function __auto_vent --on-variable PWD
    if test -f "$PWD/.venv/bin/activate.fish"
        source "$PWD/.venv/bin/activate.fish"
        return
    end

    if set -q VIRTUAL_ENV
        set -l project_dir (path dirname $VIRTUAL_ENV)
        if not string match -q "$project_dir" "$PWD" and not string match -q "$project_dir/*" "$PWD"
            deactivate 2>/dev/null
        end
    end
end