Dear all, some of you may be aware that we've been working on a new form compilation pipeline, in an endeavour to provide proper support for non-affine elements. We're now pretty much ready to do so, and the new code should arrive by the end of the week. A further announcement will occur at that point, with instructions on how to update. Some points to note: The new compiler applies all pullbacks and geometric transformations symbolically. This means that on non-affine elements, you get (depending on form), more than just jacobians, but also derivatives thereof. Previously on quadrilaterals (and extruded meshes) we used an approximation of a cell-wise constant Jacobian evaluated at the cell midpoint. This may therefore result in larger execution times, since the assembly of forms now does more work. On affine elements, this will not be the case. We therefore do not expect to see much difference in performance on simplexes: in our tests, there has been at most 10% slowdown, which we hope to address in the coming weeks. If your code starts running noticeably slower as a result of these changes, please please please let us know via the usual routes (either the mailing list, or by reporting a github issue) so that we can debug the problem and fix it. Cheers, Lawrence