NEXO 7.13.9 — stale Desktop venv recovery

Published 2026-05-06. Patch release over v7.13.8 — closes the half-failed Desktop install path where a managed Python 3.9 virtual environment could survive and be reused.

Existing unsupported venvs are moved aside

Brain now checks the Python version inside the managed ~/.nexo/.venv before dependency installation. If that environment was created with Python older than 3.10, or the executable cannot be read, Brain moves the environment to an unsupported-python backup path and recreates it.

Desktop-prepared Python remains the source of truth

After the old environment is moved aside, Brain creates the new managed venv using the supported interpreter selected by Desktop through NEXO_BOOTSTRAP_PYTHON / NEXO_PYTHON. This prevents the installer from falling back into the same fastmcp failure caused by Apple Python 3.9.

Validation

node --check bin/nexo-brain.js
pytest -q tests/test_v6_fresh_install_skip.py
python3 scripts/verify_release_readiness.py --ci

Full changelog entry → · bin/nexo-brain.js · tests/test_v6_fresh_install_skip.py