macOS: uv run panics inside SystemConfiguration when sandboxed (Codex/seatbelt) — "Attempted to create a NULL object" #16664
Description
Summary
IMPORTANT: This is a major blocker for running Python through uv in OpenAI Codex on macOS.
When uv run is executed inside a macOS sandbox (e.g., OpenAI Codex’ default seatbelt or a minimal seatbelt profile), uv panics in Rust while initializing SystemConfiguration’s dynamic store. The process aborts before the target command (Python) starts.
I am not very knowledgeable about uv-seatbelt interaction, I have a feeling that there might be more than one issue here.
Reproduction A — inside Codex
Install codex v0.55.0, and ask it to run run uv run python -c "print('hello')"
/ T R A N S C R I P T / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / /
╭────────────────────────────────────────────────╮
│ >_ OpenAI Codex (v0.55.0) │
│ │
│ model: gpt-5-codex high /model to change │
│ directory: ~/copies/platform-2 │
╰────────────────────────────────────────────────╯
To get started, describe a task or try one of these commands:
/init - create an AGENTS.md file with instructions for Codex
/status - show current session configuration
/approvals - choose what Codex can do without approval
/model - choose what model and reasoning effort to use
/review - review any changes and find issues
› run uv run python -c "print('hello from backend dir')"
• Preparing to run backend Python command
$ uv run python -c "print('hello')"
thread 'main2' panicked at /Users/runner/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/system-configuration-0.6.1/src/dynamic_store.rs:154:1:
Attempted to create a NULL object.
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
thread 'main' panicked at /Users/runner/work/uv/uv/crates/uv/src/lib.rs:2409:10:
Tokio executor failed, was there a panic?: Any { .. }
✗ (101) • 133ms
Note that I cannot reproduce it in every folder. It doesn't raise an error when I open codex in /tmp directory.
Reproduction B — pure macOS seatbelt
Save the following in a file repro.sh and run it:
cd /tmp && mkdir uv-sandbox-test && cd uv-sandbox-test
# Sandbox profile blocking SystemConfiguration
cat > block-sysconfig.sb <<'EOF'
(version 1)
(allow default)
(deny mach-lookup (global-name "com.apple.SystemConfiguration.configd"))
EOF
# Create project and run from inside it
uv init test-project
cd test-project
env RUST_BACKTRACE=full sandbox-exec -f ../block-sysconfig.sb \
uv run python -c "print('hello')"I am not sure this is the EXACT same error or seatbelt configuration on Codex that causes this error, but it seems very relevant.
Output:
Mac :: /tmp » bash repro.sh
mkdir: uv-sandbox-test: File exists
Initialized project `test-project` at `/private/tmp/test-project`
Using CPython 3.13.7
Creating virtual environment at: .venv
thread 'main2' panicked at /Users/runner/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/system-configuration-0.6.1/src/dynamic_store.rs:154:1:
Attempted to create a NULL object.
stack backtrace:
0: 0x105545e44 - __mh_execute_header
1: 0x1051faaf0 - __mh_execute_header
2: 0x105545684 - __mh_execute_header
3: 0x105545ce4 - __mh_execute_header
4: 0x10554526c - __mh_execute_header
5: 0x105544894 - __mh_execute_header
6: 0x105544864 - __mh_execute_header
7: 0x106ccc22c - __mh_execute_header
8: 0x10542e094 - __mh_execute_header
9: 0x10642a55c - __mh_execute_header
10: 0x106428374 - __mh_execute_header
11: 0x106458ba4 - __mh_execute_header
12: 0x105067c70 - __mh_execute_header
13: 0x10505e190 - __mh_execute_header
14: 0x10504aaa8 - __mh_execute_header
15: 0x104f99274 - __mh_execute_header
16: 0x104fa7368 - __mh_execute_header
17: 0x10510c2b0 - __mh_execute_header
18: 0x106028388 - __mh_execute_header
19: 0x105d1441c - __mh_execute_header
20: 0x10557d99c - __mh_execute_header
21: 0x184a72c0c - __pthread_cond_wait
thread 'main' panicked at /Users/runner/work/uv/uv/crates/uv/src/lib.rs:2409:10:
Tokio executor failed, was there a panic?: Any { .. }
stack backtrace:
0: 0x105545e44 - __mh_execute_header
1: 0x1051faaf0 - __mh_execute_header
2: 0x105545684 - __mh_execute_header
3: 0x105545ce4 - __mh_execute_header
4: 0x10554526c - __mh_execute_header
5: 0x10557835c - __mh_execute_header
6: 0x1055782cc - __mh_execute_header
7: 0x10557d4c0 - __mh_execute_header
8: 0x106cb105c - __mh_execute_header
9: 0x106cb144c - __mh_execute_header
10: 0x105fa9d08 - __mh_execute_header
11: 0x105cbe994 - __mh_execute_header
12: 0x106026538 - __mh_execute_header
13: 0x105cbecec - __mh_execute_header
Other issues
On Codex side: openai/codex#1457
Platform
macOS 15.5 arm64
Version
uv 0.9.7 (0adb444 2025-10-30)
Python version
Python 3.13.7