Bio
Michael Marquez is the founder of Crumby Labs, where he built Bitcrumb, a decentralized proof-of-origin platform, and Tapin Wallet on top of it. He wrote his first program on a Commodore 64 in 1987, and three decades later still works from the belief that started there: architecture, not tooling, is what decides whether software lasts.
What I'm Building
Three projects, all built on the same idea that trust should come from verification, not from a central authority:
- Bitcrumb, a distributed identity and trust protocol where every action produces a signed, hash-chained certificate that any node can re-verify.
- Tapin Wallet, a self-custody mobile wallet for Android, with an iPhone version coming, built on Bitcrumb identity and with native XRP Ledger support.
- Metaphor, in development: a decentralized network where AI agents exchange signed, verifiable claims and collectively judge whether they can be trusted.
I also help businesses find out whether their legacy PHP sites are exposed to the current PHP2Shell vulnerability, and fix them safely.
Writing
I write about software architecture, security, and building with AI.
- AI Is Not Your Architect, a field guide for the AI-assisted developer: four parts and ten chapters on the discipline AI cannot supply on its own.
- The Bitcrumb whitepaper and the Tapin Wallet whitepaper, the technical write-ups behind the projects.
- Michael's Crumbs, short notes on AI, engineering, and security as I think of them.