Can of Worms
Noun · Hacker Culture
Definitions
An idiom for a topic or change likely to uncover many new complications once opened. In engineering culture it often describes legacy systems, migrations, or 'small fixes' that hide deeper structural issues.
In plain English: A problem area that will create many more problems once you open it up.
Example: "Changing that one auth assumption looked simple until someone pointed out it would open a whole can of worms around session invalidation and API compatibility."