diff --git a/release-test.sh b/release-test.sh
index e4a77ec..eb5364b 100755
--- a/release-test.sh
+++ b/release-test.sh
@@ -5,65 +5,72 @@ set -x
 
 package=cwltest
 module=cwltest
-repo=https://github.com/common-workflow-language/cwltest.git
+slug=${TRAVIS_PULL_REQUEST_SLUG:=common-workflow-language/cwltool}
+repo=https://github.com/${slug}.git
 run_tests="py.test --pyarg ${module}"
 pipver=8.0.1 # minimum required version of pip
-setupver=20.10.1 # minimum required version of setuptools
+setuptoolsver=20.10.1 # minimum required version of setuptools
 PYVER=${PYVER:=2.7}
 
-rm -Rf testenv${PYVER}_? || /bin/true
+rm -Rf "testenv${PYVER}_"? || /bin/true
 
 export HEAD=${TRAVIS_PULL_REQUEST_SHA:-$(git rev-parse HEAD)}
 if [ "${RELEASE_SKIP}" != "head" ]
 then
-	virtualenv testenv${PYVER}_1 -p python${PYVER}
+	virtualenv "testenv${PYVER}_1" -p "python${PYVER}"
 	# First we test the head
+	# shellcheck source=/dev/null
 	source testenv${PYVER}_1/bin/activate
-	rm testenv${PYVER}_1/lib/python-wheels/setuptools* \
+	rm "testenv${PYVER}_1/lib/python-wheels/setuptools"* \
 		&& pip install --force-reinstall -U pip==${pipver} \
-	        && pip install setuptools==${setupver} wheel
+	        && pip install setuptools==${setuptoolsver} wheel
 	make install-dependencies
 	make test
 	pip uninstall -y ${package} || true; pip uninstall -y ${package} || true; make install
-	mkdir testenv${PYVER}_1/not-${module}
+	mkdir "testenv${PYVER}_1/not-${module}"
 	# if there is a subdir named '${module}' py.test will execute tests
 	# there instead of the installed module's tests
-	pushd testenv${PYVER}_1/not-${module}; ../bin/${run_tests}; popd
+	pushd "testenv${PYVER}_1/not-${module}"
+	# shellcheck disable=SC2086
+	../bin/${run_tests}; popd
 fi
 
-virtualenv testenv${PYVER}_2 -p python${PYVER}
-virtualenv testenv${PYVER}_3 -p python${PYVER}
-virtualenv testenv${PYVER}_4 -p python${PYVER}
-virtualenv testenv${PYVER}_5 -p python${PYVER}
+virtualenv "testenv${PYVER}_2" -p "python${PYVER}"
+virtualenv "testenv${PYVER}_3" -p "python${PYVER}"
+virtualenv "testenv${PYVER}_4" -p "python${PYVER}"
+virtualenv "testenv${PYVER}_5" -p "python${PYVER}"
 
 
 # Secondly we test via pip
 
-pushd testenv${PYVER}_2
+pushd "testenv${PYVER}_2"
+# shellcheck source=/dev/null
 source bin/activate
 rm lib/python-wheels/setuptools* \
 	&& pip install --force-reinstall -U pip==${pipver} \
-        && pip install setuptools==${setupver} wheel
-pip install -e git+${repo}@${HEAD}#egg=${package}
+        && pip install setuptools==${setuptoolsver} wheel
+pip install -e "git+${repo}@${HEAD}#egg=${package}"
 pushd src/${package}
 make install-dependencies
 make dist
 make test
-cp dist/${package}*tar.gz ../../../testenv${PYVER}_3/
-cp dist/${package}*whl ../../../testenv${PYVER}_4/
+cp dist/${package}*tar.gz "../../../testenv${PYVER}_3/"
+cp dist/${package}*whl "../../../testenv${PYVER}_4/"
 pip uninstall -y ${package} || true; pip uninstall -y ${package} || true; make install
 popd # ../.. no subdir named ${proj} here, safe for py.testing the installed module
+# shellcheck disable=SC2086
 bin/${run_tests}
 popd
 
 # Is the source distribution in testenv${PYVER}_2 complete enough to build
 # another functional distribution?
 
-pushd testenv${PYVER}_3/
+pushd "testenv${PYVER}_3/"
+# shellcheck source=/dev/null
 source bin/activate
 rm lib/python-wheels/setuptools* \
 	&& pip install --force-reinstall -U pip==${pipver} \
-        && pip install setuptools==${setupver} wheel
+        && pip install setuptools==${setuptoolsver} wheel
 pip install ${package}*tar.gz
 pip install pytest
 mkdir out
@@ -73,19 +80,25 @@ make dist
 make test
 pip uninstall -y ${package} || true; pip uninstall -y ${package} || true; make install
 mkdir ../not-${module}
-pushd ../not-${module} ; ../../bin/${run_tests}; popd
+pushd ../not-${module}
+# shellcheck disable=SC2086
+../../bin/${run_tests}
+popd
 popd
 popd
 
 # Is the wheel in testenv${PYVER}_2 installable and will it pass the tests
 
-pushd testenv${PYVER}_4/
+pushd "testenv${PYVER}_4/"
+# shellcheck source=/dev/null
 source bin/activate
 rm lib/python-wheels/setuptools* \
 	&& pip install --force-reinstall -U pip==${pipver} \
-        && pip install setuptools==${setupver} wheel
+        && pip install setuptools==${setuptoolsver} wheel
 pip install ${package}*.whl
 pip install pytest
 mkdir not-${module}
-pushd not-${module} ; ../bin/${run_tests}; popd
+pushd not-${module}
+# shellcheck disable=SC2086
+../bin/${run_tests}; popd
 popd