From the perspective of an rr maintainer, Sid's work was good and we were supportive of it. The main issues with migrating to that as the "blessed" version are

From the perspective of an rr maintainer, Sid's work was good and we were supportive of it. The main issues with migrating to that as the "blessed" version are that 1) rr has accumulated a decade of very hairy fixes for crazy kernel/process behavior that we feared could be lost during a port and 2) there's a closed source project (remix[0]) built on top of rr that would have needed to be ported too. [0] https://robert.ocallahan.org/2020/12/rr-remix-efficient-replay-only-binary.html https://robert.ocallahan.org/2020/12/rr-remix-efficient-repl...