Please scroll further. I understand that some of it is French but you should notice rather quickly nonetheless that this did not just happen on a single occasion. Essentially everything he writes fits into the narrative of #whitegenocide

I did dig in his tweets quite a lot, found many retweets of this pro-hitler account, also French extreme right parties, among normal right wing tweets. But all are retweets, no written ones, no debate, no long trolling. I also searched on google for mention of his nicks with hitler | holocaust | denier | ... and found nothing. If he did express disturbing views he did this on non indexed platforms.

I am surprised because I spent a lot of times on irc near lisp related (scheme, guile, emacs, so strictly speaking no CL, CLOS, lisp) channels and never heard bad mentions about him. Now I agree that this twitter account seems quite linked and probably pjb, but I can't decide anything based on just that.

His projects were removed from quicklisp in September (see e.g. http://blog.quicklisp.org/2016/09/september-2016-quicklisp-d...) over this matter.

That's a bit more telling. Are there any discussions on a mailing list ? or was is on irc and now lost ?

Please start with this log entry

> 2016-09-29T23:57:32Z Xach: I dropped com.informatimago because I do not want to have to discuss anything with pjb again. I have never enjoyed discussing anything previously, but his vile twitter feed drove me over the edge, and his project no longer builds, so I don't want to report problems or discuss solutions.

from here: http://ccl.clozure.com/irc-logs/lisp/lisp-2016-09.txt

on comp.lang.lisp he called the concentration camps 'a details in the history of WWII' and 'Then they killed in these camps less people than for example the International Socialists of the URSS and China, by two order of magnitudes!'

I see, classic French racist troll over historical statistics. Sad.