diff --git a/mk/test-shell.mk b/mk/test-shell.mk
new file mode 100644
index 00000000..f5f2f4c5
--- /dev/null
+++ b/mk/test-shell.mk
@@ -0,0 +1,21 @@
+-include $(TOPDIR)/config.mk
+
+.PHONY: all
+all: $(TEST)
+
+.PHONY: clean
+clean:
+
+.PHONY: install
+install: all
+	install -d $(DESTDIR)$(TESTSDIR)/$(TESTSSUBDIR)
+	install -m755 $(TEST).sh $(DESTDIR)$(TESTSDIR)/$(TESTSSUBDIR)/$(TEST)
+ifdef EXTRA_FILES
+	for f in $(EXTRA_FILES); do \
+		install -m644 $${f} $(DESTDIR)$(TESTSDIR)/$(TESTSSUBDIR); \
+	done
+endif
+
+.PHONY: uninstall
+uninstall:
+	-rm -f $(DESTDIR)$(TESTSDIR)/$(TESTSSUBDIR)/$(TEST)
diff --git a/tests/libxbps/Makefile b/tests/libxbps/Makefile
index 5b8aa23b..7d0f60e0 100644
--- a/tests/libxbps/Makefile
+++ b/tests/libxbps/Makefile
@@ -10,5 +10,6 @@ SUBDIRS += util
 SUBDIRS += find_pkg_obsoletes
 SUBDIRS += find_pkg_orphans
 SUBDIRS += pkgdb
+SUBDIRS += issue18
 
 include ../../mk/subdir.mk
diff --git a/tests/libxbps/common/Kyuafile b/tests/libxbps/common/Kyuafile
index 8fa94345..59fd8160 100644
--- a/tests/libxbps/common/Kyuafile
+++ b/tests/libxbps/common/Kyuafile
@@ -8,5 +8,6 @@ atf_test_program{name="pkgpattern_match_test"}
 atf_test_program{name="plist_match_test"}
 atf_test_program{name="plist_match_virtual_test"}
 atf_test_program{name="find_pkg_obsoletes_test"}
+atf_test_program{name="issue18_test"}
 include('find_pkg_orphans/Kyuafile')
 include('pkgdb/Kyuafile')
diff --git a/tests/libxbps/issue18/Makefile b/tests/libxbps/issue18/Makefile
new file mode 100644
index 00000000..c5c0e00a
--- /dev/null
+++ b/tests/libxbps/issue18/Makefile
@@ -0,0 +1,7 @@
+TOPDIR = ../../..
+-include $(TOPDIR)/config.mk
+
+TEST = issue18_test
+
+include ../Makefile.inc
+include $(TOPDIR)/mk/test-shell.mk
diff --git a/tests/libxbps/issue18/issue18_test.sh b/tests/libxbps/issue18/issue18_test.sh
new file mode 100755
index 00000000..7a4d9275
--- /dev/null
+++ b/tests/libxbps/issue18/issue18_test.sh
@@ -0,0 +1,32 @@
+#! /usr/bin/env atf-sh
+
+# xbps issue #18.
+# How to reproduce it:
+# 	Generate pkg A-0.1_1 and B-0.1_1.
+#	Install both pkgs.
+#	Generate pkg A-0.2_1: conflicts with B<0.1_2.
+#	Generate pkg B-0.1_2.
+#	Update all packages.
+
+atf_test_case issue18
+
+issue18_head() {
+	atf_set "descr" "xbps issue #18 (https://github.com/xtraeme/xbps/issues/18)"
+}
+
+issue18_body() {
+	mkdir pkg_A pkg_B
+	atf_check 'xbps-create -A noarch -n A-0.1_1 -s "pkg A" pkg_A' 0
+	atf_check 'xbps-create -A noarch -n B-0.1_1 -s "pkg B" pkg_B' 0
+	atf_check 'xbps-rindex -a *.xbps' 0
+	atf_check 'xbps-install -r rootdir --repository=$PWD -y A B' 0
+
+	atf_check 'xbps-create -A noarch -n A-0.2_1 -s "pkg A" --conflicts "B<0.1_2" pkg_A' 0
+	atf_check 'xbps-create -A noarch -n B-0.1_2 -s "pkg B" pkg_B' 0
+	atf_check 'xbps-rindex -a *.xbps' 0
+	atf_check 'xbps-install -r rootdir --repository=$PWD -yu' 0
+}
+
+atf_init_test_cases() {
+	atf_add_test_case issue18
+}