wip: Add Jenkins build pipeline

ci/Jenkinsfile

@@ -0,0 +1,35 @@
+pipeline {
+    parameters {
+        booleanParam 'CLEAN_BUILD'
+    }
+
+    agent {
+        kubernetes {
+            yamlFile 'ci/podTemplate.yaml'
+            yamlMergeStrategy merge()
+            workspaceVolume persistentVolumeClaimWorkspaceVolume(
+                claimName: 'buildroot-kitchenos'
+            )
+            defaultContainer 'build'
+        }
+    }
+
+    stages {
+        stage('Clean') {
+            when {
+                expression {
+                    params.CLEAN_BUILD == 'true'
+                }
+            }
+            steps {
+                sh 'git clean -fdx'
+                sh 'rm -rf buildroot'
+            }
+        }
+        stage('Build') {
+            steps {
+                sh '. ci/build.sh'
+            }
+        }
+    }
+}

ci/build.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+BUILDROOT_REPO=https://gitlab.com/buildroot.org/buildroot.git
+BUILDROOT_BRANCH=2025.05.x
+
+DEFCONFIG=kitchenos_defconfig
+
+if [ ! -d buildroot ]; then
+    git clone "${BUILDROOT_REPO}" --depth=1 -b "${BUILDROOT_BRANCH}"
+else
+    git -C buildroot fetch --depth=1 origin "${BUILDROOT_BRANCH}"
+    git -C buildroot checkout -f "${BUILDROOT_BRANCH}"
+    git -C buildroot merge --ff-only
+fi
+
+if [ ! -f _build/.config ]; then
+    make -C buildroot O="${PWD}"/_build BR2_EXTERNAL="${PWD}" "${DEFCONFIG}"
+fi
+
+make -C _build

ci/podTemplate.yaml

@@ -0,0 +1,17 @@
+spec:
+  containers:
+  - name: build
+    image: git.pyrocufflink.net/containerimages/buildroot
+    resources:
+      limits: &resources
+        cpu: 6
+        memory: 12Gi
+      requests: *resources
+    volumeMounts:
+    - mountPath: /etc/ssh/ssh_known_hosts
+      name: ssh-known-hosts
+      subPath: ssh_known_hosts
+  volumes:
+  - name: ssh-known-hosts
+    configMap:
+      name: ssh-known-hosts