There is no such thing as a "Random Error".
Unless you are using rand() to select a random index from an array. And you forget to add - 1 to the generated index.
Now that is one hell of a random error!

Image implementing angular universal which for it self is quite painful... Timeinvestment 8hours
Testing local 12 hours by the team
.. deploying to Google app engine because we need a nodejs server and we do don't have one yet ... Server crashing 24/7 with random errors most are memory related spend 3 days almost rewriting everything ... trying to find the memory leak
Then when I was about to give up stumble over a GitHub issue where someone is saying something about tiers on app engine.
Me going wtf there are tiers everywhere it just says automatically scaling instances ...
Googling .. setting to highest tier .. app works. Apparently I was in lowest tier which only has 156 MB ram app needs 150- 250 MB. Me now crying in corner about my wasted 4 days.