diff --git a/Dockerfile b/Dockerfile
index cf8948d..aabba03 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -11,7 +11,7 @@ RUN \
   iris session $ISC_PACKAGE_INSTANCENAME -U %SYS < /tmp/iris.script && \
   iris stop $ISC_PACKAGE_INSTANCENAME quietly
 
-FROM --platform=$TARGETPLATFORM intersystems/iris-community:2024.1-linux-${BUILDARCH}
+FROM --platform=$TARGETPLATFORM intersystems/iris-community:2024.1-linux-${TARGETARCH}
 
 USER root
 
diff --git a/Dockerfile-amd64 b/Dockerfile-amd64
index b9fcd7d..d3ae80e 100644
--- a/Dockerfile-amd64
+++ b/Dockerfile-amd64
@@ -1,4 +1,5 @@
 # syntax = edrevo/dockerfile-plus
+ARG IMAGE=containers.intersystems.com/intersystems/iris-community:latest-cd
 
 INCLUDE+ Dockerfile-phase1
 
diff --git a/Dockerfile-arm64 b/Dockerfile-arm64
index 495cb9c..7ace770 100644
--- a/Dockerfile-arm64
+++ b/Dockerfile-arm64
@@ -1,4 +1,5 @@
 # syntax = edrevo/dockerfile-plus
+ARG IMAGEARM=containers.intersystems.com/intersystems/iris-community:latest-cd
 
 INCLUDE+ Dockerfile-phase1
 
diff --git a/Dockerfile-phase1 b/Dockerfile-phase1
index 44944ce..2c4eae9 100644
--- a/Dockerfile-phase1
+++ b/Dockerfile-phase1
@@ -1,6 +1,6 @@
 ARG IMAGE=intersystems/iris-community:latest-cd
 ARG DEV=0
-FROM $IMAGE
+FROM --platform=${BUILDPLATFORM} $IMAGE
 
 ARG IPM_INSTALLER=https://pm.community.intersystems.com/packages/zpm/latest/installer