Stair stepping on flat top surfaces has been one of those annoyances that layer-based printing just accepts as normal. This build tackles it head on: a fork of Orca Slicer that bakes nonplanar slicing directly into the software, so top surfaces can follow the actual geometry instead of being flattened into terraces. The goal is smoother rounded features like chamfers and fillets, and from the demo on an A1 mini it looks promising, with a test plaque showing standard stepped layers right next to a smooth nonplanar finish.
The way it is put together is clever. The maker built the project using Claude Code (Opus 5.5), which is a bold development approach for a slicer fork. The workflow stays simple: slice the model in the fork, export the plate sliced file, then drop that file into any slicer to print. It can also be used alongside Bambu Studio. Printer support is broad, covering the Bambu A1 mini, A1, P1S, P2S, X1C, X2D and H2D, plus the Prusa MK4S, CORE One and XL 5T, the Elegoo Centauri Carbon 2 and the Creality K1C.
The stated limits are a maximum nonplanar angle of 12 degrees and a maximum height of 5 mm, and slicing can take anywhere from 5 seconds to 5 minutes depending on the model. For testing rounded surfaces, the suggested method is to add a Sphere primitive and slice it in half, which sounds like a quick way to judge the result.
There are real limitations to keep in mind. Right now the software only runs on macOS with Apple Silicon, and the Elegoo Centauri Carbon 1 and Snapmaker U1 do not work with it. One user also needed XQuartz to get it running, and version 27.2 threw a missing library error, Namespace DYLD, Code 1. The slicer is publicly available on GitHub for anyone who wants to poke at it.