I believe Lua would fit our needs for the language of choice for a rollups high-level framework. It is a scripting language with good performance and low memory footprint, which is very suited for an embedded system like the Cartesi Machine. Moreover, one of Lua’s core pillars is easy development, so it is an excellent language for newcomers.
Lua is also easily extensible through C modules!
Writing performance-critical code? C has you covered.
Interacting with Linux? You can write it in C.
Interacting with any third-party library with a C interface? You can do that as well.
Besides, the Lua C API is well documented and very easy to use.