diff --git a/.buildkite/pipeline.yaml b/.buildkite/pipeline.yaml
index ad4567182..0e3157c85 100644
--- a/.buildkite/pipeline.yaml
+++ b/.buildkite/pipeline.yaml
@@ -38,6 +38,9 @@ _templates:
         ./pkg/tcpip/transport/tcp
         ./pkg/tcpip/transport/udp
         ./pkg/waiter
+env:
+  # Force a clean checkout every time to avoid reuse of files between runs.
+  BUILDKITE_CLEAN_CHECKOUT: true
 
 steps:
   # Run basic smoke tests before preceding to other tests.
diff --git a/.buildkite/release.yaml b/.buildkite/release.yaml
index 2221fd915..e44b20001 100644
--- a/.buildkite/release.yaml
+++ b/.buildkite/release.yaml
@@ -10,6 +10,10 @@ _templates:
         - exit_status: "*"
           limit: 2
 
+env:
+  # Force a clean checkout every time to avoid reuse of files between runs.
+  BUILDKITE_CLEAN_CHECKOUT: true
+
 steps:
   - <<: *common
     label: ":ship: Push all images (x86_64)"