diff --git a/tests/abi/config/config.hpp b/tests/abi/config/config.hpp
index d52228bb1..a824625f6 100644
--- a/tests/abi/config/config.hpp
+++ b/tests/abi/config/config.hpp
@@ -1,3 +1,11 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  JSON for Modern C++ (supporting code)
+// |  |  |__   |  |  | | | |  version 3.11.1
+// |_____|_____|_____|_|___|  https://github.com/nlohmann/json
+//
+// SPDX-FileCopyrightText: 2013-2022 Niels Lohmann <https://nlohmann.me>
+// SPDX-License-Identifier: MIT
+
 #pragma once
 
 #include "doctest.h"
diff --git a/tests/abi/config/custom.cpp b/tests/abi/config/custom.cpp
index 98c3a9996..9567e6c51 100644
--- a/tests/abi/config/custom.cpp
+++ b/tests/abi/config/custom.cpp
@@ -1,3 +1,11 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  JSON for Modern C++ (supporting code)
+// |  |  |__   |  |  | | | |  version 3.11.1
+// |_____|_____|_____|_|___|  https://github.com/nlohmann/json
+//
+// SPDX-FileCopyrightText: 2013-2022 Niels Lohmann <https://nlohmann.me>
+// SPDX-License-Identifier: MIT
+
 #include "doctest_compatibility.h"
 
 #include "config.hpp"
diff --git a/tests/abi/config/default.cpp b/tests/abi/config/default.cpp
index e50be7dcb..0562db73b 100644
--- a/tests/abi/config/default.cpp
+++ b/tests/abi/config/default.cpp
@@ -1,3 +1,11 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  JSON for Modern C++ (supporting code)
+// |  |  |__   |  |  | | | |  version 3.11.1
+// |_____|_____|_____|_|___|  https://github.com/nlohmann/json
+//
+// SPDX-FileCopyrightText: 2013-2022 Niels Lohmann <https://nlohmann.me>
+// SPDX-License-Identifier: MIT
+
 #include "doctest_compatibility.h"
 
 #include "config.hpp"
diff --git a/tests/abi/config/noversion.cpp b/tests/abi/config/noversion.cpp
index f8d8972e3..f8a5530bf 100644
--- a/tests/abi/config/noversion.cpp
+++ b/tests/abi/config/noversion.cpp
@@ -1,3 +1,11 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  JSON for Modern C++ (supporting code)
+// |  |  |__   |  |  | | | |  version 3.11.1
+// |_____|_____|_____|_|___|  https://github.com/nlohmann/json
+//
+// SPDX-FileCopyrightText: 2013-2022 Niels Lohmann <https://nlohmann.me>
+// SPDX-License-Identifier: MIT
+
 #include "doctest_compatibility.h"
 
 #include "config.hpp"