diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 7b24c1ef360433601c298f4066ed8db99b7d8ead..a97f9d932fb0d85332b6f45bec831a0dc93b1486 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -98,7 +98,7 @@ pages:
   only:
     refs:
       - /^release-.*$/i
-      - master
+      - main
     variables:
       # run pages only on gitlab.com
       - $CI_SERVER_HOST == "gitlab.com"
diff --git a/README_SETUP.md b/README_SETUP.md
index 4980b850ecd9fdc10c9fd02c6437aeb5826578b3..9deadefb27e2a93377bafc59242eacc26057b414 100644
--- a/README_SETUP.md
+++ b/README_SETUP.md
@@ -75,7 +75,7 @@ current working directory will be read additionally, if it exists.
 
 Here, we will look at the most common configuration options. For a full and 
 comprehensive description please check out 
-[pycaosdb.ini file](https://gitlab.com/caosdb/caosdb-pylib/-/blob/master/examples/pycaosdb.ini) 
+[pycaosdb.ini file](https://gitlab.com/caosdb/caosdb-pylib/-/blob/main/examples/pycaosdb.ini) 
 You can download this file and use it as a starting point.
 
 
@@ -120,7 +120,7 @@ cacert=/path/to/caosdb.ca.pem
 
 ### Further Settings ##
 As mentioned above, a complete list of options can be found in the 
-[pycaosdb.ini file](https://gitlab.com/caosdb/caosdb-pylib/-/blob/master/examples/pycaosdb.ini) in 
+[pycaosdb.ini file](https://gitlab.com/caosdb/caosdb-pylib/-/blob/main/examples/pycaosdb.ini) in 
 the examples folder of the source code.
 
 ## Try it out ##
@@ -158,4 +158,4 @@ Build documentation in `build/` with `make doc`.
 - `recommonmark`
 
 ### Troubleshooting ##
-If the client is to be executed directly from the `/src` folder, an initial `.\setup.py install --user` must be called.
\ No newline at end of file
+If the client is to be executed directly from the `/src` folder, an initial `.\setup.py install --user` must be called.
diff --git a/RELEASE_GUIDELINES.md b/RELEASE_GUIDELINES.md
index dd6d5af4c43e1eea17c70f29da837c905694fed4..e015b598117abdcd575cf17e2f095fec459a4c4c 100644
--- a/RELEASE_GUIDELINES.md
+++ b/RELEASE_GUIDELINES.md
@@ -24,9 +24,9 @@ guidelines of the CaosDB Project
    variables and set `ISRELEASED` to `True`. Use the possibility to issue
    pre-release versions for testing.
 
-5. Merge the release branch into the master branch.
+5. Merge the release branch into the main branch.
 
-6. Tag the latest commit of the master branch with `v<VERSION>`.
+6. Tag the latest commit of the main branch with `v<VERSION>`.
 
 7. Delete the release branch.
 
@@ -35,8 +35,8 @@ guidelines of the CaosDB Project
 9. Publish the release by executing `./release.sh` with uploads the caosdb
    module to the Python Package Index [pypi.org](https://pypi.org).
 
-10. Merge the master branch back into the dev branch.
+10. Merge the main branch back into the dev branch.
 
-11. After the merge of master to dev, start a new development version by
+11. After the merge of main to dev, start a new development version by
     setting `ISRELEASED` to `False` and by increasing at least the `MIRCO`
     version in [setup.py](./setup.py)
diff --git a/src/doc/configuration.md b/src/doc/configuration.md
index b2de2781d5adff4d59cb3648cd912e142327f676..6e53542f661dcae94622fef24a67cecf7491df9c 100644
--- a/src/doc/configuration.md
+++ b/src/doc/configuration.md
@@ -50,5 +50,5 @@ debugging (which I hope will not be necessary for this tutorial) or if you want
 the internals of the protocol. 
 
 A complete list of options can be found in the 
-[pycaosdb.ini file](https://gitlab.com/caosdb/caosdb-pylib/-/blob/master/examples/pycaosdb.ini) in 
+[pycaosdb.ini file](https://gitlab.com/caosdb/caosdb-pylib/-/blob/main/examples/pycaosdb.ini) in 
 the examples folder of the source code.