We are confident that Skimlinks does not affect SEO or Google PageRank.

Google's guidelines are clear that having affiliate links on your site is completely fine, as long as your site adds value, has original content and that the links are clearly relevant to the content.

We have always had a 'nofollow' within our redirect (only on monetizable links) as a further precaution.

You can refer to our blog post on the matter for some more comprehensive background.