We are developing a B2B platform on Magento 1.x with a lot of custom-built modules. Upgrading on Magento 2 will be an enormous effort. Therefore we would like to develop on Magento 1.x longer than 3 years after Magento 2 is released.

Is it predictable if the security of Magento 1.x systems will be seriously affected when the support ends?

closed as primarily opinion-based by brentwpeterson, Keyul Shah, 7ochem, liyakat, Marius Oct 17 '15 at 13:45

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.