diff --git a/Makefile b/Makefile
index e4f9d619b9f97deb2be2e1448d584e96e6114ca4..61f670de557dba86523332b5e060512048756e21 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,7 @@
+## Copyright 2022 schukai GmbH. All rights reserved.
+## Use of this source code is governed by a AGPL-3.0
+## license that can be found in the LICENSE file.
+
 PROJECT_ROOT:=$(dir $(realpath $(lastword $(MAKEFILE_LIST))))
 THIS_MAKEFILE:=$(word $(words $(MAKEFILE_LIST)),$(MAKEFILE_LIST))
 THIS_MAKEFILE_PATH:=$(PROJECT_ROOT)$(THIS_MAKEFILE) 
@@ -137,5 +141,16 @@ endif
 fetch-licenses:
 	go-licenses save $(GO_CURRENT_MODULE) --ignore gitlab.schukai.com --force --save_path $(PROJECT_ROOT)licenses/ ; cd -
 
+# https://spdx.github.io/spdx-spec/v2.3/SPDX-license-list/
+ADDLICENSE_BIN ?= addlicense
+ifeq ($(shell command -v $(ADDLICENSE_BIN) 2> /dev/null),)
+	$(shell go install github.com/google/addlicense@latest)
+	EXECUTABLES = $(EXECUTABLES:-) $(ADDLICENSE_BIN);
+endif
+
+.PHONY: add-licenses
+## Add license headers to all go files
+add-licenses:
+	addlicense -c "schukai GmbH" -s -l "AGPL-3.0-or-later" ./*.go
 
 
diff --git a/api.go b/api.go
index 86cdfb132fd0e025de5cd2b630184e47f1abc605..b8e79fd899d01982a805be60751c9f5ea4fbafa1 100644
--- a/api.go
+++ b/api.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import "github.com/imdario/mergo"
diff --git a/api_test.go b/api_test.go
index 9a0c4eec870313168a87fa1e2e3d4cab7de9bdc7..4bce996938dc64ffffcb29459da8327855c0fb47 100644
--- a/api_test.go
+++ b/api_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/benchmark_test.go b/benchmark_test.go
index 9e55e52856f1115dff2d9807b9d8179776a319d0..094f9d704ee337b0f15ce10ccbf288c8498c9e67 100644
--- a/benchmark_test.go
+++ b/benchmark_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/change.go b/change.go
index d68aad6e6ffde8bd41dab5b8b213717ec873202c..d031649b1c0d12e288e46a0d146f24a1554bba86 100644
--- a/change.go
+++ b/change.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/change_test.go b/change_test.go
index 7e1b6616ecc7f7b931cf4ebe16f95e0e07656a03..0d4e8e7dc07535c5838fefb5c7a790e46a10604c 100644
--- a/change_test.go
+++ b/change_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/constants.go b/constants.go
index eb3eaffb457fdf428ca6bdc7fa9974574b24deb0..8506736c024095182882eb941dbd634f6346a889 100644
--- a/constants.go
+++ b/constants.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 const fileName = "config"
diff --git a/env.go b/env.go
index 871e4fe05a4d61784c84cc4f4816a06838d7bdd7..87dd684153fababd306da4103db1ac9aae4e13d4 100644
--- a/env.go
+++ b/env.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/env_test.go b/env_test.go
index 7847f142fbb366531c4a7371f775b55e0b012adb..9dbf42dc31036e7bf415371d4b992b676288bb99 100644
--- a/env_test.go
+++ b/env_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/error.go b/error.go
index 0addae37b10d3ed7658d4b08a8a7c90392def8d2..a02a0d61928b12f6249a9c2d58612349a8373cbf 100644
--- a/error.go
+++ b/error.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/error_test.go b/error_test.go
index e6c022bb2b183f43efc0b3d8944576b00bf5cbc0..4ba827a5535e607ad1400240b5d9f366aae195d9 100644
--- a/error_test.go
+++ b/error_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/export.go b/export.go
index 269817ba2eb6a1acf35d211e6619cb3194c78b79..82ed43dac7247b8f0fd9e512ce5e3f2747d05329 100644
--- a/export.go
+++ b/export.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/export_test.go b/export_test.go
index 8d87c1336b0d858a5c8fa8c9afbd93dcc06d5abd..2133e867bd48d6a776a2fdd319e8d4dee9c8c3f2 100644
--- a/export_test.go
+++ b/export_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/file.go b/file.go
index 8685fd2d7682028837862cc11c4d25f71de21514..3870c9c8158aa6699b8f23a62e265dfe5ebe0580 100644
--- a/file.go
+++ b/file.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/file_test.go b/file_test.go
index 677d43ebd50269b0f1f083c147b0a217ef6dd03f..4b05aa290e63efef2e7a8fa7b1fe2bd1bf8a6e88 100644
--- a/file_test.go
+++ b/file_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/filesystem.go b/filesystem.go
index 8e8d4cb53310e55d065cc35504a37678c5483758..302bff44d581327953fdfc7db3a6bf24200aebde 100644
--- a/filesystem.go
+++ b/filesystem.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/filesystem_test.go b/filesystem_test.go
index f0a061cde2a657554d244d20afbcc4cd0fadc1be..a236696a65895dc608886978d2f0c1aa665b163c 100644
--- a/filesystem_test.go
+++ b/filesystem_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import "testing"
diff --git a/flags.go b/flags.go
index c9d75b849583f69b67a42cf139504e0bd7ec5874..44dcfb74c2a25f05092c49162391902c67141433 100644
--- a/flags.go
+++ b/flags.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/flags_test.go b/flags_test.go
index 435bd790686c208e1582eb884bcfc9d03bbab5d8..195180c3d45f8adbbf80799d553fa9a9954cbcb5 100644
--- a/flags_test.go
+++ b/flags_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/format.go b/format.go
index b7f10a43e7cc2841488ec6a953102f8c7a417fb4..e3f3e317bb8049b23af8c6169608ac4a9afa45ff 100644
--- a/format.go
+++ b/format.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 type Format int
diff --git a/format_test.go b/format_test.go
index aa2a876abf187ea99e499f2dcad6d3e9305cbcd2..a14897bb7c424d88cb05a3b4d18f0ee23cc2846d 100644
--- a/format_test.go
+++ b/format_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import "testing"
diff --git a/http-handler.go b/http-handler.go
index c8f9bd10c7e01e55d4d7726f169aab9bc2af3457..058846ca8180ebae40c7d5363f06c0e62df83bf8 100644
--- a/http-handler.go
+++ b/http-handler.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/http-handler_test.go b/http-handler_test.go
index 9e65107326dc431fd72d630673ab7c6666eb4670..2f84e6fa3026ccf4dd9a237b39bed06fde0c5000 100644
--- a/http-handler_test.go
+++ b/http-handler_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/import.go b/import.go
index 82238ed1bbcc47a9f31a5cfed833a118650f09b2..687869a78cbf76b306263fd5d3231b13f4905812 100644
--- a/import.go
+++ b/import.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/import_test.go b/import_test.go
index f908f49aad55dcd27383b9954919921727f02013..9502c3608c0ed83ec41df062f4fb530dc5b6c3cd 100644
--- a/import_test.go
+++ b/import_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/integration_test.go b/integration_test.go
index 60ff24a393a090539d17904509c2e5163c2a77f6..0f0337df3c909fb5acd1593bc167f30c72afcb32 100644
--- a/integration_test.go
+++ b/integration_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/properties.go b/properties.go
index 0acc5db983b58c896553f94f7888602527c3583e..bc783eeec32c23008b004dfbbee9c660a7294940 100644
--- a/properties.go
+++ b/properties.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/properties_test.go b/properties_test.go
index 499b04faac55c586d079629f436b82264260ad96..b6dbc8b0a0461184d7cca35f2ac7486057676939 100644
--- a/properties_test.go
+++ b/properties_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/settings.go b/settings.go
index 1828db4e70bffd7cb64281ef216fbc33a498a896..dfbbce088f8e4e8dbc8cba3af9305e6ed5352d18 100644
--- a/settings.go
+++ b/settings.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/settings_test.go b/settings_test.go
index b7e1387ad8787e5612250f3b39aba0c51e9a3344..c0326e44ca190bf3f45dc74eabc3697a682c1b38 100644
--- a/settings_test.go
+++ b/settings_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 type ConfigStruct1 struct {
diff --git a/stream.go b/stream.go
index 035796b62afd84736bca1b267d9345ac2eb7d314..4c3f77ccd73b7c6705a3779767f19ffa4e9c115b 100644
--- a/stream.go
+++ b/stream.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import "io"
diff --git a/stream_test.go b/stream_test.go
index 991403341f5f081d486bfe398b484f1bdd57976a..44db5df6633426450a58dfcdba684e354875554b 100644
--- a/stream_test.go
+++ b/stream_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/tags.go b/tags.go
index c3b964a2ae6d93f280f21396801ff155c0524bb7..3142e903d1c9412581ca628ae5def36a9c48fa17 100644
--- a/tags.go
+++ b/tags.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/tags_test.go b/tags_test.go
index 256fd7757681103228dd03b21df06df2df02a464..d21da608e7b5bb1f3bc76e778798a92ad1274931 100644
--- a/tags_test.go
+++ b/tags_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/watch.go b/watch.go
index 818c03b2d9696d02cad2756bf41f6aacc9f19f05..3d7ad7e5cafbe68a269496f59982de07a91e37ab 100644
--- a/watch.go
+++ b/watch.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (
diff --git a/watch_test.go b/watch_test.go
index ea0b06f2ca2afb956837a061f5b0d3dfb3c88c01..76aa31031e73234d2da47620d3a5bda23380bbdc 100644
--- a/watch_test.go
+++ b/watch_test.go
@@ -1,3 +1,6 @@
+// Copyright 2022 schukai GmbH
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
 package configuration
 
 import (