I like to code in a way which is considerate to the machines which will be running that code.
For me this means using bespoke code, as this way it can be written with this aim in mind. If you think of a cluttered room full of items which are useful, but messy and all over the place, this is very typical for a lot of the code I have seen over my career. With many inputs and updates, often done in a rush, it is not the ideal code for speed.
The code running the website machine used by our company, is written to be fast. Numbers are used instead of letters wherever possible ( and without being too confusing ) in the code ( behind the scenes )
Libraries were created to keep the code organised, so in can easily be maintained.
The lightest framework we could find and work with conveniently has been used.
Our Admin section uses code which is downloaded once and runs from the users computer. This gives an experience which has very little lag, as compared to many traditional systems which require a lot of patience and time to administrate and update.
I like to keep an eye on progressions in the technology which will keep the performance fast. Our system is currently in the top 25 percent of websites in the world for speed.