diff --git a/helpers/mongodb b/helpers/mongodb
new file mode 100644
index 000000000..d40d11bfe
--- /dev/null
+++ b/helpers/mongodb
@@ -0,0 +1,355 @@
+#!/bin/bash
+
+# Execute a mongo command
+#
+# example: ynh_mongo_exec --command='db.getMongo().getDBNames().indexOf("wekan")'
+# example: ynh_mongo_exec --command="db.getMongo().getDBNames().indexOf(\"wekan\")"
+#
+# usage: ynh_mongo_exec [--user=user] [--password=password] [--authenticationdatabase=authenticationdatabase] [--database=database] [--host=host] [--port=port] --command="command" [--eval]
+# | arg: -u, --user=						- The user name to connect as
+# | arg: -p, --password=					- The user password
+# | arg: -d, --authenticationdatabase=		- The authenticationdatabase to connect to
+# | arg: -d, --database=					- The database to connect to
+# | arg: -h, --host=						- The host to connect to
+# | arg: -P, --port=						- The port to connect to
+# | arg: -c, --command=						- The command to evaluate
+# | arg: -e, --eval							- Evaluate instead of execute the command.
+#
+#
+ynh_mongo_exec() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=upadhPce
+	local -A args_array=( [u]=user= [p]=password= [a]=authenticationdatabase= [d]=database= [h]=host= [P]=port= [c]=command= [e]=eval )
+	local user
+	local password
+	local authenticationdatabase
+	local database
+	local host
+	local port
+	local command
+	local eval
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+	user="${user:-}"
+	password="${password:-}"
+	authenticationdatabase="${authenticationdatabase:-}"
+	database="${database:-}"
+	host="${host:-}"
+	port="${port:-}"
+	eval=${eval:-0}
+
+	# If user is provided
+	if [ -n "$user" ]
+	then
+		user="--username=$user"
+
+		# If password is provided
+		if [ -n "$password" ]
+		then
+			password="--password=$password"
+		fi
+
+		# If authenticationdatabase is provided
+		if [ -n "$authenticationdatabase" ]
+		then
+			authenticationdatabase="--authenticationDatabase=$authenticationdatabase"
+		else
+			authenticationdatabase="--authenticationDatabase=admin"
+		fi
+	else
+		password=""
+		authenticationdatabase=""
+	fi
+
+	# If host is provided
+	if [ -n "$host" ]
+	then
+		host="--host=$host"
+	fi
+
+	# If port is provided
+	if [ -n "$port" ]
+	then
+		port="--port=$port"
+	fi
+
+	# If eval is not provided
+	if [ $eval -eq 0 ]
+	then
+		# If database is provided
+		if [ -n "$database" ]
+		then
+			database="use $database"
+		else
+			database=""
+		fi
+
+		mongosh --quiet --username $user --password $password --authenticationDatabase $authenticationdatabase --host $host --port $port <<EOF
+$database
+${command}
+quit()
+EOF
+	else
+		# If database is provided
+		if [ -n "$database" ]
+		then
+			database="$database"
+		else
+			database=""
+		fi
+
+		mongosh --quiet $database --username $user --password $password --authenticationDatabase $authenticationdatabase --host $host --port $port --eval="$command"
+	fi
+}
+
+# Drop a database
+#
+# [internal]
+#
+# If you intend to drop the database *and* the associated user,
+# consider using ynh_mongo_remove_db instead.
+#
+# usage: ynh_mongo_drop_db --database=database
+# | arg: -d, --database=	- The database name to drop
+#
+#
+ynh_mongo_drop_db() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=d
+	local -A args_array=( [d]=database= )
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	ynh_mongo_exec --database="$database" --command='db.runCommand({dropDatabase: 1})'
+}
+
+# Dump a database
+#
+# example: ynh_mongo_dump_db --database=wekan > ./dump.bson
+#
+# usage: ynh_mongo_dump_db --database=database
+# | arg: -d, --database=	- The database name to dump
+# | ret: the mongodump output
+#
+#
+ynh_mongo_dump_db() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=d
+	local -A args_array=( [d]=database= )
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	mongodump --quiet --db="$database" --archive
+}
+
+# Create a user
+#
+# [internal]
+#
+# usage: ynh_mongo_create_user --db_user=user --db_pwd=pwd --db_name=name
+# | arg: -u, --db_user=		- The user name to create
+# | arg: -p, --db_pwd=		- The password to identify user by
+# | arg: -n, --db_name=		- Name of the database to grant privilegies
+#
+#
+ynh_mongo_create_user() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=unp
+	local -A args_array=( [u]=db_user= [n]=db_name= [p]=db_pwd= )
+	local db_user
+	local db_name
+	local db_pwd
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	# Create the user and set the user as admin of the db
+	ynh_mongo_exec --database="$db_name" --command='db.createUser( { user: "'${db_user}'", pwd: "'${db_pwd}'", roles: [ { role: "readWrite", db: "'${db_name}'" } ] } );'
+
+	# Add clustermonitoring rights
+	ynh_mongo_exec --database="$db_name" --command='db.grantRolesToUser("'${db_user}'",[{ role: "clusterMonitor", db: "admin" }]);'
+}
+
+# Check if a mongo database exists
+#
+# usage: ynh_mongo_database_exists --database=database
+# | arg: -d, --database=		- The database for which to check existence
+# | exit: Return 1 if the database doesn't exist, 0 otherwise
+#
+#
+ynh_mongo_database_exists() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=d
+	local -A args_array=([d]=database=)
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	if [ $(ynh_mongo_exec --command='db.getMongo().getDBNames().indexOf("'${database}'")' --eval) -lt 0 ]
+	then
+		return 1
+	else
+		return 0
+	fi
+}
+
+# Restore a database
+#
+# example: ynh_mongo_restore_db --database=wekan < ./dump.bson
+#
+# usage: ynh_mongo_restore_db --database=database
+# | arg: -d, --database=	- The database name to restore
+#
+#
+ynh_mongo_restore_db() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=d
+	local -A args_array=( [d]=database= )
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	mongorestore --quiet --db="$database" --archive
+}
+
+# Drop a user
+#
+# [internal]
+#
+# usage: ynh_mongo_drop_user --db_user=user --db_name=name
+# | arg: -u, --db_user=		- The user to drop
+# | arg: -n, --db_name=		- Name of the database
+#
+#
+ynh_mongo_drop_user() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=un
+	local -A args_array=( [u]=db_user= [n]=db_name= )
+	local db_user
+	local db_name
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	ynh_mongo_exec --database="$db_name" --command='db.dropUser("'$db_user'", {w: "majority", wtimeout: 5000})'
+}
+
+# Create a database, an user and its password. Then store the password in the app's config
+#
+# usage: ynh_mongo_setup_db --db_user=user --db_name=name [--db_pwd=pwd]
+# | arg: -u, --db_user=		- Owner of the database
+# | arg: -n, --db_name=		- Name of the database
+# | arg: -p, --db_pwd=		- Password of the database. If not provided, a password will be generated
+#
+# After executing this helper, the password of the created database will be available in $db_pwd
+# It will also be stored as "mongopwd" into the app settings.
+#
+#
+ynh_mongo_setup_db() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=unp
+	local -A args_array=( [u]=db_user= [n]=db_name= [p]=db_pwd= )
+	local db_user
+	local db_name
+	db_pwd=""
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	local new_db_pwd=$(ynh_string_random) # Generate a random password
+	# If $db_pwd is not provided, use new_db_pwd instead for db_pwd
+	db_pwd="${db_pwd:-$new_db_pwd}"
+
+	# Create the user and grant access to the database
+	ynh_mongo_create_user --db_user="$db_user" --db_pwd="$db_pwd" --db_name="$db_name"
+
+	# Store the password in the app's config
+	ynh_app_setting_set --app=$app --key=db_pwd --value=$db_pwd
+}
+
+# Remove a database if it exists, and the associated user
+#
+# usage: ynh_mongo_remove_db --db_user=user --db_name=name
+# | arg: -u, --db_user=		- Owner of the database
+# | arg: -n, --db_name=		- Name of the database
+#
+#
+ynh_mongo_remove_db() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=un
+	local -A args_array=( [u]=db_user= [n]=db_name= )
+	local db_user
+	local db_name
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	if ynh_mongo_database_exists --database=$db_name; then  # Check if the database exists
+		ynh_mongo_drop_db --database=$db_name  # Remove the database
+	else
+		ynh_print_warn --message="Database $db_name not found"
+	fi
+
+	# Remove mongo user if it exists
+	ynh_mongo_drop_user --db_user=$db_user --db_name=$db_name
+}
+
+# Install MongoDB and integrate MongoDB service in YunoHost
+#
+# usage: ynh_install_mongo [--mongo_version=mongo_version]
+# | arg: -m, --mongo_version=		- Version of MongoDB to install
+#
+#
+ynh_install_mongo() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=m
+	local -A args_array=([m]=mongo_version=)
+	local mongo_version
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+	mongo_version="${mongo_version:-$YNH_MONGO_VERSION}"
+
+	ynh_print_info --message="Installing MongoDB Community Edition ..."
+	local mongo_debian_release=$(ynh_get_debian_release)
+
+	if [[ $(cat /proc/cpuinfo) != *"avx"* && "$mongo_version" != "4.4" ]]; then
+    ynh_print_warn --message="Installing Mongo 4.4 as $mongo_version is not compatible with your cpu (see https://docs.mongodb.com/manual/administration/production-notes/#x86_64)."
+    mongo_version="4.4"
+  fi
+  if [[ "$mongo_version" == "4.4" ]]; then
+    ynh_print_warn --message="Switched to buster install as Mongo 4.4 is not compatible with $mongo_debian_release."
+    mongo_debian_release=buster
+  fi
+
+	ynh_install_extra_app_dependencies --repo="deb http://repo.mongodb.org/apt/debian $mongo_debian_release/mongodb-org/$mongo_version main" --package="mongodb-org mongodb-org-server mongodb-org-tools mongodb-mongosh" --key="https://www.mongodb.org/static/pgp/server-$mongo_version.asc"
+	mongodb_servicename=mongod
+
+	# Make sure MongoDB is started and enabled
+	systemctl enable $mongodb_servicename --quiet
+	systemctl daemon-reload --quiet
+	ynh_systemd_action --service_name=$mongodb_servicename --action=restart --line_match="aiting for connections" --log_path="/var/log/mongodb/$mongodb_servicename.log"
+
+	# Integrate MongoDB service in YunoHost
+	yunohost service add $mongodb_servicename --description="MongoDB daemon" --log="/var/log/mongodb/$mongodb_servicename.log"
+
+	# Store mongo_version into the config of this app
+	ynh_app_setting_set --app=$app --key=mongo_version --value=$mongo_version
+}
+
+# Remove MongoDB
+# Only remove the MongoDB service integration in YunoHost for now
+# if MongoDB package as been removed
+#
+# usage: ynh_remove_mongo
+#
+#
+ynh_remove_mongo() {
+	# Only remove the mongodb service if it is not installed.
+	if ! ynh_package_is_installed --package="mongodb*"
+	then
+		ynh_print_info --message="Removing MongoDB service..."
+		mongodb_servicename=mongod
+		# Remove the mongodb service
+		yunohost service remove $mongodb_servicename
+		ynh_secure_remove --file="/var/lib/mongodb"
+		ynh_secure_remove --file="/var/log/mongodb"
+	fi
+}
diff --git a/maintenance/autofix_locale_format.py b/maintenance/autofix_locale_format.py
index 2146267c1..5fa34ad5e 100644
--- a/maintenance/autofix_locale_format.py
+++ b/maintenance/autofix_locale_format.py
@@ -117,7 +117,7 @@ def autofix_orthotypography_and_standardized_words():
     transformations = {s: " " for s in godamn_spaces_of_hell}
     transformations.update(
         {
-            "\.\.\.": "…",
+            r"\.\.\.": "…",
             "https ://": "https://",
         }
     )
diff --git a/src/utils/system.py b/src/utils/system.py
index 57e7eb8f4..27ef98dd1 100644
--- a/src/utils/system.py
+++ b/src/utils/system.py
@@ -63,10 +63,10 @@ def system_virt():
     return system_virt.cache
 
 
-debian_version.cache = None
-debian_version_id.cache = None
-system_arch.cache = None
-system_virt.cache = None
+debian_version.cache = None  # type: ignore[attr-defined]
+debian_version_id.cache = None  # type: ignore[attr-defined]
+system_arch.cache = None  # type: ignore[attr-defined]
+system_virt.cache = None  # type: ignore[attr-defined]
 
 
 def free_space_in_directory(dirpath):