diff --git a/Makefile b/Makefile
index 906ccdd..6b45f31 100644
--- a/Makefile
+++ b/Makefile
@@ -10,22 +10,16 @@ OSOURCE       = $(sort $(wildcard ${PROJECT}/*.c) \
 SOURCE_FILTER =
 
 ifneq (${WITH_SQLITE},0)
-INCS     += $(SQLITE_INC)
-LIBS     += $(SQLITE_LIB)
 CPPFLAGS += -DWITH_SQLITE
 else
 SOURCE_FILTER += ${PROJECT}/database-sqlite.c
 endif
 
 ifneq ($(WITH_MAGIC),0)
-INCS     += $(MAGIC_INC)
-LIBS     += $(MAGIC_LIB)
 CPPFLAGS += -DWITH_MAGIC
 endif
 
 ifneq ($(WITH_SYNCTEX),0)
-INCS     += $(SYNCTEX_INC)
-LIBS     += $(SYNCTEX_LIB)
 CPPFLAGS += -DWITH_SYNCTEX
 endif
 
diff --git a/config.mk b/config.mk
index 68b399a..625897e 100644
--- a/config.mk
+++ b/config.mk
@@ -74,38 +74,58 @@ PLUGINDIR ?= ${LIBDIR}/zathura
 LOCALEDIR ?= ${PREFIX}/share/locale
 
 # libs
-GTK_INC ?= $(shell ${PKG_CONFIG} --cflags gtk+-3.0)
-GTK_LIB ?= $(shell ${PKG_CONFIG} --libs gtk+-3.0)
+ifeq (${GTK_INC}-${GTK_LIB},-)
+PKG_CONFIG_LIBS += gtk+-3.0
+else
+INCS += ${GTK_INC}
+LIBS += ${GTK_LIB}
+endif
 
-GTHREAD_INC ?= $(shell ${PKG_CONFIG} --cflags gthread-2.0)
-GTHREAD_LIB ?= $(shell ${PKG_CONFIG} --libs   gthread-2.0)
+ifeq (${GLIB_INC}-${GLIB_LIB},-)
+PKG_CONFIG_LIBS += gthread-2.0 gmodule-no-export-2.0 glib-2.0
+else
+INCS += ${GLIB_INC}
+LIBS += ${GLIB_LIB}
+endif
 
-GMODULE_INC ?= $(shell ${PKG_CONFIG} --cflags gmodule-no-export-2.0)
-GMODULE_LIB ?= $(shell ${PKG_CONFIG} --libs   gmodule-no-export-2.0)
-
-GLIB_INC ?= $(shell ${PKG_CONFIG} --cflags glib-2.0)
-GLIB_LIB ?= $(shell ${PKG_CONFIG} --libs glib-2.0)
-
-GIRARA_INC ?= $(shell ${PKG_CONFIG} --cflags girara-gtk3)
-GIRARA_LIB ?= $(shell ${PKG_CONFIG} --libs girara-gtk3)
+ifeq (${GIRARA_INC}-${GIRARA_LIB},-)
+PKG_CONFIG_LIBS += girara-gtk3
+else
+INCS += ${GIRARA_INC}
+LIBS += ${GIRARA_LIB}
+endif
 
 ifneq (${WITH_SQLITE},0)
-SQLITE_INC ?= $(shell ${PKG_CONFIG} --cflags sqlite3)
-SQLITE_LIB ?= $(shell ${PKG_CONFIG} --libs sqlite3)
+ifeq (${SQLITE_INC}-${SQLITE_LIB},-)
+PKG_CONFIG_LIBS += sqlite3
+else
+INCS += ${SQLITE_INC}
+LIBS += ${SQLITE_LIB}
+endif
 endif
 
 ifneq (${WITH_MAGIC},0)
 MAGIC_INC ?=
 MAGIC_LIB ?= -lmagic
+
+INCS += ${MAGIC_INC}
+LIBS += ${MAGIC_LIB}
 endif
 
 ifneq ($(WITH_SYNCTEX),0)
-SYNCTEX_INC ?= $(shell ${PKG_CONFIG} --cflags synctex)
-SYNCTEX_LIB ?= $(shell ${PKG_CONFIG} --libs synctex)
+ifeq (${SYNCTEX_INC}-${SYNCTEX_LIB},-)
+PKG_CONFIG_LIBS += synctex
+else
+INCS += ${SYNCTEX_INC}
+LIBS += ${SYNCTEX_LIB}
+endif
 endif
 
-INCS = ${GIRARA_INC} ${GTK_INC} ${GTHREAD_INC} ${GMODULE_INC} ${GLIB_INC}
-LIBS = ${GIRARA_LIB} ${GTK_LIB} ${GTHREAD_LIB} ${GMODULE_LIB} ${GLIB_LIB} -lpthread -lm
+ifneq (${PKG_CONFIG_LIBS},)
+INCS += $(shell ${PKG_CONFIG} --cflags ${PKG_CONFIG_LIBS})
+LIBS += $(shell ${PKG_CONFIG} --libs ${PKG_CONFIG_LIBS})
+endif
+LIBS += -lpthread -lm
 
 # pre-processor flags
 CPPFLAGS += -D_FILE_OFFSET_BITS=64
diff --git a/tests/Makefile b/tests/Makefile
index c58f851..99e8da7 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -15,22 +15,16 @@ OBJECTS_GCOV  = $(addprefix ${BUILDDIR_GCOV}/,${SOURCE:.c=.o})
 FILTER = %/main.o
 
 ifneq (${WITH_SQLITE},0)
-INCS     += $(SQLITE_INC)
-LIBS     += $(SQLITE_LIB)
 CPPFLAGS += -DWITH_SQLITE
 else
 FILTER += %/database-sqlite.o
 endif
 
 ifneq ($(WITH_MAGIC),0)
-INCS     += $(MAGIC_INC)
-LIBS     += $(MAGIC_LIB)
 CPPFLAGS += -DWITH_MAGIC
 endif
 
 ifneq ($(WITH_SYNCTEX),0)
-INCS   += $(SYNCTEX_INC)
-LIBS   += $(SYNCTEX_LIB)
 CPPFLAGS += -DWITH_SYNCTEX
 endif