB | CRTSCTS);
+				CSIZE | CSTOPB | PARENB
+#if !defined(__QNX__)
+				| CRTSCTS
+#endif
+		);
 		tio.c_cflag |= 0x1412 | CS8 | CREAD | CLOCAL;
 
 		tcsetattr(vhd->filefd, TCSANOW, &tio);