really describe decades of experience of thousands of chemists about when this reaction works, how well, with what yields, and when it might not work at all? On the last point, there is no way to incorporate into a (single) SMIRKS a condition for rejecting the reaction altogether. We therefore tapped into the source of synthetic transform knowledge with arguably the richest description of the chemical context for each reaction: the knowledgebase that underlies the computational embodiment of E.J. Corey's seminal work on retrosynthetic analysis, the program LHASA (Logic and Heuristics Applied to Synthetic Analysis) . A thorough review of knowledge-based expert systems in chemistry has been recently published. One of the characteristics distinguishing SAVI from LHASA is the fact the while the latter is retrosynthetic, the former is strictly forward-synthetic. This implied the task to make LHASA transforms, which are written for retrosynthetic application, work in a forward-synthetic context (A forward-synthetic application of the LHASA rules, LCOLI, was reported in the early 2000s but doesn't seem to have progressed to any widely used tool.).