Stack
What I build with.
Not a shopping list. These are the tools and systems I actually use, why I picked them, and how they fit together.
AI & Development
I'm not a developer. I'm an operator who builds real things with AI. Claude Code is my IDE, my pair programmer, and my build system. Everything else is plumbing.
- Claude Code My primary development environment. Built this site from scratch, prototyped a retirement planner, run agentic workflows daily
- ChatGPT Conversational automation and the Telegram expense tracker integration
- Make.com & n8n Workflow orchestration. Voice-activated expense tracking via Telegram + Google Sheets
- Obsidian Knowledge vault for all Fortress21 research and operations
- Astro Powers this site. Static-first, fast, great DX
Security Stack
Security isn't a product you buy. It's something you build and maintain. Everything below works together. Pull one piece out and the whole setup changes. Reviewed quarterly against a custom threat model.
- YubiKey 5C NFC Hardware security keys for FIDO2/WebAuthn on every critical account
- Bitwarden Password management, self-hosted where possible
- ProtonMail Encrypted email for sensitive communications
- Recovery Architecture 2-of-3 geographically distributed recovery across Hong Kong and San Francisco
- 3-2-1 Data Backups Encrypted file and photo backups with geographic distribution
- Steel & Titanium Seed Backups 304 steel and titanium imprinted seed phrase backups
- Threat Model Custom threat model reviewed quarterly. Covers physical, digital, and social attack vectors
Bitcoin
Don't trust, verify. Every transaction goes through air-gapped hardware and my own node. Three hardware wallets in a multisig setup so there's no single point of failure.
- ColdCard Q Primary hardware wallet, air-gapped signing via microSD
- Keystone 3 Pro Secondary hardware wallet for multisig setups
- Blockstream Jade Plus Portable hardware wallet with camera for QR-based PSBT signing
- Sparrow Wallet Desktop coordinator for UTXO management, coin control, and multisig orchestration
- Own Node Full Bitcoin node. Block validation, mempool monitoring, privacy
Hardware
Apple Silicon runs everything. NAS storage split between Hong Kong and San Francisco for geographic redundancy.
- MacBook Pro 16" M3 The machine that runs everything
- Gigabyte M27Q External display for multi-window workflows
- 32TB NAS RAID 6 in San Francisco for encrypted backups
- NAS Redundancy (Planned) Secondary NAS for HK-SF cross-continental encrypted backup
Learning
Things move fast. I learn mostly by building, but these are the resources I keep going back to.
- Podcasts Modern Wisdom, Lex Fridman, The All-In Podcast
- Layered Money by Nik Bhatia
- Broken Money by Lyn Alden
Hobbies
Nothing to do with work. Just stuff I enjoy.