fun fact: in llarp paths are actually a pair of unidirectional flows in the shape of 2 double linked lists where a node is a router, one upstream, one downstream. there is no rule which says a path build record has to have the upstream flow and downstream flow for the same path. this means you can (in theory) interlace and mix build records so that the path build direction differs from the direction data travels and the set of routers that upstream flows use differs from downstream flows. all for free, no need to do weird stateful bullshiting like in tor.