Correct but it’s even more (1) is more like using the client side code on the server AND the client at the same time, significantly reducing duplication of effo

Correct but it’s even more (1) is more like using the client side code on the server AND the client at the same time, significantly reducing duplication of effort and offering the best of both worlds So you have one view library (and routing/models etc) and the innovation is that a) it very intelligently only delivers the bare minimum JS of what’s needed to make a fully interactive front end app (which is why you needed React/Vue in the first place due to limitations of pure server side code) plus b) using the same patterns and awesome libraries everywhere on your site, not just specific interactive components but blog, about pages, admin panels, etc. So you’re not doing python jinja or Ruby ERB templates/helpers/routes/etc on the server mixed with tons of duplication with React/Vue on the client.