combisurf is a Python package in active development for working with cell decompositions of surfaces in SageMath. It currently contains code for

• exhaustive and random generation of combinatorial maps (aka combinatorial surfaces, ribbon graphs or embedded graphs) as well as decorated such maps (coloration, spanning tree, etc)
• topology of curves and curve systems (simplicity test, homotopy test, geometric (self-)intersection, etc)
• drawings (2D and 3D projections)

In the near future, we aim to implement code related to

• simple curves, measured foliations and curve complex
• flip graphs and mapping class group

combisurf is free software, released under the GPL v2 (or later).

We welcome any help to improve combisurf. If you would like to help, have ideas for improvements, or if you need any assistance in using combisurf, please don't hesitate to contact us.