diff --git a/main.go b/main.go
index 89fe202..55ae934 100644
--- a/main.go
+++ b/main.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package main
 
 import (
diff --git a/pkg/cache/cache.go b/pkg/cache/cache.go
index db90505..651cdec 100644
--- a/pkg/cache/cache.go
+++ b/pkg/cache/cache.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package cache
 
 import (
diff --git a/pkg/diff/colors.go b/pkg/diff/colors.go
index e764c13..1eb7e46 100644
--- a/pkg/diff/colors.go
+++ b/pkg/diff/colors.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package diff
 
 import (
diff --git a/pkg/diff/differ.go b/pkg/diff/differ.go
index d978354..ca518e8 100644
--- a/pkg/diff/differ.go
+++ b/pkg/diff/differ.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package diff
 
 import (
diff --git a/pkg/diff/options.go b/pkg/diff/options.go
index 5f6709d..1891b68 100644
--- a/pkg/diff/options.go
+++ b/pkg/diff/options.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package diff
 
 import (
diff --git a/pkg/diff/printer.go b/pkg/diff/printer.go
index 3193002..aa64899 100644
--- a/pkg/diff/printer.go
+++ b/pkg/diff/printer.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package diff
 
 import (
diff --git a/pkg/kubernetes/resolver.go b/pkg/kubernetes/resolver.go
index cccd54a..f1019b1 100644
--- a/pkg/kubernetes/resolver.go
+++ b/pkg/kubernetes/resolver.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package kubernetes
 
 import (
diff --git a/pkg/maputil/maputil.go b/pkg/maputil/maputil.go
index 56e7751..6db92f2 100644
--- a/pkg/maputil/maputil.go
+++ b/pkg/maputil/maputil.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package maputil
 
 import (
diff --git a/pkg/maputil/maputil_test.go b/pkg/maputil/maputil_test.go
index f9853dc..a71ed1d 100644
--- a/pkg/maputil/maputil_test.go
+++ b/pkg/maputil/maputil_test.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package maputil
 
 import (
diff --git a/pkg/maputil/path.go b/pkg/maputil/path.go
index 499a52b..27f18ad 100644
--- a/pkg/maputil/path.go
+++ b/pkg/maputil/path.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package maputil
 
 import (
diff --git a/pkg/maputil/util.go b/pkg/maputil/util.go
index b39e36b..ae9300e 100644
--- a/pkg/maputil/util.go
+++ b/pkg/maputil/util.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package maputil
 
 import "k8s.io/apimachinery/pkg/util/json"
diff --git a/pkg/watcher/watcher.go b/pkg/watcher/watcher.go
index e5807b6..703c29e 100644
--- a/pkg/watcher/watcher.go
+++ b/pkg/watcher/watcher.go
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: 2023 Christoph Mewes
+// SPDX-License-Identifier: MIT
+
 package watcher
 
 import (