Here are several principles of developments.

0. A builder should not rely on another builder (just like the question "the chicken or the egg appears first"). So that:
   • We cannot use cmake, makefile or else as our builder.
   • We cannot import libraries who uses cmake, makefile or else as builder.
     • boost uses b2 (which only depends on bootstrap.sh that invokes the compiler and outputs a self-written builder) as builder.
     • stdexec or beman::execution are header-only, which only depends on cp command.
   • We should use as less commands as possible in the xxx-make script.