diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 1764e82a..6cd74c8e 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -43,13 +43,6 @@ jobs:
     - name: Print GITHUB_WORKSPACE contents
       run: ls -la ${GITHUB_WORKSPACE}
 
-    # Use a modified Dockerfile which builds off a partially built base image
-    # to leverage an existing Cargo cache and thus speed up deployment.
-    - name: Install modified Dockerfile into Krill checkout
-      run: |
-        set -x
-        cp ${GITHUB_WORKSPACE}/rpki-deploy/terraform/krill-e2e-test/lib/docker/krill/Dockerfile ${GITHUB_WORKSPACE}/krill/Dockerfile
-
     - name: Install Python 3 venv package
       run: |
         set -x
diff --git a/Dockerfile b/Dockerfile
index 6641b360..9647e2cb 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,8 +1,14 @@
 #
-# -- stage 1: build krill and krillc
+# Make the base image configurable so that the E2E test can use a base image
+# with a prepopulated Cargo build cache to accelerate the build process.
 # Use Ubuntu 16.04 because this is what the Travis CI Krill build uses.
 #
-FROM ubuntu:16.04 AS builder
+ARG BASE_IMG=ubuntu:16.04
+
+#
+# -- stage 1: build krill and krillc
+#
+FROM ${BASE_IMG} AS builder
 
 # Install Rust
 RUN apt-get update && apt-get install -y --no-install-recommends \