diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index e74e5380724ca9013cb1b1978ef0cda9783e3fbf..2c8499e605e6d819f84dc6a87dc7a6a3c326b2c0 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -97,6 +97,7 @@ test:
       - cd .docker
         # here the server and the mysql backend docker are being started
       - CAOSDB_TAG=$CAOSDB_TAG docker-compose  up -d
+      - PYLIB=3286c989
         # the pyinttest docker writes the return value of the tests into the
         # file result
       - /bin/sh ./run.sh
diff --git a/tox.ini b/tox.ini
index 83edefd9bf2376ec6431856cdaed981940435649..072876cd4b675c9332bf78d1d49faf5631d69262 100644
--- a/tox.ini
+++ b/tox.ini
@@ -3,8 +3,10 @@ envlist= py37
 skip_missing_interpreters = true
 [testenv]
 setenv = PASSWORD_STORE_DIR = {env:HOME}/.password-store
+         PYLIB = {env:PYLIB}
 deps=pytest
     nose
     pytest-cov
-commands_pre=pip install ../caosdb-pylib/
+commands_pre = git fetch origin && git checkout $PYLIB
+			   pip install ../caosdb-pylib/
 commands=pytest --cov=caosdb -vvx {posargs}