I think I need to write a blog post to do a retrospective on what I learned writing iod, silicon, lithium (and vpp, a small image processing lib). There is so much to tell.

Just to be short, here is my phylosophy:

   - don't think too much when you write it the first time, just do it quick. Do all the mistakes and ugly code first and then rething/rewrite things when it can actually simplify the codebase. Big refactors are much more productive and successful than big premature design thinking.
   - Only expose the complexity that the user need. Simple things should stay simple even if we can do more complex stuff. Look for simplicity everywhere.
   - Profile before optimizing, the bottleneck is never where you think it is.

For you question about metaprogramming, it is used yes. The core of the framework is build around a compile time key/value map that unroll json and get/post parameter de/serialization at compile time [1] so no dynamic dictionary involving costly malloc is needed.

[1] https://github.com/matt-42/lithium/tree/master/libraries/met...

For Rust vs c++: - I never used rust but I like the language and the safety it provides.

  - a mainstream package/dependency manager is missing in C++ so rust is clearly better on this point. This is a big problem for the C++ community where code is much less shared than in the javascript community for example.
  - The other big problem I have with C++ is compile time, I heard that Rust is slow too but I never compared the two.

And what robotics stuff have you worked on?

I'm building a offline programming tool for industrial robots: http://stara-robotics.com/

High density point tracking and optical flow was a big part of my PhD, here is a demo :) https://www.youtube.com/watch?v=GIUDAZLfYhY