diff --git a/Makefile b/Makefile
index e75cc8f..2d9cd66 100644
--- a/Makefile
+++ b/Makefile
@@ -4,13 +4,7 @@ include config.mk
 # VARIABLES #
 #############
 
-CPU_ARCH := $(if $(shell which arch 2>/dev/null),\
-	$(shell arch),\
-	$(shell lscpu | grep ^Architecture: | sed "s/^Architecture:[[:space:]]*\([[:alnum:][:punct:]]\+\).*/\1/"))
 HOSTNAME := $(shell cat /etc/hostname)
-IMAGE_PREFIX := $(if $(filter armv7%,$(CPU_ARCH)),armv7/)
-REGISTRY_DOMAIN := git.joeac.net
-REGISTRY_USER := joeac
 MODULES_pi-broughton := http gemini smtp vaultwarden ln
 MODULES_blade-canongate := etherpad
 MASTER_NODE := pi-broughton
@@ -31,7 +25,6 @@ RESTART_NGINX := sudo rc-service nginx restart
 # FUNCTIONS #
 #############
 
-container_image_name = $(REGISTRY_DOMAIN)/$(REGISTRY_USER)/joeac.net-$(module)
 dyndns_module_target = $(if $(SUBDOMAIN_$(module)),/etc/periodic/daily/dyndns-$(SUBDOMAIN_$(module)).joeac.net)
 openrc_module_target = $(if $(filter $(COMPOSE_SERVICES),$(module)),~/.config/rc/init.d/joeac.net.$(module))
 install_submake_file = $(shell [ -f "$(module)/install.mk" ] && echo "$(module)/install.mk")
diff --git a/compose.yml b/compose.yml
index 1aac108..8a8c6fe 100644
--- a/compose.yml
+++ b/compose.yml
@@ -1,6 +1,6 @@
 services:
   gemini:
-    image: git.joeac.net/joeac/${CONTAINER_PREFIX}joeac.net-gemini
+    image: git.joeac.net/joeac/${IMAGE_PREFIX}joeac.net-gemini
     container_name: joeac.net-gemini
     build:
       context: .
@@ -9,7 +9,7 @@ services:
       - "${GEMINI_PORT}:1965"
 
   http:
-    image: git.joeac.net/joeac/${CONTAINER_PREFIX}joeac.net-http
+    image: git.joeac.net/joeac/${IMAGE_PREFIX}joeac.net-http
     container_name: joeac.net-http
     build:
       context: .
@@ -30,7 +30,7 @@ services:
       - "${HTTP_PORT}:80"
 
   etherpad:
-    image: git.joeac.net/joeac/${CONTAINER_PREFIX}joeac.net-etherpad
+    image: git.joeac.net/joeac/${IMAGE_PREFIX}joeac.net-etherpad
     container_name: joeac.net-etherpad
     build:
       context: .
@@ -48,7 +48,7 @@ services:
       - "${ETHERPAD_PORT}:9001"
 
   smtp:
-    image: git.joeac.net/joeac/${CONTAINER_PREFIX}joeac.net-smtp
+    image: git.joeac.net/joeac/${IMAGE_PREFIX}joeac.net-smtp
     container_name: joeac.net-smtp
     build:
       context: .
diff --git a/container.mk b/container.mk
index 3b1e5ae..101e4e4 100644
--- a/container.mk
+++ b/container.mk
@@ -1,7 +1,16 @@
+CPU_ARCH := $(if $(shell which arch 2>/dev/null),\
+	$(shell arch),\
+	$(shell lscpu | grep ^Architecture: | sed "s/^Architecture:[[:space:]]*\([[:alnum:][:punct:]]\+\).*/\1/"))
+IMAGE_PREFIX := $(if $(filter armv7%,$(CPU_ARCH)),armv7/)
+REGISTRY_DOMAIN := git.joeac.net
+REGISTRY_USER := joeac
+
+container_image_name = $(REGISTRY_DOMAIN)/$(REGISTRY_USER)/$(CONTAINER_PREFIX)joeac.net-$(module)
+
 define build_module_rule =
 .PHONY: build_$(module)
 build_$(module): make_$(module) $(module).Dockerfile
-	podman-compose build $(module)
+	IMAGE_PREFIX="$(IMAGE_PREFIX)" podman-compose build $(module)
 endef
 
 define push_module_rule =