diff --git a/Dockerfile.dapper b/Dockerfile.dapper
index c18d1b45..52f9f459 100644
--- a/Dockerfile.dapper
+++ b/Dockerfile.dapper
@@ -1,4 +1,5 @@
 FROM ubuntu:18.04
+ENV ImageOS=ubuntu20
 RUN apt-get update && apt-get install -y g++ git cmake libgtk-3-dev \ 
     libglvnd-dev libglu1-mesa-dev freeglut3-dev libasound2-dev
 WORKDIR ${DAPPER_SOURCE:-/source}
diff --git a/build/android/Dockerfile b/build/android/Dockerfile
index 0f435414..85b0d5cd 100644
--- a/build/android/Dockerfile
+++ b/build/android/Dockerfile
@@ -1,4 +1,5 @@
 FROM mingc/android-build-box
+ENV ImageOS=ubuntu20
 RUN apt-get update
 RUN apt-get remove git -y
 RUN apt-get install software-properties-common -y
diff --git a/build/baremetalpi/Dockerfile b/build/baremetalpi/Dockerfile
index f4186da5..6361b7a8 100644
--- a/build/baremetalpi/Dockerfile
+++ b/build/baremetalpi/Dockerfile
@@ -1,4 +1,5 @@
 FROM ubuntu:18.04
+ENV ImageOS=ubuntu20
 RUN apt-get update
 RUN apt-get install software-properties-common -y
 RUN add-apt-repository ppa:git-core/ppa -y
diff --git a/build/n3ds/Dockerfile b/build/n3ds/Dockerfile
index c4e85995..fb38953d 100644
--- a/build/n3ds/Dockerfile
+++ b/build/n3ds/Dockerfile
@@ -1,4 +1,5 @@
 FROM ubuntu:18.04
+ENV ImageOS=ubuntu20
 RUN apt-get update
 RUN apt-get install software-properties-common -y
 RUN add-apt-repository ppa:git-core/ppa -y
diff --git a/build/rpi/Dockerfile b/build/rpi/Dockerfile
index 3073f452..c8195bc8 100644
--- a/build/rpi/Dockerfile
+++ b/build/rpi/Dockerfile
@@ -1,4 +1,5 @@
 FROM ubuntu:18.04
+ENV ImageOS=ubuntu20
 RUN apt-get update
 RUN apt-get install software-properties-common -y
 RUN add-apt-repository ppa:git-core/ppa -y