diff --git a/config/crd/apiextensions.k8s.io/v1/base/sync.appuio.ch_syncconfigs.yaml b/config/crd/apiextensions.k8s.io/v1/base/sync.appuio.ch_syncconfigs.yaml
index c3c2b171..3a2c072a 100644
--- a/config/crd/apiextensions.k8s.io/v1/base/sync.appuio.ch_syncconfigs.yaml
+++ b/config/crd/apiextensions.k8s.io/v1/base/sync.appuio.ch_syncconfigs.yaml
@@ -12,6 +12,7 @@ spec:
     listKind: SyncConfigList
     plural: syncconfigs
     singular: syncconfig
+  preserveUnknownFields: false
   scope: Namespaced
   versions:
   - additionalPrinterColumns:
diff --git a/generate.go b/generate.go
index 6980d05d..a0cb4b3b 100644
--- a/generate.go
+++ b/generate.go
@@ -3,4 +3,4 @@
 package main
 
 //go:generate go run sigs.k8s.io/controller-tools/cmd/controller-gen object:headerFile="hack/boilerplate.go.txt" paths="./..."
-//go:generate go run sigs.k8s.io/controller-tools/cmd/controller-gen rbac:roleName=manager-role webhook paths="./..." output:crd:artifacts:config=${CRD_ROOT_DIR}/v1/base crd:crdVersions=v1
+//go:generate go run sigs.k8s.io/controller-tools/cmd/controller-gen rbac:roleName=manager-role webhook paths="./..." output:crd:artifacts:config=${CRD_ROOT_DIR}/v1/base crd:crdVersions=v1,deprecatedV1beta1CompatibilityPreserveUnknownFields=false