Hello,
I would like to bring to your attention an effort I stumbled across (of which I have not yet participated in), an attempt to identify the definitions and theorems from Rudin's "Principles of Mathematical Analysis" with their counterparts in Mizar: https://en.wikibooks.org/wiki/Mizar_Commentary_on_Walter_Rudin%27s_Principles_of_Mathematical_AnalysisNow, if only someone would do Dieudonne's treatise on analysis... ;)
Best,
Alex