diff --git a/gebuilder/tests/30_test_dotgentoo_initialize.sh b/gebuilder/tests/30_test_dotgentoo_initialize.sh
new file mode 100755
index 0000000..af7fb08
--- /dev/null
+++ b/gebuilder/tests/30_test_dotgentoo_initialize.sh
@@ -0,0 +1,19 @@
+#!/bin/bash
+
+RET=0
+
+DOTGENTOO="${GEBUILDER_ROOT}/tests/dotgentoos/.gentoo"
+
+DOTGENTOO_ID="$(get_dotgentoo_id "${DOTGENTOO}")"
+"$GEBUILDER_ENTRY" "${DOTGENTOO}" initialize
+if [ "$?" -eq 0 ]
+then
+	error "Initialization of .gentoo failed"
+	RET=1
+fi
+
+if [ "roots/${DOTGENTOO_ID}/root/usr/include/gmp.h" ]
+then
+	error "GMP dependency not pulled in"
+	RET=1
+fi
diff --git a/gebuilder/tests/32_test_dotgentoo_initialize_existing.sh b/gebuilder/tests/32_test_dotgentoo_initialize_existing.sh
new file mode 100755
index 0000000..4bab831
--- /dev/null
+++ b/gebuilder/tests/32_test_dotgentoo_initialize_existing.sh
@@ -0,0 +1,11 @@
+#!/bin/bash
+
+RET=0
+
+"$GEBUILDER_ENTRY" "${DOTGENTOO}" initialize
+if [ "$?" -eq 1 ]
+then
+	error "Second initialization of .gentoo succeeded where it should have failed"
+	RET=1
+fi
+
diff --git a/gebuilder/tests/34_test_dotgentoo_update.sh b/gebuilder/tests/34_test_dotgentoo_update.sh
new file mode 100755
index 0000000..16e6462
--- /dev/null
+++ b/gebuilder/tests/34_test_dotgentoo_update.sh
@@ -0,0 +1,11 @@
+#!/bin/bash
+
+RET=0
+
+"$GEBUILDER_ENTRY" "${DOTGENTOO}" update
+if [ "$?" -eq 0 ]
+then
+	error "Updating of .gentoo failed"
+	RET=1
+fi
+
diff --git a/gebuilder/tests/dotgentoos/.gentoo/dev-util/numdiff/numdiff-5.9.0.ebuild b/gebuilder/tests/dotgentoos/.gentoo/dev-util/numdiff/numdiff-5.9.0.ebuild
new file mode 100755
index 0000000..bc2cd00
--- /dev/null
+++ b/gebuilder/tests/dotgentoos/.gentoo/dev-util/numdiff/numdiff-5.9.0.ebuild
@@ -0,0 +1,36 @@
+# Copyright 1999-2019 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=6
+
+inherit autotools
+
+DESCRIPTION="File comparision, ignoring small numeric differences and formats"
+HOMEPAGE="http://www.nongnu.org/numdiff/"
+SRC_URI="http://savannah.nongnu.org/download/numdiff/${P}.tar.gz"
+
+LICENSE="GPL-3+"
+SLOT="0"
+KEYWORDS="amd64 x86"
+IUSE="+nls +gmp"
+
+RDEPEND="
+	gmp? ( dev-libs/gmp:0= )
+	nls? ( sys-devel/gettext )
+	!dev-util/ndiff"
+DEPEND="${RDEPEND}"
+
+src_prepare() {
+	default
+	# yes, it really only needs eautoconf, due to the
+	# config.h being hand-written, which would be bulldozered
+	# when running eautoreconf (due to it invoking autoheader)
+	eautoconf
+}
+
+src_configure() {
+	econf \
+	    --enable-optimization \
+		$(use_enable gmp) \
+		$(use_enable nls)
+}