Dynamic polyimine-amide networks with exceptional properties, including high flexibility, excellent thermal stability and dual closed-loop circularity were designed by combining dynamic covalent imine-functionalities with amide-chemistry. The solvent free up-scalable synthesis started from carboxyl-functionalization of lignin-derivable aldehydes followed by melt polycondensation with a triamine to form two dynamic networks (PIAX1 and PIAX2, respectively). While previously reported vanillin-derived polyimine thermosets were typically non-flexible and brittle, our polyimine-amides are flexible with elongation at break 380 % for PIAX1 and 65 % for PIAX2, where the higher flexibility of PIAX1 is deduced to the lower glass transition temperature and crosslinking density. Both materials illustrate fast stress relaxation even at low temperature, down to 50 °C in the case of PIAX1. Retained and even improved mechanical properties were observed after several cycles of thermal reprocessing, e.g., after three reprocessing cycles by hot pressing, PIAX1 recovered 116 % of original tensile stress and 126 % of original elongation at break, while chemical recycling under acidic conditions at room temperature yielded repolymerizable trialdehydes and triamines. Furthermore, rapid self-healing and shape memory behaviour at low temperature were demonstrated for PIAX1. A promising molecular design, further tuneable by choice of aldehyde and triamine, is demonstrated enabling high performance and dual closed-loop circularity.