I had to drill open a bank vault for Bank of Canada's cash depot once. The vault engineer who knew the operation and diagram was an 80 year old vault tech who passed away a month prior. To bring you up to the vaults used in the cash depots (cash trucks come daily to deliver 1/x https://twitter.com/cryptoishard/status/1248087790807638016

.. this money across the country) this vault cannot be opened from the inside, it's classification determines for safety reasons because the size of the vault room's (You can play basket ball in some of these), that a thief could hide inside the vault room behind a rack 2/x

.. and unlock the vault in the middle of the night when the cash depot is closed (supposedly because they run 24/7 anyway). The Bank of Canada was losing roughly 1 million dollars per hour and the vault tech they hired before me made a bigger mess of the problem. 3/x

The other vault tech used a 10 ton car jack, bolted it ton the floor and attempted to push the vault door closed by force. If you know anything about safes or vaults you never force the door closed because something could be stuck between the door and frame and it makes it 4/x

.. a bigger problem. Unfortunately that wasn't the case, instead this vault door had a large screw mechanism controlled by a very large wheel you rotate on the outside of the door. This screw about the radius of a football is what the door grabs onto, and then with the wheel 5/x

.. the door pulls itself shut as it spins this giant nut around the bolt pulling the vault door closed against the frame. Now when this other vault tech put 10 tons of pressure against this mechanism, they cross threaded the giant screw and nut. Yes you heard that right... 6/x

I got the vault door opened in a timely fashion by being incredibly smart on my penetration approach. But that is not what this thread is about, it's about people using technology they don't fucking know, eg. COBOL. Make sure whoever you hire knows what they are doing. 7/x

Don't let some noob with 20 years cross thread your vault door shut and lose you 8 million dollars. (That was the final loss of the bank from start to finish, that tech's work time and mine from the time the door was shut). 8/8