flock is indeed built-in: `flock -xn /tmp/mylock.lock -c "echo running locked command"` does mutex locking in bash. Your tool might offer better ergonomics or f

flock is indeed built-in: `flock -xn /tmp/mylock.lock -c "echo running locked command"` does mutex locking in bash. Your tool might offer better ergonomics or features beyond flock's capabilities?