The more journal peer review (JPR) became a scientific topic, the more it has been the subject of criticisms and controversies. Repeated fake reports, confirmed reviewers’ biases, lack of reproducibility, and a recurrent inability to detect fraud and misconduct have apparently condemned JPR in its supposedly traditional form. In fact, just like previous historical reforms and inventions, JPR has again been the object of many proposals to “fix it” since the beginning of the 21st century. Though these proposals are very diverse, two main directions have been identified: open peer review on one side, post-publication peer review (PPPR) on the other. These two “fixes” share a common device, the open commenting of published articles, which is both an open peer review practice as it is visible to all readers and PPPR as it comes after the publication and often the certification of articles. At their intersection, it should thus thrive and indeed many journals have proposed this feature, but with no success. Nevertheless, there is an exception to the disappointment with open commentary in PPPR, which is the empirical case for this presentation: PubPeer, where commentators come in herds and comments flourish. The only explanation given for this peculiar success is the possibility, largely used, to publish anoymized comments on the platform. So, how can you embrace the openness of discussion and, at the same time, enable anonymous commentators? What kind of PPPR practices is it connected with? Does it inform our views on traditional peer review and how? To answer these questions, we will first describe how the platform has been built and works, then to what kind of dynamics it leads as far as anonymity is concerned, then typify the arguments used for and against anonymity in PPPR, discuss its effects on published papers, before concluding on the way debates could be organized in PPPR. These first results are based on the systematic qualitative analysis of both threads on PubPeer, articles on specialized websites on PubPeer and anonymity (Scholarly Kitchen, RetractionWatch…) and on editorials from scientific journals that have commented on anonymity in PPPR.