Build tools needed for makefile from build.sh early #3
Description
build.sh includes most of the tools that would be needed to run itself or the makefile, however it does not include zstd until phase 5, which is required for said makefile. All other dependencies seem to be available around phase 2, mostly through busybox. By building zstd earlier, it could enable aborting the bash script earlier and switching to the makefile without using host packages.
P.S. most of the tools needed are also available through nixpkgs minimal-bootstrap, at least for i686, with notable exceptions of zstd again, as well as wget. The fact that the minimal-bootstrap doesn't include busybox makes things a decent bit more complicated, but at least the other tools can be added to the shell separately. Dependency on a host wget could be reduced by downloading sources in two phases, one to get gnumake and busybox, and then a separate phase to download the rest using the implementation from busybox.