I draw the boxes,then I have to build them.
Most architecture goes wrong at the handoff. Someone diagrams a system they will never operate, and someone else discovers the diagram was a wish. I do both halves, which is a slower way to work and a much harder one to fake.
Fourteen years in: five inside product companies, nine freelance. Payments ledgers, vessel telemetry, multi-tenant platforms, and a fair number of monoliths taken apart without a feature freeze. The engagements are short by design — six weeks to eleven months — because my job is to leave a system the resident team can run and extend without me.
Before this I spent three years on an on-call rotation for a system I had designed badly. That is where most of the opinions below come from.
01
The architect stays on the rotation
A design you never have to operate is a hypothesis. I stay through the first production quarter, which changes what I am willing to draw.
02
Migrations ship in increments or not at all
No big-bang weekends and no feature freezes. Dual-write, shadow-compare, cut over on a config flag. If a step cannot be reversed by Tuesday, it is too big.
03
Read the incident log first
Two weeks of your postmortems and your on-call channel tell me more than any architecture review. The real system is the one that pages people.
04
Boring technology, deliberately chosen
Postgres until it hurts, then a considered exception with a written reason. Novelty is a budget: spend it on the one thing that is genuinely hard for you.
05
The handover is the deliverable
Runbooks, a load-test harness, and two engineers who can whiteboard the design without me. An engagement that ends in dependency has failed.
2017 — 2022
Staff engineer, then principal — logistics marketplace
Owned the ledger and settlement domain through 40× volume growth. Learned what a bad boundary costs at four in the morning.
2014 — 2017
Backend engineer — payments processor
Card processing and reconciliation. Where the double-entry habit came from, and the distrust of floating point.
2012 — 2014
Developer — agency, Nairobi
Thirty projects in two years. An excellent education in what a deadline does to a design.
Nairobi, Kenya. GMT+3, overlapping most of the European working day, with afternoons reaching US East mornings.
English, Filipino. Diagrams, when neither is working.
Got a system that needsdesigning properly this time?
Contracts from six weeks. I read every enquiry myself and reply within two working days, usually with an awkward question about your data model.