diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ac51a05
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+bazel-*
diff --git a/build/ci/jenkins-presubmit.groovy b/build/ci/jenkins-presubmit.groovy
new file mode 100644
index 0000000..e0fb999
--- /dev/null
+++ b/build/ci/jenkins-presubmit.groovy
@@ -0,0 +1,74 @@
+// This is a 'Jenkinsfile'-style declarative 'Pipeline' definition. It is
+// executed by Jenkins for presubmit checks, ie. checks that run against an
+// open Gerrit change request.
+
+pipeline {
+    agent none
+    stages {
+        stage('Parallel') {
+            parallel {
+                stage('Test') {
+                    agent {
+                        node {
+                            label ""
+                            customWorkspace '/home/ci/monogon'
+                        }
+                    }
+                    steps {
+                        gerritCheck checks: ['jenkins:test': 'RUNNING'], message: "Running on ${env.NODE_NAME}"
+                        sh "git clean -fdx -e '/bazel-*'"
+                        sh "bazel test //..."
+                        sh "bazel test -c dbg //..."
+                    }
+                    post {
+                        success {
+                            gerritCheck checks: ['jenkins:test': 'SUCCESSFUL']
+                        }
+                        unsuccessful {
+                            gerritCheck checks: ['jenkins:test': 'FAILED']
+                        }
+                    }
+                }
+
+                stage('Gazelle') {
+                    agent {
+                        node {
+                            label ""
+                            customWorkspace '/home/ci/monogon'
+                        }
+                    }
+                    steps {
+                        gerritCheck checks: ['jenkins:gazelle': 'RUNNING'], message: "Running on ${env.NODE_NAME}"
+                        sh "git clean -fdx -e '/bazel-*'"
+                        sh "bazel run //:fietsje"
+                        sh "bazel run //:gazelle -- update"
+
+                        script {
+                            def diff = sh script: "git status --porcelain", returnStdout: true
+                            if (diff.trim() != "") {
+                                sh "git diff HEAD"
+                                error """
+                                    Unclean working directory after running gazelle and Fietsje.
+                                    Please run:
+
+                                       \$ bazel run //:fietsje
+                                       \$ bazel run //:gazelle -- update
+
+                                    In your git checkout and amend the resulting diff to this changelist.
+                                """
+                            }
+                        }
+                    }
+                    post {
+                        success {
+                            gerritCheck checks: ['jenkins:gazelle': 'SUCCESSFUL']
+                        }
+                        unsuccessful {
+                            gerritCheck checks: ['jenkins:gazelle': 'FAILED']
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
diff --git a/third_party/go/repositories.bzl b/third_party/go/repositories.bzl
index ca62c5c..f5fd825 100644
--- a/third_party/go/repositories.bzl
+++ b/third_party/go/repositories.bzl
@@ -1,19 +1,3 @@
-#  Copyright 2020 The Monogon Project Authors.
-#
-#  SPDX-License-Identifier: Apache-2.0
-#
-#  Licensed under the Apache License, Version 2.0 (the "License");
-#  you may not use this file except in compliance with the License.
-#  You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing, software
-#  distributed under the License is distributed on an "AS IS" BASIS,
-#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-#  See the License for the specific language governing permissions and
-#  limitations under the License.
-
 load("@bazel_gazelle//:deps.bzl", "go_repository")
 
 def go_repositories():