diff --git a/Dockerfile b/Dockerfile
index 6ed111f5b2..ee2c491c06 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -55,6 +55,29 @@ RUN npm install --prefer-offline --no-audit && \
     (cd ui-tui && npm install --prefer-offline --no-audit) && \
     npm cache clean --force
 
+# ---------- Layer-cached Python dependency install ----------
+# Copy only pyproject.toml + uv.lock so the Python dep resolve + wheel
+# download + native-extension compile layer is cached unless those inputs
+# change.  Before this split the Python install sat after `COPY . .`, so
+# every source-only commit re-did ~4-5 min of dep work on cold builds.
+#
+# README.md is referenced by pyproject.toml's `readme =` field, but it's
+# excluded from the build context by .dockerignore's `*.md`.  uv's build
+# frontend stats the readme path during dep resolution, so we `touch` an
+# empty placeholder — the real README is restored by `COPY . .` below.
+#
+# `uv sync --frozen --no-install-project --extra all` installs only the
+# deps reachable through the composite `[all]` extra (handpicked set
+# intended for the production image).  We do NOT use `--all-extras`:
+# that would pull in `[rl]` (atroposlib + tinker + torch + wandb from
+# git), `[yc-bench]` (another git dep), and `[termux-all]` (Android
+# redundancy), none of which belong in the published container.
+#
+# The editable link is created after the source copy below.
+COPY pyproject.toml uv.lock ./
+RUN touch ./README.md
+RUN uv sync --frozen --no-install-project --extra all
+
 # ---------- Source code ----------
 # .dockerignore excludes node_modules, so the installs above survive.
 COPY --chown=hermes:hermes . .
@@ -77,9 +100,10 @@ RUN chmod -R a+rX /opt/hermes && \
 # Start as root so the entrypoint can usermod/groupmod + gosu.
 # If HERMES_UID is unset, the entrypoint drops to the default hermes user (10000).
 
-# ---------- Python virtualenv ----------
-RUN uv venv && \
-    uv pip install --no-cache-dir -e ".[all]"
+# ---------- Link hermes-agent itself (editable) ----------
+# Deps are already installed in the cached layer above; `--no-deps` makes
+# this a fast (~1s) egg-link creation with no resolution or downloads.
+RUN uv pip install --no-cache-dir --no-deps -e "."
 
 # ---------- Runtime ----------
 ENV HERMES_WEB_DIST=/opt/hermes/hermes_cli/web_dist