diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
new file mode 100644
index 0000000..2da62db
--- /dev/null
+++ b/.gitlab-ci.yml
@@ -0,0 +1,71 @@
+# Redmine plugin for Custom Workflows
+#
+# Copyright © 2015-19 Anton Argirov
+# Copyright © 2019-21 Karel Pičman <karel.picman@kontron.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+image: docker:stable
+
+before_script:
+  - docker info
+
+stages:
+  - custom_workflows
+
+mariadb:
+  stage: custom_workflows
+  tags:
+    - docker
+  script:
+    # Create an image
+    - docker build -t custom_workflows_image -f Dockerfile .
+    # Run the container, optionally run some tests/apps in it
+    - docker rm -f custom_workflows_container 2>/dev/null || true
+    - docker run --name custom_workflows_container custom_workflows_image bash ./test/ci/ci.sh mariadb
+    # Remove the container
+    - docker rm custom_workflows_container
+    # Remove image
+    - docker rmi custom_workflows_image
+
+postgres:
+  stage: custom_workflows
+  tags:
+    - docker
+  script:
+    # Create an image
+    - docker build -t custom_workflows_image -f Dockerfile .
+    # Run the container, optionally run some tests/apps in it
+    - docker rm -f custom_workflows_container 2>/dev/null || true
+    - docker run --name custom_workflows_container custom_workflows_image bash ./test/ci/ci.sh postgres
+    # Remove the container
+    - docker rm custom_workflows_container
+    # Remove image
+    - docker rmi custom_workflows_image
+
+sqlite3:
+  stage: custom_workflows
+  tags:
+    - docker
+  script:
+    # Create an image
+    - docker build -t custom_workflows_image -f Dockerfile .
+    # Run the container, optionally run some tests/apps in it
+    - docker rm -f custom_workflows_container 2>/dev/null || true
+    - docker run --name custom_workflows_container custom_workflows_image bash ./test/ci/ci.sh sqlite3
+    # Remove the container
+    - docker rm custom_workflows_container
+    # Remove image
+    - docker rmi custom_workflows_image
diff --git a/.travis.yml b/Dockerfile
similarity index 51%
rename from .travis.yml
rename to Dockerfile
index 0bf6884..b1d1f09 100644
--- a/.travis.yml
+++ b/Dockerfile
@@ -1,5 +1,3 @@
-# encoding: utf-8
-#
 # Redmine plugin for Custom Workflows
 #
 # Copyright © 2015-19 Anton Argirov
@@ -18,46 +16,11 @@
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# The Docker file definition for GitLab Continous Integration
 
-language: ruby
-
-sudo: true
-
-dist: xenial
-
-rvm:      
-  - 2.5
-
-before_install:
-  - mysql -e 'CREATE DATABASE IF NOT EXISTS test CHARACTER SET utf8mb4;'
-  - psql -c 'create database test;' -U postgres
-  - export WORKSPACE=`pwd`/workspace
-  - export PATH_TO_CUSTOM_WORKFLOWS=`pwd`
-  - export PATH_TO_REDMINE=$WORKSPACE/redmine
-  - export BUNDLE_GEMFILE=$PATH_TO_REDMINE/Gemfile
-  - mkdir -p ${WORKSPACE}
-  - cp -f ./test/ci/${DB}.yml ${WORKSPACE}/database.yml
-  - bash -x ./test/ci/redmine_install.sh -c
-  - bash -x ./test/ci/redmine_install.sh -i
-
-install:
-
-script:
-  - bash -x ./test/ci/redmine_install.sh -t
-
-after_script:
-  - bash -x ./test/ci/redmine_install.sh -u
-
-env:
-  - DB=sqlite
-  - DB=mysql
-  - DB=postgres
-
-cache: bundler
-
-services:
-  - mysql
-  - postgresql
-
-addons:
-  mariadb: '10.3'
+FROM debian:latest
+RUN apt-get update
+RUN apt-get -qq install mariadb-server postgresql sqlite3 libsqlite3-dev ruby ruby-dev build-essential libmariadb-dev libpq-dev subversion git
+COPY . /app
+WORKDIR /app
diff --git a/test/ci/ci.sh b/test/ci/ci.sh
new file mode 100644
index 0000000..68b5047
--- /dev/null
+++ b/test/ci/ci.sh
@@ -0,0 +1,109 @@
+#!/bin/bash
+# Redmine plugin for Custom Workflows
+#
+# Copyright © 2015-19 Anton Argirov
+# Copyright © 2019-21 Karel Pičman <karel.picman@kontron.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# The script for GitLab Continuous Integration
+
+# Exit if any command fails
+set -e
+
+# Display the first argument (DB engine)
+echo $1
+
+# Variables
+REDMINE_REPO=http://svn.redmine.org/redmine/branches/4.2-stable/
+REDMINE_PATH=/opt/redmine
+
+# Init
+rm -rf "${REDMINE_PATH}"
+
+# Clone Redmine
+svn export "${REDMINE_REPO}" "${REDMINE_PATH}"
+
+# Add the plugin
+ln -s /app "${REDMINE_PATH}"/plugins/redmine_custom_workflows
+
+# Prepare the database
+cp "./test/ci/$1.yml" "${REDMINE_PATH}/config/database.yml"
+case $1 in
+
+  mariadb)
+    /etc/init.d/$1 start
+    mariadb -e "CREATE DATABASE IF NOT EXISTS test CHARACTER SET utf8mb4"
+    mariadb -e "CREATE USER 'redmine'@'localhost' IDENTIFIED BY 'redmine'";
+    mariadb -e "GRANT ALL PRIVILEGES ON test.* TO 'redmine'@'localhost'";
+    ;;
+
+  postgres)
+    /etc/init.d/$1ql start
+    su -c "psql -c \"CREATE ROLE redmine LOGIN ENCRYPTED PASSWORD 'redmine' NOINHERIT VALID UNTIL 'infinity';\"" postgres
+    su -c "psql -c \"CREATE DATABASE test WITH ENCODING='UTF8' OWNER=redmine;\"" postgres
+    su -c "psql -c \"ALTER USER redmine CREATEDB;\"" postgres
+    ;;
+
+  sqlite3)
+    ;;
+
+  *)
+    echo 'Missing argument'
+    exit 1
+    ;;
+esac
+
+# Install Redmine
+cd "${REDMINE_PATH}"
+gem install bundler
+RAILS_ENV=test bundle config set --local without 'development'
+RAILS_ENV=test bundle install
+RAILS_ENV=test bundle exec rake generate_secret_token
+RAILS_ENV=test bundle exec rake db:migrate
+RAILS_ENV=test bundle exec rake redmine:plugins:migrate
+RAILS_ENV=test REDMINE_LANG=en bundle exec rake redmine:load_default_data
+
+# Run Redmine tests
+#RAILS_ENV=test bundle exec rake test
+
+# Run Custom Workflows' tests
+bundle exec rake redmine:plugins:test:units NAME=redmine_custom_workflows RAILS_ENV=test
+bundle exec rake redmine:plugins:test:functionals NAME=redmine_custom_workflows RAILS_ENV=test
+bundle exec rake redmine:plugins:test:integration NAME=redmine_custom_workflows RAILS_ENV=test
+
+# Clean up database from the plugin changes
+bundle exec rake redmine:plugins:migrate NAME=redmine_custom_workflows VERSION=0 RAILS_ENV=test
+
+case $1 in
+
+  mariadb)
+    /etc/init.d/$1 stop
+    ;;
+
+  postgres)
+    /etc/init.d/$1ql stop
+    ;;
+
+  sqlite3)
+    ;;
+
+  *)
+    echo 'Missing argument'
+    exit 1
+    ;;
+esac
+
+echo "$1 Okay"
diff --git a/test/ci/mariadb.yml b/test/ci/mariadb.yml
new file mode 100644
index 0000000..ed92efd
--- /dev/null
+++ b/test/ci/mariadb.yml
@@ -0,0 +1,28 @@
+# Redmine plugin for Custom Workflows
+#
+# Copyright © 2015-19 Anton Argirov
+# Copyright © 2019-21 Karel Pičman <karel.picman@kontron.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# MariDb file definition for GitLab Continous Integration
+
+test:
+  adapter: mysql2
+  database: test
+  username: redmine
+  password: "redmine"
+  encoding: utf8mb4
+  collation: utf8mb4_unicode_ci
\ No newline at end of file
diff --git a/test/ci/mysql.yml b/test/ci/mysql.yml
deleted file mode 100644
index 01381c9..0000000
--- a/test/ci/mysql.yml
+++ /dev/null
@@ -1,7 +0,0 @@
-
-test:
-  adapter: mysql2
-  database: test
-  username: root
-  encoding: utf8mb4
-  collation: utf8mb4_unicode_ci
\ No newline at end of file
diff --git a/test/ci/postgres.yml b/test/ci/postgres.yml
index 0269c6e..d4739f9 100644
--- a/test/ci/postgres.yml
+++ b/test/ci/postgres.yml
@@ -1,5 +1,27 @@
+# Redmine plugin for Custom Workflows
+#
+# Copyright © 2015-19 Anton Argirov
+# Copyright © 2019-21 Karel Pičman <karel.picman@kontron.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# PosgreSQL file definition for GitLab Continous Integration
 
 test:
   adapter: postgresql
   database: test
-  encoding: utf8
\ No newline at end of file
+  username: redmine
+  password: redmine
+  host: localhost
\ No newline at end of file
diff --git a/test/ci/redmine_install.sh b/test/ci/redmine_install.sh
deleted file mode 100644
index 6feb629..0000000
--- a/test/ci/redmine_install.sh
+++ /dev/null
@@ -1,98 +0,0 @@
-#!/bin/bash
-# encoding: utf-8
-#
-# Redmine plugin for Custom Workflows
-#
-# Copyright © 2015-19 Anton Argirov
-# Copyright © 2019-21 Karel Pičman <karel.picman@kontron.com>
-#
-# This program is free software; you can redistribute it and/or
-# modify it under the terms of the GNU General Public License
-# as published by the Free Software Foundation; either version 2
-# of the License, or (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
-
-export REDMINE_GIT_REPO=git://github.com/redmine/redmine.git
-export REDMINE_GIT_TAG=4.1-stable
-
-clone()
-{
-  # Exit if the cloning fails
-  set -e
-
-  rm -rf ${PATH_TO_REDMINE}
-  git clone -b ${REDMINE_GIT_TAG} --depth=100 --quiet ${REDMINE_GIT_REPO} ${PATH_TO_REDMINE}
-}
-
-test()
-{
-  # Exit if a test fails
-  set -e
-
-  cd ${PATH_TO_REDMINE}
-
-  # Run tests within application
-  bundle exec rake redmine:plugins:test:units NAME=redmine_custom_workflows RAILS_ENV=test
-  bundle exec rake redmine:plugins:test:functionals NAME=redmine_custom_workflows RAILS_ENV=test
-}
-
-uninstall()
-{
-  # Exit if the migration fails
-  set -e
-
-  cd ${PATH_TO_REDMINE}
-
-  # clean up database
-  bundle exec rake redmine:plugins:migrate NAME=redmine_custom_workflows VERSION=0 RAILS_ENV=test
-}
-
-install()
-{
-  # Exit if the installation fails
-  set -e
-
-  # cd to redmine folder
-  cd ${PATH_TO_REDMINE}
-  echo current directory is `pwd`
-
-  # Create a link to the Custom Workflows plugin
-  ln -sf ${PATH_TO_CUSTOM_WORKFLOWS} plugins/redmine_custom_workflows
-
-  # Copy database.yml
-  cp ${WORKSPACE}/database.yml config/
-
-  # Install gems
-  # Not ideal, but at present Travis-CI will not install with xapian enabled:
-  bundle install --without rmagick development RAILS_ENV=test
-
-  # Run Redmine database migrations
-  bundle exec rake db:migrate --trace RAILS_ENV=test
-
-  # Load Redmine database default data  
-  bundle exec rake redmine:load_default_data REDMINE_LANG=en RAILS_ENV=test
-
-  # generate session store/secret token
-  bundle exec rake generate_secret_token RAILS_ENV=test
-  
-  # Run the plugin database migrations
-  bundle exec rake redmine:plugins:migrate RAILS_ENV=test
-}
-
-while getopts :ictu opt
-do case "$opt" in
-  c) clone; exit 0;;
-  i) install; exit 0;;
-  t) test; exit 0;;
-  u) uninstall; exit 0;;
-  [?]) echo "i: install; c: clone redmine; t: run tests; u: uninstall";;
-  esac
-done
\ No newline at end of file
diff --git a/test/ci/sqlite.yml b/test/ci/sqlite.yml
deleted file mode 100644
index f9e3c7c..0000000
--- a/test/ci/sqlite.yml
+++ /dev/null
@@ -1,5 +0,0 @@
-
-test:
-  adapter: sqlite3
-  database: db/test.sqlite3
-  timeout: 500
\ No newline at end of file
diff --git a/test/ci/sqlite3.yml b/test/ci/sqlite3.yml
new file mode 100644
index 0000000..8dce453
--- /dev/null
+++ b/test/ci/sqlite3.yml
@@ -0,0 +1,24 @@
+# Redmine plugin for Custom Workflows
+#
+# Copyright © 2015-19 Anton Argirov
+# Copyright © 2019-21 Karel Pičman <karel.picman@kontron.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# SQLite file definition for GitLab Continous Integration
+
+test:
+  adapter: sqlite3
+  database: db/redmine.sqlite3
\ No newline at end of file