def serialize_task(row, users_by_id=None) -> dict:
    """`users_by_id` is one batched Users lookup done in views — never a lazy
    per-row load. Assignee name/role ride along so the screen can render the
    real user without a second request."""
    users_by_id = users_by_id or {}
    assignee = users_by_id.get(row.assignee_id)
    return {
        "id": str(row.id) if row.id else None,
        "title": row.title,
        "status": row.status,
        "priority": row.priority,
        "due_date": row.due_date.isoformat() if row.due_date else None,
        "assignee_id": str(row.assignee_id) if row.assignee_id else None,
        "assignee_name": assignee.name if assignee else None,
        "assignee_role": assignee.role.role_name if assignee and assignee.role else None,
        "inbox_id": row.inbox_id,
        "job_post_id": str(row.job_post_id) if row.job_post_id else None,
        "created_by": str(row.created_by) if row.created_by else None,
        "created_at": row.created_at.isoformat() if row.created_at else None,
        "updated_at": row.updated_at.isoformat() if row.updated_at else None,
    }