diff --git a/Dockerfile.astera b/Dockerfile.astera
index 4ff01a8a..3bfb7ba2 100644
--- a/Dockerfile.astera
+++ b/Dockerfile.astera
@@ -26,6 +26,35 @@ ENV DEBIAN_FRONTEND=noninteractive \
     SHELL=/bin/bash \
     SAMPLEWORKS_PIXI_PROJECT_DIR=/app \
     SAMPLEWORKS_REQUIRE_PREBUILT_PIXI=1 \
+    SAMPLEWORKS_SKIP_ENV_PREPARE=1 \
+    EXT_REPLAY_BASE_IMAGE=${PIXI_WITH_CHECKPOINTS_IMAGE} \
+    PIXI_CACHE_DIR=/var/cache/pixi
+
+# Keep pixi's cache off the NFS-backed home volume.
+#
+# ACTL mounts $HOME from an nfs-shared PVC whose export squashes every write to
+# nobody (65534), while the workspace container runs as root. pixi puts uv's git
+# cache under its own cache dir, so a `git+https://` dependency gets cloned into
+# a tree root does not own, and git refuses to touch it:
+#
+#   fatal: detected dubious ownership in repository at
+#   '/home/dev/.cache/rattler/cache/uv-cache/git-v0/db/<hash>'
+#
+# which surfaces as an unrelated-looking "failed to solve the pypi requirements"
+# and blocks any environment with a git dependency (protpardelle, today).
+#
+# `git config --global --add safe.directory` is not a usable fix here: this
+# image ships git 2.34.1, where only an exact path or the bare `*` is honoured —
+# prefix globs are silently ignored (verified). The cache paths are
+# content-hashed, so exact entries are whack-a-mole, and `*` would disable the
+# ownership check on genuinely shared volumes like /mnt/diffuse-shared too.
+#
+# pixi already redirects its repodata and pypi-mapping caches off network
+# filesystems on its own; it just does not do the same for the uv cache. Setting
+# the cache root to container-local disk covers all of them. The trade-off is
+# that the download cache no longer survives a pod restart — environments
+# themselves live in the synced checkout and are unaffected.
+RUN mkdir -p /var/cache/pixi
     SAMPLEWORKS_SKIP_ENV_PREPARE=1
 
 RUN apt-get update && apt-get install -y --no-install-recommends \