We had weekly releases to production. during my first month I checked in some code without yet fully understanding the spaghetti'ness of the 20 year old codebas

We had weekly releases to production. during my first month I checked in some code without yet fully understanding the spaghetti'ness of the 20 year old codebase. it turned out that our beta testers found a lot of cases that were broken on Friday when the release was next Monday. The problem was that a ton of other classes pointed to the one in which I made changes and altered the state.. Worked through the weekend with my teamlead and got it fixed somewhere on sunday afternoon. good bonding experience though. All had a laugh about it the next week. :-)