1 files changed, 3 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index 5e4d9f4..b452eb2 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: AGPL-3.0-only
+# SPDX-FileContributor: Runxi Yu <https://runxiyu.org>
+
 .PHONY: clean version.go
 
 CFLAGS = -Wall -Wextra -Werror -pedantic -std=c99 -D_GNU_SOURCE