The tech stack at Akamai is almost entirely proprietary. The company does let teams integrate open source and new tech as they see fit, but the process is very slow. Basic solved problems like continuous build and integration seem like unmoveable behemoths, even though they are not. Technical debt is rising and the company leadership has explicitly admitted that they are prioritizing revenue streams over any sort of technical debt reduction or mitigation. Over the past 5 years the company has gone from a fairly nimble if a bit introspective organization to a profit hungry big business.
There are a few departments that seem to be guided by randomly throwing darts at a board with no thought to how it will affect other units. Communication between business units is poor to non-existent.