- A discussion of “technology trees for the 21st century” asked for a cohesive, step-by-step dependency graph that would let a community bootstrap modern prosperity from raw materials, covering mining, smelting, agriculture, and ending with products such as computers or estradiol.  
- The historical SKDB (System Knowledge Database) project—last active ~2010—was pointed to as the closest prior attempt; it stored machine and material data in YAML and used OpenCASCADE to auto-assemble Lego-like CAD models as a proof-of-concept for physical dependency resolution.  
- Participants debated realistic starting assumptions: whether one must literally knap the first stone tools or can begin with scavenged artifacts, and whether post-collapse communities could surpass Iron-Age limits given today’s depleted easily-accessible ores and energy.  
- Concrete machine tools were highlighted as a forgotten WWII-era bootstrap technology—easier to cast than iron yet abandoned once conventional industry recovered—illustrating how economic context, not pure engineering, often dictates technological “choice.”  
- The “Foundations of Mechanical Accuracy” (Wayne Moore) and Dave Gingery’s DIY machine-tool books were recommended as canonical references for achieving precision without modern industry.  
- A proposed video-game/simulation was outlined that would let players explore technology dependencies in different scenarios (e.g., “build a laptop in ancient Rome” or “3-D-print parts ordered from Amazon”), crowdsourcing missing data via “why can’t I build X? patches welcome.”  
- Bootstrapping software was used as an analogy: TinyCC can be hand-entered to compile GCC, paralleling the idea of a minimal physical toolkit that can iteratively build more advanced tools.  
- Metformin’s association with lower COVID-19 mortality in diabetics (PMID 32446312) and a Reddit update on rapamycin life-extension trials in dogs were shared as contemporary longevity datapoints.