MarlinFirmware/Marlin
Marlin is a firmware for RepRap 3D printers optimized for both 8 and 32 bit microcontrollers. Marlin supports all common platforms. Many commercial 3D printers come with Marlin installed. Check with your vendor if you need source code for your specific machine.
Outside contributors get real replies here, and their work gets merged.
41 of 91outside PRs merged (45%)
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Where newcomer work lands
The evidence