diff --git a/build.sh b/build.sh
index 8c00356a..dce099f6 100755
--- a/build.sh
+++ b/build.sh
@@ -75,4 +75,8 @@ fi
 
 [ "${PORTS_FS_MARK}" = "y" ] && ./phoenix-rtos-ports/fs_mark/build.sh
 
+[ "${PORTS_CHECK}" = "y" ] && ./phoenix-rtos-ports/check/build.sh
+
+[ "${PORTS_LWIP_TESTS}" = "y" ] && ./phoenix-rtos-ports/lwip-tests/build.sh
+
 exit 0
diff --git a/check/build.sh b/check/build.sh
new file mode 100755
index 00000000..9e482041
--- /dev/null
+++ b/check/build.sh
@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+
+set -e
+
+CHECK_VER="0.10.0"
+CHECK="check-$CHECK_VER"
+CHECK_PKG_URL="https://github.com/libcheck/check/archive/refs/tags/${CHECK_VER}.tar.gz"
+CHECK_PKG_MIRROR_URL="https://files.phoesys.com/ports/${CHECK}.tar.gz"
+
+PREFIX_CHECK="${PREFIX_PROJECT}/phoenix-rtos-ports/check"
+PREFIX_CHECK_SRC="${PREFIX_BUILD}/check"
+
+b_log "Building check test framework"
+
+#
+# Download and unpack
+#
+if [ ! -f "${PREFIX_CHECK}/${CHECK}.tar.gz" ]; then
+	if ! wget "$CHECK_PKG_URL" -O "${PREFIX_CHECK}/${CHECK}.tar.gz" --no-check-certificate; then
+		wget "$CHECK_PKG_MIRROR_URL" -P "$PREFIX_CHECK" --no-check-certificate
+	fi
+fi
+
+if [ ! -d "$PREFIX_CHECK_SRC" ]; then
+	tar xzf "${PREFIX_CHECK}/${CHECK}.tar.gz" -C "$PREFIX_BUILD" && \
+    mv "${PREFIX_BUILD}/${CHECK}" "$PREFIX_CHECK_SRC"
+fi
+
+#
+# Configure
+#
+mkdir -p "${PREFIX_CHECK_SRC}/include"
+if [ ! -f "${PREFIX_CHECK_SRC}/config.h" ]; then
+	CHECK_CFLAGS="-std=gnu99 -I${PREFIX_CHECK_SRC}/include"
+	(cd "$PREFIX_CHECK_SRC" && autoreconf -i -v -f && \
+	PKG_CONFIG="" ./configure CC="$CC" LD="$LD" AR="$AR" STRIP="${CROSS}strip" CFLAGS="$CFLAGS $CHECK_CFLAGS" \
+							  LDFLAGS="$LDFLAGS" --host="${HOST}" --build="x86_64-linux-gnu" --disable-subunit \
+							  --disable-shared --disable-doc --enable-static --libdir="$PREFIX_A" \
+							  --includedir="${PREFIX_CHECK_SRC}/include")
+fi
+
+#
+# Make
+#
+SUBDIRS="lib src . tests" # Run makefiles from this directories
+make -C "$PREFIX_CHECK_SRC"
+make SUBDIRS="$SUBDIRS" doc_DATA="" m4data_DATA="" -C "$PREFIX_CHECK_SRC" install
diff --git a/lwip-tests/build.sh b/lwip-tests/build.sh
new file mode 100755
index 00000000..c2672535
--- /dev/null
+++ b/lwip-tests/build.sh
@@ -0,0 +1,56 @@
+#!/usr/bin/env bash
+
+set -e
+
+b_log "Building lwip-test"
+
+LWIP_CONTRIB_TAG="STABLE-2_1_0_RELEASE"
+LWIP_CONTRIB_PKG_URL="https://git.savannah.nongnu.org/cgit/lwip/lwip-contrib.git/snapshot/lwip-contrib-${LWIP_CONTRIB_TAG}.tar.gz"
+LWIP_CONTRIB_PKG_MIRROR_URL="https://files.phoesys.com/ports/lwip-contrib.tar.gz"
+
+PREFIX_LWIP_TEST="${PREFIX_PROJECT}/phoenix-rtos-ports/lwip-tests"
+PREFIX_LWIP_TEST_BUILD="${PREFIX_BUILD}/lwip-test"
+PREFIX_LWIP_CONTRIB="${PREFIX_LWIP_TEST_BUILD}/contrib-lwip"
+PREFIX_LWIP_CHECK="${PREFIX_LWIP_CONTRIB}/ports/unix/check"
+PREFIX_LWIP_TEST_MARKERS="${PREFIX_LWIP_TEST_BUILD}/markers"
+
+# Set variables used by Makefile
+CHECK_H_PATH="${PREFIX_BUILD}/check/include"
+CONTRIBDIR="${PREFIX_BUILD}/lwip-test/contrib-lwip"
+MBEDTLSDIR="${PREFIX_BUILD}/mbedtls/mbedtls-2.28.0"
+LWIPDIR="${PREFIX_PROJECT}/phoenix-rtos-lwip/lib-lwip/src"
+
+export CHECK_H_PATH CONTRIBDIR MBEDTLSDIR LWIPDIR
+
+#
+# Download and unpack lwip-contrib
+#
+if [ ! -f "${PREFIX_LWIP_TEST}/lwip-contrib.tar.gz" ]; then
+	if ! wget "$LWIP_CONTRIB_PKG_URL" -O "${PREFIX_LWIP_TEST}/lwip-contrib.tar.gz" --no-check-certificate; then
+		wget "$LWIP_CONTRIB_PKG_MIRROR_URL" -P "$PREFIX_LWIP_TEST" --no-check-certificate
+	fi
+fi
+
+mkdir -p "$PREFIX_LWIP_TEST_BUILD"
+if [ ! -d "$PREFIX_LWIP_CONTRIB" ]; then
+	tar xzf "${PREFIX_LWIP_TEST}/lwip-contrib.tar.gz" -C "$PREFIX_LWIP_TEST_BUILD" && \
+	mv "${PREFIX_LWIP_TEST_BUILD}/lwip-contrib-$LWIP_CONTRIB_TAG" "${PREFIX_LWIP_TEST_BUILD}/contrib-lwip"
+fi
+
+#
+# Apply patches
+#
+mkdir -p "$PREFIX_LWIP_TEST_MARKERS"
+for patchfile in "$PREFIX_LWIP_TEST"/patch/*; do
+	if [ ! -f "${PREFIX_LWIP_TEST_MARKERS}/$(basename "$patchfile").applied" ]; then
+		echo "applying patch: $patchfile"
+		patch -d "${PREFIX_LWIP_CONTRIB}/" -p1 < "$patchfile"
+		touch "${PREFIX_LWIP_TEST_MARKERS}/$(basename "$patchfile").applied"
+	fi
+done
+
+make check -C "$PREFIX_LWIP_CHECK"
+"${CROSS}strip" -s "${PREFIX_LWIP_CHECK}/lwip_unittests" -o "${PREFIX_PROG_STRIPPED}/lwip_unittests"
+cp -a "${PREFIX_LWIP_CHECK}/lwip_unittests" "${PREFIX_PROG}/lwip_unittests"
+
+b_install "${PREFIX_PROG_STRIPPED}/lwip_unittests" /bin
diff --git a/lwip-tests/patch/Common-allports.patch b/lwip-tests/patch/Common-allports.patch
new file mode 100644
index 00000000..9c078e17
--- /dev/null
+++ b/lwip-tests/patch/Common-allports.patch
@@ -0,0 +1,24 @@
+--- contrib_orginal/ports/Common.allports.mk	2024-01-09 16:16:39.398560526 +0100
++++ contrib/ports/Common.allports.mk	2024-01-15 15:32:10.693335127 +0100
+@@ -29,11 +29,9 @@
+ # Author: Adam Dunkels <adam@sics.se>
+ #
+ 
+-#CC=gcc
+-#CC=clang
+ CCDEP?=$(CC)
+ 
+-CFLAGS+=-g -DLWIP_DEBUG -Wall -pedantic -Werror \
++CFLAGS+=-g -DLWIP_DEBUG -Wall -pedantic \
+ 	-Wparentheses -Wsequence-point -Wswitch-default \
+ 	-Wextra -Wundef -Wshadow -Wpointer-arith -Wcast-qual \
+ 	-Wc++-compat -Wwrite-strings -Wold-style-definition -Wcast-align \
+@@ -48,7 +46,7 @@
+ #CFLAGS:=$(CFLAGS) -fsanitize=address -fstack-protector -fstack-check -fsanitize=undefined -fno-sanitize=alignment
+ else
+ # we cannot sanitize alignment on x86-64 targets because clang wants 64 bit alignment
+-CFLAGS+= -fsanitize=address -fsanitize=undefined -fno-sanitize=alignment -Wdocumentation -Wno-documentation-deprecated-sync
++# CFLAGS+= -fsanitize=address -fsanitize=undefined -fno-sanitize=alignment -Wdocumentation -Wno-documentation-deprecated-sync
+ endif
+ 
+ CONTRIBDIR?=../../..
diff --git a/lwip-tests/patch/Common.patch b/lwip-tests/patch/Common.patch
new file mode 100644
index 00000000..4d5c8157
--- /dev/null
+++ b/lwip-tests/patch/Common.patch
@@ -0,0 +1,17 @@
+--- contrib_orginal/ports/unix/Common.mk	2024-01-09 16:16:39.402560579 +0100
++++ contrib/ports/unix/Common.mk	2024-01-10 20:01:40.592109932 +0100
+@@ -42,10 +42,12 @@
+ UNIX_COMMON_MK_DIR := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
+ include $(UNIX_COMMON_MK_DIR)../Common.allports.mk
+ 
+-LDFLAGS+=-lutil
++# Util lib not necessary
++# LDFLAGS+=-lutil
+ 
+ UNAME_S:= $(shell uname -s)
+ ifneq ($(UNAME_S),Darwin)
+ # Darwin doesn't have pthreads or POSIX real-time extensions libs
+-LDFLAGS+=-pthread -lrt
++# Phoenix do not need real-time extensions libs and -pthread linker flag
++# LDFLAGS+=-pthread -lrt
+ endif
diff --git a/lwip-tests/patch/Makefile.patch b/lwip-tests/patch/Makefile.patch
new file mode 100644
index 00000000..34aad80e
--- /dev/null
+++ b/lwip-tests/patch/Makefile.patch
@@ -0,0 +1,41 @@
+--- contrib_orginal/ports/unix/check/Makefile	2024-01-09 16:16:39.402560579 +0100
++++ contrib/ports/unix/check/Makefile	2024-01-15 17:00:03.544552858 +0100
+@@ -33,7 +33,7 @@
+ .PHONY: all clean check
+ 
+ # The include path to sys_arch.h and lwipopts.h must be first, so this must be before Common.mk
+-CFLAGS=-DLWIP_NOASSERT_ON_ERROR -I/usr/include/check -I$(LWIPDIR)/../test/unit
++CFLAGS+=-DLWIP_NOASSERT_ON_ERROR -I$(LWIPDIR)/../../include/arch -I$(LWIPDIR)/../../include/default-opts/testsuite -I$(CHECK_H_PATH)
+ 
+ # Ignore 'too many arguments for format' warnings which happen with GCCs
+ # from check 0.15.2 on fail_if/fail_unless macros with text.
+@@ -46,18 +46,21 @@
+ endif
+ 
+ # Prevent compiling sys_arch.c of unix port because unit test provide their own port
+-SYSARCH?=
++PORTDIR = $(LWIPDIR)/../../port
++SYSARCH?=$(wildcard $(PORTDIR)/*.c)
+ include ../Common.mk
+ 
+-LDFLAGS:=-lcheck -lm $(LDFLAGS)
++LDFLAGS+= -lcheck --static
+ 
+ ifneq ($(UNAME_S),Darwin)
+ # check installed via brew on Darwin doesn't have a separate subunit library (must be statically linked)
+-LDFLAGS+=-lsubunit
++# Subunit not ported, tests can work without it
++# LDFLAGS+=-lsubunit
+ endif
+ 
+ TESTDIR=$(LWIPDIR)/../test/unit
+ include $(TESTDIR)/Filelists.mk
++include $(LWIPDIR)/../test/unit/Filelists.mk
+ TESTOBJS=$(notdir $(TESTFILES:.c=.o))
+ 
+ clean:
+@@ -83,4 +86,3 @@
+ endif
+ 
+ check: lwip_unittests
+-	@./lwip_unittests
diff --git a/lwip-tests/patch/config.patch b/lwip-tests/patch/config.patch
new file mode 100644
index 00000000..ea2c90e6
--- /dev/null
+++ b/lwip-tests/patch/config.patch
@@ -0,0 +1,6 @@
+--- contrib_orginal/ports/unix/check/config.h	2024-01-09 16:16:39.402560579 +0100
++++ contrib/ports/unix/check/config.h	2024-01-11 12:56:06.185539301 +0100
+@@ -1,2 +1,2 @@
+ /* Enable this to simplify debugging */
+-/* #define LWIP_UNITTESTS_NOFORK */
++#define LWIP_UNITTESTS_NOFORK
diff --git a/lwip-tests/patch/sio.patch b/lwip-tests/patch/sio.patch
new file mode 100644
index 00000000..bc14cdce
--- /dev/null
+++ b/lwip-tests/patch/sio.patch
@@ -0,0 +1,53 @@
+--- contrib_orginal/ports/unix/port/netif/sio.c	2024-01-09 16:16:39.406560629 +0100
++++ contrib/ports/unix/port/netif/sio.c	2024-01-11 13:57:17.473232246 +0100
+@@ -44,7 +44,7 @@
+ #include <fcntl.h>
+ #include <signal.h>
+ #include <string.h>
+-#include <sys/signal.h>
++#include <signal.h>
+ #include <sys/types.h>
+ 
+ #ifndef LWIP_HAVE_SLIPIF
+@@ -161,11 +161,20 @@
+ 	}
+ 	/* Make the file descriptor asynchronous (the manual page says only
+ 	O_APPEND and O_NONBLOCK, will work with F_SETFL...) */
+-       	if ( fcntl( fd, F_SETFL, FASYNC ) != 0)
++
++
++/*
++ * FASYNC is not standardized by OPEN GROUP and not supported by Phoenix-RTOS
++ * Comment out this code to make it compile, this code is excluded anyway since PPP_SUPPORT is defined
++ */
++
++/*
++	if ( fcntl( fd, F_SETFL, FASYNC ) != 0)
+ 	{
+ 		perror( device );
+ 		exit( -1 );
+ 	}
++*/
+ #else
+        	if ( fcntl( fd, F_SETFL, 0 ) != 0)
+ 	{
+@@ -175,6 +184,19 @@
+ 
+ #endif /* ! (PPP_SUPPORT || LWIP_HAVE_SLIPIF) */
+ 
++
++/*
++ * Phoenix-RTOS patch
++ *
++ * CRTSCTS termios cflag is BSD specific,
++ * This compilation is for Phoenix-RTOS which does not support this flag.
++ * This macro has a chance to be forward compatible if Phoenix-RTOS will support it in the future.
++ */
++#ifndef CRTSCTS
++#define CRTSCTS 0
++#endif
++
++
+ 	tcgetattr( fd,&oldtio ); /* save current port settings */
+ 	/* set new port settings */
+ 	/* see 'man termios' for further settings */