Ultimaker Cura
Most popular 3D printing slicer by Ultimaker
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Open Source tools and resources
A focused list of resources connected to Open Source. Useful when you already know the kind of problem you are trying to solve and want fewer tabs open.
PrusaSlicer
Advanced 3D printing slicer by Prusa Research
OrcaSlicer
Advanced slicer for power users with rapid development
Awesome 3D Printing
Curated GitHub list of 3D printing resources
FreeCAD
Open-source parametric CAD
Blender
Open-source 3D creation suite