diff --git a/.gitignore b/.gitignore
index f9a1f743d..6bc0e2a1a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -29,6 +29,9 @@ test_results/
 *.profraw
 coverage-reports/
 
+# The integration tests' default scratch root.
+.test-scratch/
+
 # API docs for local preview only.
 _site/
 _serve/
diff --git a/Makefile b/Makefile
index 1855256d2..7f4ca4445 100644
--- a/Makefile
+++ b/Makefile
@@ -278,6 +278,11 @@ PRESERVE_KERNELS ?= false
 # Override with SCRATCH_ROOT=/your/path on the command line.
 SCRATCH_ROOT ?= $(ROOT_DIR)/.test-scratch
 
+# An editable build's images exist in no registry: init-block builds the
+# init image before the data directory is cleared here, and a locally built
+# builder image is in the same position. The recipe lands the tars from bin/
+# after its own system start, into the store the tests actually see; absent
+# a tar, the runtime pulls its documented default instead.
 define RUN_INTEGRATION
 	@echo Ensuring apiserver stopped before the CLI integration tests...
 	@bin/container system stop && sleep 3 && scripts/ensure-container-stopped.sh
@@ -298,6 +303,14 @@ define RUN_INTEGRATION
 		CLITEST_LOG_ROOT=$(LOG_ROOT) && export CLITEST_LOG_ROOT ; \
 		CLITEST_SCRATCH_ROOT=$(SCRATCH_ROOT) && export CLITEST_SCRATCH_ROOT ; \
 		CONTAINER_CLI_PATH=$(ROOT_DIR)/bin/container && export CONTAINER_CLI_PATH ; \
+		if [ -f bin/init.tar ]; then \
+			echo "==> Loading the built init image" && \
+			bin/container i load -i bin/init.tar ; \
+		fi && \
+		if [ -f bin/builder.tar ]; then \
+			echo "==> Loading the built builder image" && \
+			bin/container i load -i bin/builder.tar ; \
+		fi && \
 		echo "==> Starting warmup tests" && \
 		$(SWIFT) test $(INTEGRATION_SWIFT_EXTRA) -c $(BUILD_CONFIGURATION) $(SWIFT_CONFIGURATION) --filter "$(WARMUP_FILTER)" && \
 		echo "==> Starting $(words $(CONCURRENT_TEST_SUITES)) test suites concurrently (width=$(PARALLEL_WIDTH))" && \
diff --git a/Sources/ContainerTestSupport/WarmupImage.swift b/Sources/ContainerTestSupport/WarmupImage.swift
index f839525cd..f379fbec4 100644
--- a/Sources/ContainerTestSupport/WarmupImage.swift
+++ b/Sources/ContainerTestSupport/WarmupImage.swift
@@ -23,6 +23,7 @@ public enum WarmupImage: String, CaseIterable, Sendable {
     case alpine320 = "ghcr.io/linuxcontainers/alpine:3.20"
     case alpine318 = "ghcr.io/linuxcontainers/alpine:3.18"
     case busybox136 = "ghcr.io/containerd/busybox:1.36"
+    case pythonAlpine = "docker.io/library/python:alpine"
     case kindestNodeV1_35_5 = "docker.io/kindest/node:v1.35.5@sha256:ce977ae6d65918d0b58a5f8b5e940429c2ce42fa3a5619ec2bbc60b949c0ac95"
 
     /// Directory under app-root holding OCI tar archives of each warmup image.
diff --git a/scripts/install-init.sh b/scripts/install-init.sh
index e8a3c5689..339ab026a 100755
--- a/scripts/install-init.sh
+++ b/scripts/install-init.sh
@@ -70,13 +70,18 @@ if [ "${CONTAINERIZATION_VERSION}" == "unspecified" ] ; then
 	fi
 	echo "Creating InitImage"
 	make -C ${CONTAINERIZATION_PATH} init
-	${CONTAINERIZATION_PATH}/bin/cctl images save -o /tmp/init.tar ${IMAGE_NAME}
+	# The tar stays in bin/ so the integration recipe can land the image
+	# again into whichever store the tests run against.
+	${CONTAINERIZATION_PATH}/bin/cctl images save -o bin/init.tar ${IMAGE_NAME}
 
 	# Sleep because commands after stop and start are racy.
 	bin/container system stop
     sleep 3
-	bin/container --debug system start "${START_ARGS[@]}"
+	# A start against a data directory with no configured kernel asks on
+	# stdin whether to install one, and this runs from make with no
+	# terminal, so the flag answers instead of a prompt, the way the
+	# integration recipe's own start does.
+	bin/container --debug system start --enable-kernel-install "${START_ARGS[@]}"
 	sleep 3
-	bin/container i load -i /tmp/init.tar
-	rm /tmp/init.tar
+	bin/container i load -i bin/init.tar
 fi