I was asked to give a talk today at our informal type theory seminar in Budapest and chose to present (and hopefully not misrepresent) nprofile1qyt8wumn8ghj7un9d3shjtnyd968gmewwp6kytcqyz4g9497lls2ey4v3rxtld6a8m5rh7meav97tqfhnceyja6wn0lpgng99up (nprofile…99up) and James E. Hanson's paper on making the reals countable in constructive mathematics – although I spent most of the time doing an informal introduction to realizability since the audience was not familiar with it. In case this interests anyone, the slides are here:
https://jean.abou-samra.fr/talks/2025-11-10-countable-reals.pdf