A senior monk who was jealous of the nun Zjing’s recent promotion decided to spy on her work. Opening a recent project, he was astonished to find her code a confusing mess, riddled with obvious bugs. He notified master Banzen.

The old master thanked the monk for his diligence and bade him remain a moment. Banzen then called young master Zjing and put her on speaker.

“Say something about this ‘mouse’ project you created,” ordered Banzen.

“It is of exceedingly poor design,” said Zjing.

The senior monk smiled with satisfaction.

Banzen asked, “How poor?”

“This morning, our Software Quality Assessment tools found three hundred and eight separate deficiencies,” replied Zjing.

“That is a problem,” said Banzen. “If memory serves, they should have found three hundred and twenty.”

“Correct,” said Zjing. “Someone appears to have deactivated the rules which detect resource leaks. The project’s self-test notified me; I am investigating.”

Banzen bid her good hunting and turned to the monk. “If ever you fear there are mice in your walls, listen to common wisdom and buy four fine cats. But listen to Zjing also, and release a single mouse among the cats every day—to make certain they have not forgotten how to hunt.”