This is an extension to classic BPF, Berkeley Packet Filter, in a way which is alternative to Linux' eBPF. The project is currently in a designing stage.
See bpf64spec.md for draft of Specification, and motivation (explanation of eBPF problems).
The nuc_ts_prog_kern.c (and it's include nuc_ts_common_kern_user.h) is XDP/eBPF program (for Linux 6.5) for parsing TCP packet and incrementing it's Timestamp option, if any, recording statisitics intop eBPF map.
The nuc_ts_incr.baw (and it's include nuc_ts_incr.bah) is the equivalent program doing the same thing, but in a new BPF64 Assembler Wrapper language, not yet written and subject to change. Note this is a lower-level language than C, viewed as intermediate solution until BPF64 becomes stable, after which more higher-level language (higher than C) should be written, at least as expressible as tcpdump (libpcap) one.
The fbpf_rus.txt was recording of thinking/designing process at it first 2 months while living as GitHub gist, it's raw, in mix of languages and not for the faint of heart (alas, Git is not good for recording of thinking, not code).
The code is assumed to be written later when specification becames somewhat settled after discussion in BSD mail lists.