diff --git a/images/Dockerfile.bottlecap.compile b/images/Dockerfile.bottlecap.compile
index 877e6e21e..b01b0913f 100644
--- a/images/Dockerfile.bottlecap.compile
+++ b/images/Dockerfile.bottlecap.compile
@@ -5,7 +5,9 @@ ARG FIPS
 ARG DEBUG
 
 # Install dependencies
-RUN --mount=type=cache,target=/var/cache/yum \
+# sharing=private gives each concurrent build its own yum cache; on a shared
+# cache, concurrent builds fail here with corrupted repodata and missing rpms
+RUN --mount=type=cache,sharing=private,target=/var/cache/yum \
     yum install -y clang cmake3 compiler-rt curl go make perl unzip
 
 # Install Protocol Buffers compiler by hand, since AL2 does not have a recent enough version.