diff --git a/jobs/templates/swh-docker-dev.groovy.j2 b/jobs/templates/swh-docker-dev.groovy.j2
index e16d703..d35043f 100644
--- a/jobs/templates/swh-docker-dev.groovy.j2
+++ b/jobs/templates/swh-docker-dev.groovy.j2
@@ -1,55 +1,57 @@
 pipeline {
   agent none
 
   options {
     timeout(time: 30, unit: 'MINUTES')
     timestamps()
   }
 
   stages {
     stage('Checkout') {
       agent {
         label "built-in"
       }
 
       steps {
         git url: "https://forge.softwareheritage.org/source/swh-environment.git"
       }
     }
 
     stage('Build Docker images') {
       agent {
         label "built-in"
       }
 
       steps {
         dir('docker') {
           sh 'docker build --pull --no-cache -t swh/stack .'
         }
       }
     }
 
     stage('Run tests') {
       {% filter indent(width=6) %}
         {%- include 'templates/includes/agent-docker.groovy.j2' -%}
       {% endfilter %}
 
       steps {
-        dir('docker') {
-          sh 'python3 -m tox -- -v'
+        lock('docker-agent-host-port-5080') {
+          dir('docker') {
+            sh 'python3 -m tox -- -v'
+          }
         }
       }
     }
   }
 
   post {
     always {
       node('built-in') {
         archiveArtifacts(
           allowEmptyArchive: true,
           artifacts: 'docker/**/*.logs',
         )
       }
     }
   }
 }
diff --git a/jobs/templates/swh-mirror-run-tests.groovy.j2 b/jobs/templates/swh-mirror-run-tests.groovy.j2
index bcd3334..954fa89 100644
--- a/jobs/templates/swh-mirror-run-tests.groovy.j2
+++ b/jobs/templates/swh-mirror-run-tests.groovy.j2
@@ -1,85 +1,87 @@
 pipeline {
   agent none
 
   options {
     // require "Throttle Concurrent Builds" Jenkins plugin
     throttleJobProperty(
       categories: [],
       limitOneJobWithMatchingParams: false,
       maxConcurrentPerNode: 1,
       maxConcurrentTotal: 1,
       paramsToUseForLimit: '',
       throttleEnabled: true,
       throttleOption: 'project',
     )
   }
 
   stages {
     stage('Checkout') {
       agent {
         label "built-in"
       }
 
       steps {
         git url: "https://forge.softwareheritage.org/source/swh-mirror.git"
       }
     }
 
     stage('Build Docker test images') {
       agent {
         label "built-in"
       }
 
       steps {
         dir('images') {
           sh ' ./build_images.sh --write-env-file=image-tag.env'
           stash name: 'image-tag-env', includes: 'image-tag.env'
         }
       }
     }
 
     stage('Run tests') {
       {% filter indent(width=6) %}
         {%- include 'templates/includes/agent-docker.groovy.j2' -%}
       {% endfilter %}
 
       environment {
         SWH_MIRROR_TEST_API_URL = "http://172.17.0.1:5081/api/1"
         SWH_MIRROR_TEST_KAFKA_BROKER = "broker1.journal.staging.swh.network:9093"
         SWH_MIRROR_TEST_OBJSTORAGE_HOST = "objstorage.softwareheritage.org"
       }
 
       steps {
         unstash 'image-tag-env'
-        withCredentials([
-          usernamePassword(credentialsId: 'swh-mirror-test-kafka',
-                           usernameVariable: 'SWH_MIRROR_TEST_KAFKA_USERNAME',
-                           passwordVariable: 'SWH_MIRROR_TEST_KAFKA_PASSWORD'),
-          usernameColonPassword(credentialsId: 'swh-mirror-test-objstorage',
-                                variable: 'SWH_MIRROR_TEST_OBJSTORAGE_CREDENTIALS')]) {
-          sh '''
-          python3 -m pip install -rrequirements-test.txt
-          SWH_MIRROR_TEST_OBJSTORAGE_URL="https://$SWH_MIRROR_TEST_OBJSTORAGE_CREDENTIALS@$SWH_MIRROR_TEST_OBJSTORAGE_HOST/" \
-          python3 -m pytest -v --envfile=image-tag.env --timeout=3600
-          '''
+        lock('docker-agent-host-port-5080') {
+          withCredentials([
+            usernamePassword(credentialsId: 'swh-mirror-test-kafka',
+                             usernameVariable: 'SWH_MIRROR_TEST_KAFKA_USERNAME',
+                             passwordVariable: 'SWH_MIRROR_TEST_KAFKA_PASSWORD'),
+            usernameColonPassword(credentialsId: 'swh-mirror-test-objstorage',
+                                  variable: 'SWH_MIRROR_TEST_OBJSTORAGE_CREDENTIALS')]) {
+            sh '''
+            python3 -m pip install -rrequirements-test.txt
+            SWH_MIRROR_TEST_OBJSTORAGE_URL="https://$SWH_MIRROR_TEST_OBJSTORAGE_CREDENTIALS@$SWH_MIRROR_TEST_OBJSTORAGE_HOST/" \
+            python3 -m pytest -v --envfile=image-tag.env --timeout=3600
+            '''
+          }
         }
       }
     }
   }
 
   post {
     always {
       node('built-in') {
         echo "Clean up Docker stuff"
         sh '''
         docker stack rm swhtest_mirror0 || true
         # Wait for any remaining containers
         docker container ls --filter=label=com.docker.stack.namespace=swhtest_mirror0 --quiet | xargs --no-run-if-empty docker container wait || true
         # Cleanup cruft
         docker config ls --filter=label=com.docker.stack.namespace=swhtest_mirror0 --quiet | xargs --no-run-if-empty docker config rm || true
         docker volume ls --filter=label=com.docker.stack.namespace=swhtest_mirror0 --quiet | xargs --no-run-if-empty docker volume rm || true
         '''
       }
     }
   }
 }