Update CONTRIBUTING.md

I added a section on performance

CONTRIBUTING.md

@@ -82,6 +82,22 @@ Often the simplest code is easier to read, easier to maintain and more efficient
 - Use the simplest data structure for the job: e.g. use a slice instead of List if you know the size upfront
 - Don't make things public if they don't need to be
 
+## A note on performance optimizations
+
+I like to follow Casey Muratori's optimization philosophy as outlined here: https://www.youtube.com/watch?v=pgoetgxecw8
+
+The most important optimization technique he mentions is non-pessimization, not needlessly making things worse.
+This mostly overlaps with the points from above. Some example for this are:
+- use the right data structure (don't force the square block through the circular hole), this may seem trivial, but often as code grows you may find yourself in a situation where the original data structure doesn't really fit anymore
+- use the simplest data structure for the job, e.g. Use an array list or circular buffer instead of a linked list or queue
+- keep data/object dependencies at a minimum, if you can put things flat into memory or on the stack without a pointer on the heap, then that's simpler and faster.
+- use f32 if you don't need the precision of f64
+- don't store things as zon if they don't need to be human readable, just use binary
+- always lock mutexes in the tightest possible scope
+
+The next important thing is to avoid fake optimizations, if you optimize something you must measure it in a realistic setting (and be mindful about measuring errors: https://www.youtube.com/watch?v=r-TLSBdHe1A ).
+Otherwise you may just end up with a more complicated and slower thing.
+
 ## Follow the style guide
 
 Most of the syntax is handled by a modified version of zig fmt and checked by the CI (see the formatting section above).
@@ -128,5 +144,5 @@ With a quick check you can ensure that you didn't add any unintended changes.
 
 With a more thorough review of your changes you can sometimes catch small mistakes, leftover TODOs or random debug code.
 
-And of course make sure to check the CI results, you should also get an e-mail notification if the CI fails.
+And of course make sure to check the CI results, you should also get an e-mail notification if the CI fails. **I will not review a PR if the CI failed!**