Thanks for the great question, and for checking out the project! This project started out because I noticed some really interesting properties about compiling brainfuck-like programming languages while writing high level language compilers that targeted these brainfuck-like backends.
This is the work that inspired Sage: Harbor (https://github.com/adam-mcdaniel/harbor). My goal with Sage was to take everything that makes a brainfuck-like programming language easy to compile, while also keeping all the time complexity and optimizations of regular algorithms. So, in that sense, it started out as an attempt to design around a Turing machine -- I wanted this to be a dialect of brainfuck. The VM doesn't use any stack operations, just operations on a tape pointer + an accumulator!
This is the work that inspired Sage: Harbor (https://github.com/adam-mcdaniel/harbor). My goal with Sage was to take everything that makes a brainfuck-like programming language easy to compile, while also keeping all the time complexity and optimizations of regular algorithms. So, in that sense, it started out as an attempt to design around a Turing machine -- I wanted this to be a dialect of brainfuck. The VM doesn't use any stack operations, just operations on a tape pointer + an accumulator!