A profile page at github.io, kept for historical reasons
In 2017 every GitHub account ended up with a <username>.github.io repository, because GitHub Pages was the default static-hosting option and the URL was right there in the username. Mine got set up the same day I created the account. The contents have not meaningfully changed since.
This is one of those repositories that I keep because deleting it would be lying. The account has been doing what it's been doing — cryptography, distributed systems, the occasional FPGA project, the occasional bitcoin-adjacent research — since 2017 at least. The GitHub Pages site is the proof of that, in URL form, with a creation date that's auditable.
The site itself is a single HTML page with a couple of dozen kilobytes of content and no JavaScript. The README is one line: a link to the site. The site exists because in 2017 having a personal landing page on github.io was a low-cost way to assert "I am a person on the internet and here is where my code lives." That was the entire premise.
Now I have zkdefi.com for the LinkedIn-styled resume, zkdefi.org for the Forgejo mirror of everything, and blog.zkdefi.org for the post you're reading. The github.io site is redundant. It also predates all of those by close to a decade, so it stays.
It's worth saying that the practice of having an opinionated landing page has gotten harder as the substrate around it has gotten more contested. GitHub Pages in 2017 was simple — one repo, one branch named master, one index.html. Now you have to decide between GitHub Pages and your own domain, between a static generator and a CMS, between hosting locally and hosting on a cloud you've audited, between rendering a static page and shipping a SPA. None of those choices is wrong. All of them require a commitment that the 2017 me didn't have to make.
The 2017 page sits at https://saymrwulf.github.io and accomplishes one thing: the URL works. Click on a link to my GitHub profile from any document I authored in the late 2010s, and the click resolves. That's its whole job. It does it.
What becomes possible: the longest-living single artifact in the account, kept honestly, with no makeover applied to disguise its age.