diff --git a/tests/docker/Dockerfile.composer b/tests/docker/Dockerfile.composer
index 13c4708ce..97b6557e2 100644
--- a/tests/docker/Dockerfile.composer
+++ b/tests/docker/Dockerfile.composer
@@ -23,9 +23,9 @@ RUN apt-get update \
 
 RUN set -eu \
  && cd /tmp \
- && curl -fsSL --retry 3 -o composer.phar \
+ && curl -fsSL --retry 3 --retry-all-errors -o composer.phar \
       "https://getcomposer.org/download/${COMPOSER_VERSION}/composer.phar" \
- && curl -fsSL --retry 3 -o composer.phar.sha256sum \
+ && curl -fsSL --retry 3 --retry-all-errors -o composer.phar.sha256sum \
       "https://getcomposer.org/download/${COMPOSER_VERSION}/composer.phar.sha256sum" \
  && echo "$(cut -d' ' -f1 composer.phar.sha256sum)  composer.phar" | sha256sum -c - \
  && if [ -n "${COMPOSER_SHA256}" ]; then \
diff --git a/tests/docker/Dockerfile.sbt b/tests/docker/Dockerfile.sbt
index 40010f4bf..247a5f16e 100644
--- a/tests/docker/Dockerfile.sbt
+++ b/tests/docker/Dockerfile.sbt
@@ -41,9 +41,12 @@ ARG SCALA_CLI_VERSION=1.17.1
 ARG SCALA_CLI_SHA256_AMD64=4186bfac6552097fbfd3939bdf2ecdec1cb55baafcbf6259bef5c04e08858eb3
 ARG SCALA_CLI_SHA256_ARM64=a12ed53f4723f3e9312a2383e47664b4beaccf2be366cff40adf6b054426156f
 
+# --retry-all-errors: plain --retry skips most HTTP errors, so one bad
+# response from the GitHub release-asset CDN (curl exit 22) failed the
+# image build and evicted a merge-queue entry (run 37894279963).
 RUN set -eu \
  && cd /tmp \
- && curl -fsSL --retry 3 -o sbt.tgz \
+ && curl -fsSL --retry 3 --retry-all-errors -o sbt.tgz \
       "https://github.com/sbt/sbt/releases/download/v${SBT_LAUNCHER_VERSION}/sbt-${SBT_LAUNCHER_VERSION}.tgz" \
  && echo "${SBT_LAUNCHER_SHA256}  sbt.tgz" | sha256sum -c - \
  && tar -C /opt -xzf sbt.tgz \
@@ -53,15 +56,15 @@ RUN set -eu \
 # One launcher script per Mill line, installed as mill-<version>.
 RUN set -eu \
  && cd /tmp \
- && curl -fsSL --retry 3 -o mill-011 \
+ && curl -fsSL --retry 3 --retry-all-errors -o mill-011 \
       "https://github.com/com-lihaoyi/mill/releases/download/${MILL_011_VERSION}/${MILL_011_VERSION}" \
  && echo "${MILL_011_SHA256}  mill-011" | sha256sum -c - \
  && install -m 0755 mill-011 "/usr/local/bin/mill-${MILL_011_VERSION}" \
- && curl -fsSL --retry 3 -o mill-012 \
+ && curl -fsSL --retry 3 --retry-all-errors -o mill-012 \
       "https://repo1.maven.org/maven2/com/lihaoyi/mill-dist/${MILL_012_VERSION}/mill-dist-${MILL_012_VERSION}-mill.sh" \
  && echo "${MILL_012_SHA256}  mill-012" | sha256sum -c - \
  && install -m 0755 mill-012 "/usr/local/bin/mill-${MILL_012_VERSION}" \
- && curl -fsSL --retry 3 -o mill-1 \
+ && curl -fsSL --retry 3 --retry-all-errors -o mill-1 \
       "https://repo1.maven.org/maven2/com/lihaoyi/mill-dist/${MILL_1_VERSION}/mill-dist-${MILL_1_VERSION}-mill.sh" \
  && echo "${MILL_1_SHA256}  mill-1" | sha256sum -c - \
  && install -m 0755 mill-1 "/usr/local/bin/mill-${MILL_1_VERSION}" \
@@ -74,7 +77,7 @@ RUN set -eu \
       arm64) arch=aarch64; sum="${SCALA_CLI_SHA256_ARM64}";; \
       *) echo "unsupported architecture" >&2; exit 1;; \
     esac \
- && curl -fsSL --retry 3 -o scala-cli.gz \
+ && curl -fsSL --retry 3 --retry-all-errors -o scala-cli.gz \
       "https://github.com/VirtusLab/scala-cli/releases/download/v${SCALA_CLI_VERSION}/scala-cli-${arch}-pc-linux.gz" \
  && echo "${sum}  scala-cli.gz" | sha256sum -c - \
  && gunzip scala-cli.gz \