diff --git a/shell/debian.sh b/shell/debian.sh
index 4ce02de..e4085df 100644
--- a/shell/debian.sh
+++ b/shell/debian.sh
@@ -32,6 +32,19 @@ apt_install_target() {
 	done
 }
 
+apt_sources_write() {
+	printf "%s" "\
+deb https://deb.debian.org/debian \
+${DEBIAN_CODENAME} main non-free-firmware contrib non-free
+deb https://deb.debian.org/debian \
+${DEBIAN_CODENAME}-backports main non-free-firmware contrib non-free
+deb https://deb.debian.org/debian \
+${DEBIAN_CODENAME}-updates main non-free-firmware contrib non-free
+deb https://deb.debian.org/debian-security \
+${DEBIAN_CODENAME}-security main non-free-firmware contrib non-free
+" >"/etc/apt/sources.list"
+}
+
 apt_update() {
 	apt-get \
 		update
diff --git a/shell/rescue/common.sh b/shell/rescue/common.sh
index 3671d15..306f7fa 100644
--- a/shell/rescue/common.sh
+++ b/shell/rescue/common.sh
@@ -13,16 +13,7 @@ Dir::Etc::SourceParts \"\";
 Dpkg::Progress True;
 " >"/etc/apt/apt.conf.d/apt.conf"
 	# apt / sources
-	printf "%s" "\
-deb https://deb.debian.org/debian \
-${DEBIAN_CODENAME} main non-free-firmware contrib non-free
-deb https://deb.debian.org/debian \
-${DEBIAN_CODENAME}-backports main non-free-firmware contrib non-free
-deb https://deb.debian.org/debian \
-${DEBIAN_CODENAME}-updates main non-free-firmware contrib non-free
-deb https://deb.debian.org/debian-security \
-${DEBIAN_CODENAME}-security main non-free-firmware contrib non-free
-" >"/etc/apt/sources.list"
+	apt_sources_write
 	# bash / rc
 	main_link_bashrc
 	mv .bashrc .bashrc.old