Baby's Second Garbage Collector (matheusmoreira.com)

The article describes the evolution of a “Baby’s First Garbage Collector” in the Lone Lisp project into a more advanced collector that can recover escaped objects by scanning not just the Lisp stack but also the native stack beneath it. It explains how the collector marks reachable heap values efficiently, and how conservative assumptions and pragmatics are used to avoid quadratic checks. The author then notes that tests revealed remaining “missing” objects, leading to further investigation into places like CPU registers.