John Daniel Kearney

I am John. I live in San Francisco and I make things, mostly hardware and cryptography, usually at home, usually because I wanted to find out whether the thing was possible at all.

Most of what is here started as a question I could not look up. What is actually inside this chip. Can a chain do something useful with the work it burns. Can you stage sleep with a hundred dollars of parts. The projects are the answers, in the state the answers were left in.

jOhNCHAIN

A blockchain I wrote in Rust from scratch. It has been running on a box in a datacentre since July, unattended, making a new block every fifteen seconds. Instead of burning the work on hashes that mean nothing, every block tries to breed a better AES-style S-box, so the chain spends its life doing cryptanalysis.

There is no server behind the pages below. They are the chain.

• Block explorer, watch it tick
• The evolver, S-box scores as they improve
• Sign the guestbook, the hit counter runs off the block height
• A website with no server, the page HTML lives in chain state

Everything else

Where a thing is public it is a link. Where it is not, it is still real, it just does not have a page yet.

• rt-silicon, opening up chips to see what is actually in them. 36 verified findings so far.
• openeeg-mask, sleep staging out of $128 of parts, because the commercial ones would not show me the raw signal.
• Culture, a pomodoro timer made of mould. It grows while you work and dies if you do not.
• Mycoschism, shaders and renders. Things that draw themselves.
• ClipForge, video from a single seed, generated offline, no model in the loop.
• Agentic Arena, tournaments settled on chain.
• PyGrind, Python drills with an ELO rating, so the problems fight back.
• FlipFlow, a timer you can run backwards.