If you own a Prusa XL, you know the deal. It's a fantastic machine with a unique modular bed, a tool changer system, and engineering that puts it in a class of its own. But if you've ever wanted to run Klipper on it, you've been out of luck. The XL's architecture is complex — five independent Dwarf toolheads communicating over MODBUS, a segmented heated bed, loadcell-based probing — and none of that plays nice with a standard Klipper install.Until now.TinkerAtlas member racoutlaw (Richard Crook) just launched KlipperXL — a full Klipper firmware replacement for the Prusa XL that supports all five toolheads, the modular bed, loadcell probing, and pretty much every feature the stock firmware offers. And it's open source under the GPL.This is the kind of project that makes me excited about what our community is building.What Is KlipperXL?At its core, KlipperXL replaces the stock Prusa firmware on the XLBuddy mainboard with Klipper, giving you full control through Mainsail or Fluidd. That alone would be impressive enough, but what makes this project stand out is the depth of implementation. Richard didn't just get Klipper running on the XL — he built a complete system that handles the things that make the Prusa XL uniquely challenging.The five Dwarf toolheads? They communicate via MODBUS over RS485, and KlipperXL speaks the same protocol Prusa's firmware uses. The Dwarfs don't need any modifications — they run stock Prusa firmware. A custom Python host module handles the entire boot sequence, tool changes, heater management, loadcell probing, filament detection, and calibration.The modular bed with its 16 individually controlled heating zones? Fully supported, with adaptive heating that only powers the zones under your actual print area and applies gradient heating to adjacent zones to prevent warping. You can pull up a live 4x4 temperature heatmap right in your Mainsail dashboard.The HighlightsThere's a lot packed into this project, but here are the things that stood out to me.Full Tool Changer SupportAutomatic tool changes with Prusa-matched dock sequences, including pick, park, and a wiggle retry if the dock doesn't seat properly. There's tool offset calibration using the Prusa calibration pin, multi-color and multi-material printing with slicer-managed temperatures and wipe tower support, and a spool join feature that actually improves on the stock firmware. When a tool runs out of filament mid-print, KlipperXL lets you pick a different tool to continue with right then and there — no need to configure that before you start printing like you would on stock. You make the call when it's needed, which is just more practical.Loadcell ProbingThe Prusa XL uses loadcells built into the Dwarf toolheads for Z homing and bed mesh leveling. KlipperXL supports this fully, with adjustable probe thresholds for Z homing, mesh leveling, and XY calibration. You can tweak the sensitivity right from Mainsail without touching config files.Adaptive EverythingAdaptive bed mesh probes only the area your print actually covers. Adaptive bed heating powers only the bedlets under and around your print. These are the kinds of features that save time and energy on every single print.LED Status EffectsKlipperXL uses klipper-led_effect by julianschill to drive the side LED strips, giving you different colors and effects for different printer states — idle, printing, heating, paused, error, and print complete. It's a small touch that makes a real difference when you're monitoring prints from across the room, and is much better than the stock firmware with it's white light.Input ShaperThe Dwarf toolheads have built-in accelerometers, and KlipperXL uses the first tool to measure resonance and apply input shaper compensation across all tools. You get the same print quality benefits Klipper users expect, running on hardware that was never designed for it.OrcaSlicer ReadyThe project comes with a pre-configured OrcaSlicer profile and macros. You start from the Generic Tool Changer profile, change four settings, and you're printing. Richard even includes calibrated starting points for pressure advance and input shaper values tuned on a 5-tool XL.Why This MattersThe Prusa XL is one of the most advanced consumer 3D printers on the market. Running Klipper on it has been a goal for a lot of people in the community, but the complexity of the hardware made it a massive undertaking. The MODBUS communication with the Dwarfs, the segmented bed, the loadcells — none of this is standard Klipper territory.Richard didn't just hack something together. The documentation includes a full technical specification with MODBUS register maps, motor pin assignments, TMC driver configurations, probe threshold calibration guides, and DFU recovery procedures. This is a proper engineering effort, released to the community as open source.For anyone who has been on the fence about buying a Prusa XL because of the locked-down firmware, or for current owners who want the flexib