fix: mount .local/share to persist uv-managed Python installations

[TonyHernandezAtMS]

Description

Fixes broken Python venv symlinks after container restarts by mounting ~/.local/share/ to persist uv-managed Python installations.

Fixes #87

Problem

When uv creates a venv with --python-preference managed, it downloads Python to ~/.local/share/uv/python/. The venv contains symlinks pointing to this location, but since ~/.local/share/ was not mounted, the Python installation was lost on container exit, leaving broken symlinks.

Solution

Added mount for PROJECT_SLOT_DIR/.local/share in lib/docker.sh to persist uv-downloaded Python installations across container restarts.

+    # Mount .local/share for uv-managed Python installations
+    # uv downloads Python to ~/.local/share/uv/python/ which must persist across containers
+    mkdir -p "$PROJECT_SLOT_DIR/.local/share"
+    docker_args+=(-v "$PROJECT_SLOT_DIR/.local/share":/home/$DOCKER_USER/.local/share)

Testing

Tested on macOS with ml-tutorial project:

1. ✅ Clean project, add python ml profiles
2. ✅ First run: Python 3.14 downloads successfully (111 packages including torch, transformers, scikit-learn, pandas, numpy)
3. ✅ Verified Python installation persists on host: ~/.claudebox/projects/.../6111fd25/.local/share/uv/python/cpython-3.14.0-linux-aarch64-gnu/
4. ✅ Venv symlinks are valid and point to persisted Python
5. ✅ Subsequent container starts: Python works correctly

Impact

• Affects: python, ml, and datascience profiles
• Compatibility: macOS and Linux
• Breaking changes: None
• Performance: Negligible (adds one directory mount)

Related Issues

This bug was introduced in commit 57fa079 when Python installation was moved from build-time to runtime.

Subsequent commits attempted to fix Python issues but missed the root cause:

• 4fd05a8 - "Fix multiple issues: shell auth, Python/uv PATH..."
• b2aedd9 - "Fix multiple issues with Python/uv, tmux activation..."
• bcf4ee7 - "Add UV_PYTHON_MANAGED=1 environment variable"

[sourcery-ai]

Reviewer's guide (collapsed on small PRs)

Reviewer's Guide

Adds a host directory creation and Docker volume mount for ~/.local/share in the run_claudebox_container function to persist uv-managed Python installations and prevent broken venv symlinks across container restarts.

Flow diagram for persisting uv-managed Python installations

flowchart TD
    A["Container start"] --> B["Create $PROJECT_SLOT_DIR/.local/share on host"]
    B --> C["Mount $PROJECT_SLOT_DIR/.local/share to /home/$DOCKER_USER/.local/share in container"]
    C --> D["uv downloads Python to /home/$DOCKER_USER/.local/share/uv/python/"]
    D --> E["Python installation persists across container restarts"]

Loading

File-Level Changes

Change	Details	Files
Persist uv-managed Python installations by mounting ~/.local/share.	Create host directory $PROJECT_SLOT_DIR/.local/share if it doesn't exist Add docker_args entry to mount host .local/share into /home/$DOCKER_USER/.local/share	lib/docker.sh

Possibly linked issues

• #Python not available in containers issue: The PR fixes Python not persisting in containers by mounting ~/.local/share, as suggested in the issue, resolving broken venv symlinks.
• #123: The PR fixes the root cause of uv pip install failures by ensuring uv-managed Python installations persist through mounting .local/share.

---

Tips and commands

Interacting with Sourcery

• Trigger a new review: Comment @sourcery-ai review on the pull request.
• Continue discussions: Reply directly to Sourcery's review comments.
• Generate a GitHub issue from a review comment: Ask Sourcery to create an
  issue from a review comment by replying to it. You can also reply to a
  review comment with @sourcery-ai issue to create an issue from it.
• Generate a pull request title: Write @sourcery-ai anywhere in the pull
  request title to generate a title at any time. You can also comment
  @sourcery-ai title on the pull request to (re-)generate the title at any time.
• Generate a pull request summary: Write @sourcery-ai summary anywhere in
  the pull request body to generate a PR summary at any time exactly where you
  want it. You can also comment @sourcery-ai summary on the pull request to
  (re-)generate the summary at any time.
• Generate reviewer's guide: Comment @sourcery-ai guide on the pull
  request to (re-)generate the reviewer's guide at any time.
• Resolve all Sourcery comments: Comment @sourcery-ai resolve on the
  pull request to resolve all Sourcery comments. Useful if you've already
  addressed all the comments and don't want to see them anymore.
• Dismiss all Sourcery reviews: Comment @sourcery-ai dismiss on the pull
  request to dismiss all existing Sourcery reviews. Especially useful if you
  want to start fresh with a new review - don't forget to comment
  @sourcery-ai review to trigger a new review!

Customizing Your Experience

Access your dashboard to:

• Enable or disable review features such as the Sourcery-generated pull request
  summary, the reviewer's guide, and others.
• Change the review language.
• Add, remove or edit custom review instructions.
• Adjust other review settings.

Getting Help

• Contact our support team for questions or feedback.
• Visit our documentation for detailed guides and information.
• Keep in touch with the Sourcery team by following us on X/Twitter, LinkedIn or GitHub.

[sourcery-ai]

Hey there - I've reviewed your changes and they look great!

---

Sourcery is free for open source - if you like our reviews please consider sharing them ✨

• X
• Mastodon
• LinkedIn
• Facebook

_{Help me be more useful! Please click 👍 or 👎 on each comment and I'll use the feedback to improve your reviews.}