diff --git a/Dockerfile b/Dockerfile
index ab6dd3b..f6773a9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -13,7 +13,7 @@ RUN set -ex; \
 
 # add a non-root user to run our code as
 RUN adduser --disabled-password --gecos "" appuser
-RUN mkdir -p /home/appuser/.cache/node/corepack/v1
+RUN mkdir -p /home/appuser/.cache/node/corepack
 
 # install our test runner to /opt
 WORKDIR /opt/test-runner
@@ -22,7 +22,9 @@ COPY . .
 # Build the test runner
 RUN set -ex; \
   corepack enable; \
+  # install corepack globally with the last known good version of yarn
   corepack pack -o ./corepack.tgz; \
+  COREPACK_ENABLE_NETWORK=0 corepack install -g "./corepack.tgz"; \
   # install all the development modules (used for building)
   yarn cache clean; \
   yarn install; \
@@ -36,5 +38,8 @@ RUN set -ex; \
   #
   # TODO: yarn workspaces focus --production;
 
+ENV COREPACK_ENABLE_NETWORK=0
+ENV YARN_ENABLE_OFFLINE_MODE=1
+
 USER appuser
 ENTRYPOINT [ "/opt/test-runner/bin/run.sh" ]
diff --git a/bin/run.sh b/bin/run.sh
index 3c19bdd..2ebb746 100755
--- a/bin/run.sh
+++ b/bin/run.sh
@@ -172,8 +172,6 @@ result_file="${OUTPUT}results.json"
 # Check yarn
 if test -f "$ROOT/corepack.tgz"; then
   YARN_ENABLE_OFFLINE_MODE=1 yarn -v
-  COREPACK_ENABLE_NETWORK=0 corepack enable
-  YARN_ENABLE_OFFLINE_MODE=1 yarn -v
 
   # COREPACK_ENABLE_NETWORK=0 corepack install -g "$ROOT/corepack.tgz"
 else