@lavergnetho@pyOpenSci@scientific_python@turingway I suppose the best mentors are those in the trenches; unfortunately, they are also heavily oversubscribed. Mentorship is inherent to the contributing process; the team helps newcomers to incorporate their changes into the project, and the skills transferred are often passed forward in a similar manner. Many projects in the ecosystem also participate in more targeted annual programs, such as #GSoC and #outreachy.
pyOpenSci