Discovered pro tip of my life :
Never trust your code

Achievements unlocked :
Successfully running C++ GPU accelerated offscreen rendering engine with texture loading code having faulty validation bug over a year on production for more than 1.5M daily Android active users without any issues.

History : Recently I was writing a new rendering engineering that uses our GPU pipeline engine.. and our prototype android app benchmark test always fails with black rendering frame detection assertion.

Practice:
Spend more than a month to debug a GPU pipeline system based on directed acyclic graph based rendering algorithm.

New abilities added :
Able to debug OpenGL ES code on Android using print statement placed in source code using binary search.

But why?
I was aware of the issue over a month and just ignored it thinking it's a driver bug in my android device.. but when the api was used by one of Android dev, he reported the same issue. In the same day at night 2:59AM ....

Satan came to me and told me that " ok listen man, here is what I am gonna do with you today, your new code will be going production in a week, and the renderer will give you just one black frame after random time, and after today 3AM, your code will not show GL Errors if you debug or trace. Buhahahaha ahhaha haahha..... Puffff"

And he was gone..
Thanks satan for not killing me.. I will not trust stable production code anymore enevn though every line is documented and peer reviewed.

My manager insists I use a debugger. Note to self, next time lie and say I use a debugger

Well, throughout my life I've never really thought about programming. Then one day during some downtime on a backpacking trip with a friend, while I had nothing to do my friend sat there with his computer with the screen all dark, filled with funny colourful text in lines of different length, with some lines even starting more towards the middle of the page than to the left, almost following a vertical wave pattern. He said he was writing a program to control his home remotly as well as working as a security feature that could unlock his home automatically when he got home. I was amazed by the colorful text as well as the fact that he could just create this crazy program out of nothing.
Half a year later I attended my first lecture at the computer science programme. My first program was a command line tool used for baking bread. It asked you how much flour you'd use and how many eggs, then it'd tell you wether or not you'd got the correct ratio. I was blown away by the intuitive nature of programming. I could imagine the control flow as a tree or flow chart in my head. I mean the whole program was only a couple of user inputs followed by an if-statement and a print-statement, but for me it was awe inspiring. I knew then that I'd probably chosen the right path in education.