Comment by austin-cheney

Here is a study on performance that I did for JavaScript in the browser: https://github.com/prettydiff/wisdom/blob/master/performance...

TLDR; full state restoration of a OS GUI in the browser under 80ms from page request. I was eventually able to get that exact scenario down to 67ms. Not only is the state restoration complete but it covers all interactions and states of the application in a far more durable and complete way than big JavaScript frameworks can provide.

Extreme performance showed me two things:

1. Have good test automation. With a combination of good test automation and types/interfaces on everything you can refactor absolutely massive applications in about 2 hours with almost no risk of breaking anything.

2. Tiny performance improvements mean massive performance gains overall. The difference in behavior is extreme. Imagine pressing a button and what you want is just there before your brain can process screen flicker. This results in a wildly different set of user behaviors than slow software that causes users to wait between interactions.

Then there are downstream consequences to massive performance improvements, the second order consequences. If your software is extremely fast across the board then your test automation can be extremely fast across the board. Again, there is a wildly different set of expectations around quality when you can run end-to-end testing across 300 scenarios in under 8 seconds as compared to waiting 30 minutes to fully validate software quality. In the later case nobody runs the tests until they are forced to as some sort of CI step and even then people will debate if a given change is worth the effort. When testing takes less than 8 seconds everybody and their dog, including the completely non-technical people, runs the tests dozens of times a day.

I wrote my study of performance just a few months before being laid off from JavaScript land. Now, I will never go back for less than half a million in salary per year. I got tired of people repeating the same mistakes over and over. God forbid you know what the answer is to cure world hunger and bring in world peace, because any suggestion to make things better is ALWAYS met with hostility if it challenges a developer's comfort bubble. So, now I do something else where I can make just as much money without all the stupidity.