diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
new file mode 100644
index 0000000000000000000000000000000000000000..73feddeb61de1d47fc8630e9f670ee031459ad7e
--- /dev/null
+++ b/.gitlab-ci.yml
@@ -0,0 +1,98 @@
+variables:
+  # This will suppress any download for dependencies and plugins or upload messages which would clutter the console log.
+  # `showDateTime` will show the passed time in milliseconds. You need to specify `--batch-mode` to make this work.
+  MAVEN_OPTS: "-Dhttps.protocols=TLSv1.2 -Dmaven.repo.local=$CI_PROJECT_DIR/.m2/repository -Dorg.slf4j.simpleLogger.log.org.apache.maven.cli.transfer.Slf4jMavenTransferListener=WARN -Dorg.slf4j.simpleLogger.showDateTime=true -Djava.awt.headless=true"
+  # As of Maven 3.3.0 instead of this you may define these options in `.mvn/maven.config` so the same config is used
+  # when running from the command line.
+  #MAVEN_CLI_OPTS: "--batch-mode --errors --fail-at-end --show-version -DinstallAtEnd=true -DdeployAtEnd=true"
+  MAVEN_CLI_OPTS: "--batch-mode --errors --fail-at-end --show-version"
+  # Nexus Deployment settings, please use env vars in Settings -> CI/CD -> Variables.
+  MAVEN_SETTINGS_PATH: ".m2/settings.xml"
+  MAVEN_DEPLOY_OPTS: "--settings=$MAVEN_SETTINGS_PATH"
+  # File for storing the POM project.version
+  VARIABLES_FILE: ./variables.txt
+
+###################
+###  TEMPLATES  ###
+###################
+.webapp: &webapp
+  image: alpine:3.14
+  stage: deploy_deb
+  script:
+    - source $VARIABLES_FILE
+    - 'apk add --no-cache bash'
+    - 'apk add --no-cache curl'
+    - export PLOC="$(ls ./${PPATH}/*.deb)"
+    - DEB_NAME=$PNAME-$PVERSION.deb
+    - echo $DEB_NAME
+    - echo $PKEY
+    - echo $PLOC
+    - 'if [[ $PVERSION =~ .*${PKEY}$ ]]; then'
+    - echo "---A ${PKEY} BUILD IS BEING PERFORMED---"
+    - 'curl -u ${APTLY_USER}:${APTLY_PASSWORD} -X POST --header "Content-Type:multipart/form-data" -F file=@${PLOC} ${APTLY_URL}/files/${DEB_NAME}'
+    - 'curl -u ${APTLY_USER}:${APTLY_PASSWORD} -X POST ${APTLY_URL}/repos/${APTLY_TARGET}/file/${DEB_NAME}'
+    - 'curl -u ${APTLY_USER}:${APTLY_PASSWORD} -X PUT -H "Content-Type: application/json" --data "{}" ${APTLY_URL}/publish/:./indy'
+    - fi
+
+stages:
+  - build_version
+  - deploy_java
+  - deploy_deb
+
+# Cache downloaded dependencies and plugins between builds.
+# To keep cache across branches add 'key: "$CI_JOB_NAME"'
+cache:
+  key: $CI_JOB_NAME
+  paths:
+    - .m2/repository
+
+# Get the project version from main POM file and store it to artifact.
+get_version:
+  image: maven:3.8.3-jdk-8
+  only:
+    - develop
+#    - main
+  stage: build_version
+  script:
+    - 'PVERSION=$(mvn org.apache.maven.plugins:maven-help-plugin:3.1.1:evaluate -Dexpression=project.version -q -DforceStdout)'
+    - echo "export PVERSION=$PVERSION" > $VARIABLES_FILE
+    - echo "Project version from main pom file is $PVERSION"
+  artifacts:
+    name: POM_VERSION
+    paths:
+      - $VARIABLES_FILE
+
+# Build and deploy all the JARs to GWDG Nexus, and build all the DEBs and store DEBs to artifacts.
+build_and_deploy:
+  image: maven:3.8.3-jdk-8
+  only:
+    - develop
+#    - main
+  stage: deploy_java
+  script:
+    - 'mvn $MAVEN_OPTS $MAVEN_CLI_OPTS $MAVEN_DEPLOY_OPTS -U clean deploy -Pdhrep.deb'
+  artifacts:
+    name: WEBAPP_DEB_PACKAGES
+    paths:
+      - ./oaipmh-webapp/target/*.deb
+
+# Deploy DEB files to APTLY repository.
+deploy_oaipmh-webapp_dev:
+  only:
+    - develop
+  variables:
+    PNAME: 'oaipmh-webapp'
+    PPATH: '${PNAME}/target'
+    PKEY: 'SNAPSHOT'
+    APTLY_TARGET: 'indy-snapshots'
+  <<: *webapp
+
+deploy_oaipmh-webapp_prd:
+  only:
+#    - main
+  variables:
+    PNAME: 'oaipmh-webapp'
+    PPATH: '${PNAME}/target'
+    PKEY: 'RELEASE'
+    APTLY_TARGET: 'indy-releases'
+  <<: *webapp
diff --git a/.m2/settings.xml b/.m2/settings.xml
new file mode 100644
index 0000000000000000000000000000000000000000..3fdd646dd2e5a9034694c303e6321db0575e4024
--- /dev/null
+++ b/.m2/settings.xml
@@ -0,0 +1,11 @@
+<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">
+  <servers>
+    <server>
+      <id>${env.NEXUS_REPO_ID}</id>
+      <username>${env.NEXUS_REPO_USER}</username>
+      <password>${env.NEXUS_REPO_PW}</password>
+    </server>
+  </servers>
+</settings>
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000000000000000000000000000000000000..3b549b8e7fe2fa9b60ff7169bc1e2d852a379ecc
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,4 @@
+# 4.0.15-SNAPSHOT
+
+* Move repository, issues, and ci/cd from projects.gwdg.de to gitlab.gwdg.de
+* Implement Gitlab CI/CD workflow
diff --git a/README.md b/README.md
new file mode 100644
index 0000000000000000000000000000000000000000..a0054d834b2bfe384986d2e5135235341b1e1892
--- /dev/null
+++ b/README.md
@@ -0,0 +1,46 @@
+# The DARIAH-DE OAI-PMH Service
+
+## Overview
+
+The OAI-PMH Data Provider Service is used for both TextGrid and the DARIAH-DE Repository, one instance for every installation.
+
+## Technical Information
+
+**TODO**
+
+## Documentation
+
+For service and API documentation please have a look at the [TG-oaipmh Documentation](https://textgridlab.org/doc/services/submodules/oai-pmh/docs_tgrep/index.html), and the [DH-oaipmh Documentation](https://repository.de.dariah.eu/doc/services/submodules/oai-pmh/docs_dhrep/index.html).
+
+## Installation
+
+The service is provided with a Gitlab CI workflow to build .DEB files to be deployed and installed on TextGrid and DARIAH-DE servers.
+
+### Building from GIT using Maven
+
+You can check out the PID Service from our [GIT Repository](https://gitlab.gwdg.de/dariah-de/dariah-de-oaipmh-services), develop or main branch, or get yourself a certain tag, and then use Maven to build the PID Service WAR file:
+
+    git clone https://gitlab.gwdg.de/dariah-de/dariah-de-oaipmh-services.git
+
+... build the WAR packages via:
+
+    mvn clean package
+
+... build the DEB packagea using:
+
+    mvn clean package -Pdhrep.deb
+
+You will get a PID Service WAR and/or DEB file in the folders ./oaipmh-webapp/target.
+
+### Using DEB File
+
+Or you can use a DEB file from the DARIAH-DE [APTLY Repository](https://ci.de.dariah.eu/packages/)
+
+
+## Deploying the PID Service
+
+The service is deployed just by installing the appropriate DEB package.
+
+## Links and References
+
+* [OAI-PMH Service Gitlab page](https://gitlab.gwdg.de/dariah-de/dariah-de-oaipmh-services)
diff --git a/RELEASE.md b/RELEASE.md
new file mode 100644
index 0000000000000000000000000000000000000000..1dc638babe61b140b75b10aaf40cc6d4628d3c81
--- /dev/null
+++ b/RELEASE.md
@@ -0,0 +1,7 @@
+For releasing a new version, please have a look at the [DARIAH-DE Release Management Page] (https://wiki.de.dariah.eu/display/DARIAH3/DARIAH-DE+Release+Management).
+
+Specials in OAI-PMH Service releases are the following:
+
+* Please set the **RELEASE** version to “x.y.z-RELEASE"
+
+* Please set the **SNAPSHOT** version to “x.y.z-SNAPSHOT“
diff --git a/docs_dhrep/index.rst b/docs_dhrep/index.rst
index c61d46e1a7aac0c358e2eb04039965426c337395..d905c42c03a30931bf14c42a87dcc5908b7e9032 100644
--- a/docs_dhrep/index.rst
+++ b/docs_dhrep/index.rst
@@ -218,6 +218,6 @@ License
 See LICENCE_
 
 
-.. _LICENCE: https://projects.gwdg.de/projects/oai-pmh/repository/revisions/master/entry/LICENSE.txt
-.. _oaipmh_sources: https://projects.gwdg.de/projects/oai-pmh/repository
-.. _oaipmh_bugtracking: https://projects.gwdg.de/projects/dariah-de-repository/work_packages
+.. _LICENCE: https://gitlab.gwdg.de/dariah-de/dariah-de-oai-pmh-services/-/blob/main/LICENSE.txt
+.. _oaipmh_sources: https://gitlab.gwdg.de/dariah-de/dariah-de-oai-pmh-services/
+.. _oaipmh_bugtracking: https://gitlab.gwdg.de/dariah-de/dariah-de-oai-pmh-services/-/issues