diff --git a/Makefile.am b/Makefile.am
index 7bfa767..9e7bba1 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -46,11 +46,14 @@ endif
 endif
 
 if cwWEB
+
+  AM_CXXFLAGS += --std=c++11
+
   FFT_DIR   = $(HOME)/src/fftw-3.3.8/build
   FFT_DIR_D   = $(FFT_DIR)/d
   FFT_DIR_S   = $(FFT_DIR)/s
 
-  AM_CXXFLAGS += --std=c++11
+
   AM_CPPFLAGS += -I$(FFT_DIR)/include -I$(FFT_DIR_D)/include -I$(FFT_DIR_S)/include
   AM_LDFLAGS  += -L$(FFT_DIR)/lib     -L$(FFT_DIR_D)/lib     -L$(FFT_DIR_S)/lib
 else
@@ -68,7 +71,15 @@ src_cwtest_cwtest_SOURCES   = src/cwtest/main.cpp
 
 # 1) autoconfig manual recommends setting direct referenes to non-3rd party libraries rather than using -L and -l
 # 2) -ldl is required for dlopen(),dlclose() ...
-src_cwtest_cwtest_LDADD     = libcw.la  -lpthread -ldl -lfftw3 -lfftw3f
+src_cwtest_cwtest_LDADD     = libcw.la  -lpthread -ldl
+
+if cwFFTW
+  src_cwtest_cwtest_LDADD += -lfftw3 -lfftw3f
+endif
+
+if cwWEB
+  src_cwtest_cwtest_LDADD += -lfftw3 -lfftw3f
+endif
 
 if cwWEBSOCK
   AM_CPPFLAGS += -I$(WS_DIR)/include
diff --git a/build/linux/debug/build.sh b/build/linux/debug/build.sh
index b9a24a8..74c8774 100755
--- a/build/linux/debug/build.sh
+++ b/build/linux/debug/build.sh
@@ -15,11 +15,11 @@ cd ${curdir}
 # To enable websock: --enable-websock \
 # To enable alsa: --enable-alsa \
     
-../../../configure --prefix=${curdir} --enable-debug --enable-alsa \
+../../../configure --prefix=${curdir}  --enable-debug --enable-alsa \
 CFLAGS="-g -Wall" \
 CXXFLAGS="-g -Wall" \
-CPPFLAGS= \
-LDFLAGS= \
+CPPFLAGS="-I${HOME}/sdk/libwebsockets/build/out/include" \
+LDFLAGS="-L${HOME}/sdk/libwebsockets/build/out/lib" \
 LIBS=
 
 
diff --git a/configure.ac b/configure.ac
index 9a8fb49..189b6e5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -22,10 +22,6 @@ AC_PROG_CXX
 
 AM_PROG_CC_C_O
 
-# Checks for libraries.
-# AC_CHECK_LIB([cairo],[cairo_debug_reset_static_data],[AC_MSG_RESULT([The 'cairo' library was found.])],[AC_MSG_ERROR([The 'cairo' library was not found.])])
-#TODO: add more library checks 
-
 
 # Checks for header files.
 AC_CHECK_HEADERS([arpa/inet.h fcntl.h float.h limits.h mach/mach.h netinet/in.h stdlib.h string.h sys/ioctl.h sys/socket.h sys/time.h termios.h unistd.h])
@@ -46,6 +42,16 @@ AC_FUNC_REALLOC
 AC_FUNC_STRTOD
 AC_CHECK_FUNCS([clock_gettime floor memmove memset mkdir pow rint select socket sqrt strcasecmp strchr strcspn strerror strspn strstr strtol])
 
+# Checks for libraries.
+fftw=false
+AC_CHECK_LIB([fftw3],[fftw_malloc],[fftw=true],[])
+AM_CONDITIONAL([cwFFTW],[test x"${fftw}" = xtrue])
+
+if test x"$fftw" = xtrue; then
+AC_DEFINE([cwFFTW], 1,[Use libfftw3.])
+fi
+
+echo "fftw='${fftw}'"
 
 # The following is a custom macro in ./m4/os_type.m4
 # be sure to also set "ACLOCAL_AMFLAGS = -I m4" in ./Makefile.am