diff --git a/LICENSE b/LICENSE
index 172596d..62b027f 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,7 @@
 MIT License
 
 Copyright (c) 2017-2022 yuk7
+Copyright (c) 2024 TKTek
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index d1f40ae..731986a 100644
--- a/README.md
+++ b/README.md
@@ -94,3 +94,4 @@ $ make ARCH=arm64 OUT_ZIP=Alpine_arm64.zip
 |  DLR  |  file downloader  | curl |
 |  DLR_FLAGS  |  downloader flags  | -L |
 |  BASE_URL  |  base rootfs url  | https:~ |
+|  ROOTFS_TARBALL_CKSM_URL  |  sha-sum for the base rootfs tarball  |  https:~ |
diff --git a/src_arm64/Makefile b/src_arm64/Makefile
index b533303..8df4897 100644
--- a/src_arm64/Makefile
+++ b/src_arm64/Makefile
@@ -3,7 +3,8 @@ LNCR_EXE=Alpine.exe
 
 DLR=curl
 DLR_FLAGS=-L
-BASE_URL=https://dl-cdn.alpinelinux.org/alpine/v3.18/releases/aarch64/alpine-minirootfs-3.18.4-aarch64.tar.gz
+BASE_URL=https://dl-cdn.alpinelinux.org/alpine/v3.20/releases/aarch64/alpine-minirootfs-3.20.3-aarch64.tar.gz
+ROOTFS_TARBALL_CKSM_URL=${BASE_URL}.sha512
 LNCR_ZIP_URL=https://github.com/yuk7/wsldl/releases/download/23072600/icons_arm64.zip
 LNCR_ZIP_EXE=Alpine.exe
 
@@ -48,6 +49,12 @@ rootfs: base.tar.gz profile
 base.tar.gz:
 	@echo -e '\e[1;31mDownloading base.tar.gz...\e[m'
 	$(DLR) $(DLR_FLAGS) $(BASE_URL) -o base.tar.gz
+	$(DLR) $(DLR_FLAGS) $(ROOTFS_TARBALL_CKSM_URL) -o base.tar.gz.sha512sum.txt
+	if ! (head -c 128 < base.tar.gz.sha512sum.txt; echo "  base.tar.gz") | shasum -c; then \
+		echo 'Checksum failed.'; \
+		rm base.tar.gz base.tar.gz.sha512sum.txt; \
+		exit 1; \
+	fi
 
 clean:
 	@echo -e '\e[1;31mCleaning files...\e[m'
@@ -56,5 +63,6 @@ clean:
 	-rm Launcher.exe
 	-rm icons.zip
 	-rm rootfs.tar.gz
+	-rm rootfs.tar.gz.sha512sum.txt
 	-sudo rm -r rootfs
 	-rm base.tar.gz
diff --git a/src_x64/Makefile b/src_x64/Makefile
index b5d5ade..ead99a0 100644
--- a/src_x64/Makefile
+++ b/src_x64/Makefile
@@ -3,7 +3,8 @@ LNCR_EXE=Alpine.exe
 
 DLR=curl
 DLR_FLAGS=-L
-BASE_URL=https://dl-cdn.alpinelinux.org/alpine/v3.18/releases/x86_64/alpine-minirootfs-3.18.4-x86_64.tar.gz
+BASE_URL=https://dl-cdn.alpinelinux.org/alpine/v3.20/releases/x86_64/alpine-minirootfs-3.20.3-x86_64.tar.gz
+ROOTFS_TARBALL_CKSM_URL=${BASE_URL}.sha512
 LNCR_ZIP_URL=https://github.com/yuk7/wsldl/releases/download/23072600/icons.zip
 LNCR_ZIP_EXE=Alpine.exe
 
@@ -50,6 +51,12 @@ rootfs: base.tar.gz profile
 base.tar.gz:
 	@echo -e '\e[1;31mDownloading base.tar.gz...\e[m'
 	$(DLR) $(DLR_FLAGS) $(BASE_URL) -o base.tar.gz
+	$(DLR) $(DLR_FLAGS) $(ROOTFS_TARBALL_CKSM_URL) -o base.tar.gz.sha512sum.txt
+	if ! (head -c 128 < base.tar.gz.sha512sum.txt; echo "  base.tar.gz") | shasum -c; then \
+		echo 'Checksum failed.'; \
+		rm base.tar.gz base.tar.gz.sha512sum.txt; \
+		exit 1; \
+	fi
 
 clean:
 	@echo -e '\e[1;31mCleaning files...\e[m'
@@ -58,5 +65,6 @@ clean:
 	-rm Launcher.exe
 	-rm icons.zip
 	-rm rootfs.tar.gz
+	-rm rootfs.tar.gz.sha512sum.txt
 	-sudo rm -r rootfs
 	-rm base.tar.gz