None of these proteins, save for S2, are of unprecedented Max Path (to our knowledge, the longest path length in any published bracket is 9, from a large protein assembled in nearlinear fashion ). Obtaining acceptable yields of product protein over this many sequential yield losses, however, requires starting segments to be produced at large scale. In addition to the tools we have already described, the synthesis of these proteins may rely on additional protein engineering, such as introducing acceptable mutations to provide additional ligation sites or splitting into independent subunits that can associate non-covalently to form a functional complex. The combination of both approaches has been demonstrated in some of the most complex syntheses to date, and these methods provide further opportunities for computational assistance to predict optimal mutations and/or stable sub-domains. Furthermore, this analysis highlights the need for continued development of new synthesis tools, both to enhance poor-yielding ligations and unlock alternative ligation sites.