Writing
Notes from shipping AI to production, and the infrastructure that makes it hold up.
Short, opinionated posts on the parts of AI engineering that don't get the keynote slot: evals, cost, latency budgets, refusal behavior, audit logs. Lately, also what blockchains do with the same problems: replay, finality, and irreversible commits. Mostly written with a musical on in the background. The opinions are mine; any typos are Hugh Jackman's fault.
- 7 min
A failed read is not an empty read
The most expensive two characters in my codebase were `?? []`. What I found when I chased one bug class across a dozen screens, why a source scan beat code review at catching it, and why it matters most in anything that shows you money.
systemsproductiontesting - 8 min
Turning a Solana transaction into a line in an activity feed
A wallet's history screen is a ledger projection of raw chain data. Why balance deltas beat instruction parsing as the source of truth, where classification gets hard, and how I'd test it with an eval set instead of vibes.
blockchainsolanaledger - 7 min
Finality for people who build ledgers
In Postgres, COMMIT is final. On a blockchain, a transaction becomes final in stages. Here's how I'd map Solana's and Ethereum's commitment levels onto ledger states, written from the reconciler side.
blockchainsolanaethereum - 7 min
Idempotency keys and nonces: replay protection from the payments side
I've spent years making retries harmless in payment and messaging pipelines. Ethereum and Solana solve the same problem with nonces and blockhashes, and the classic double-pay bug is the one I already know.
blockchainsolanaethereum - 8 min
Solana accounts vs. EVM storage, read as a database schema
Ethereum contracts own their storage and discover what they touch while running. Solana transactions declare every account up front, and that one rule explains its parallelism, its fee markets, and why a hot account is a hot row.
blockchainsolanaethereum - 7 min
What a wallet should show before you sign
Signing is the one irreversible step in a crypto transaction, and the confirmation screen is the last safety system in front of it. What simulation catches, what it can't, and the design rules I'd hold a signing flow to.
blockchainsecuritysolana - 8 min
I evaluated TigerBeetle for my ledger and shipped Postgres instead
FieldDay needs an append-only money ledger. The exciting answer was a dedicated financial database; the right answer was Postgres — until the throughput says otherwise. With the napkin math, the schema, and the u128 bug that nearly misrouted money.
fintechpostgressystems - 7 min
Shipping RAG to production: notes from building /ask
What I'd actually do — and what I'd skip — if you asked me to ship a retrieval-augmented agent for a small, well-defined corpus. With numbers from /ask on this site.
AIRAGproduction - 6 min
Evaluating LLM agents without going broke
A pragmatic playbook for evaluating LLM systems when you're one engineer with a portfolio budget and no patience for vibes-driven prompt tuning.
AIevalscost - 6 min
What a high-stakes marketing launch taught me about boring infrastructure
Idempotency keys, typed audit logs, dedup against a canonical record, backpressure, rehearsed failure. The unglamorous code that keeps a big launch quiet.
systemsinfraproduction