01
Practical, tested code
Every snippet comes from a repository with a green suite behind it — unit tests in Vitest, integration in Mocha, end-to-end in Playwright. If it isn't tested, it doesn't get published.
typescript · architecture · testing · devops
Production-grade TypeScript, written down.
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100%Code under test
// domain depends on ports, never on infrastructure
export class CreateOrder {
constructor(
private readonly orders: OrderRepository,
private readonly clock: Clock,
) {}
async execute(cmd: CreateOrderCommand): Promise<Result<OrderId>> {
const order = Order.draft(cmd.customerId, this.clock.now());
for (const line of cmd.lines) {
const added = order.addLine(line);
if (added.isFailure()) return added;
}
await this.orders.save(order);
return Result.ok(order.id);
}
}
Stack covered
AWS
Playwright
AWS
Playwright
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Three things every article guarantees
02
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Not hello-world YAML. Multi-environment Kubernetes with Argo CD, progressive delivery, secrets handling, and the failure modes you only meet at 2am on a production cluster.
03
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Concrete ways to put agents to work inside a typed codebase: test-first prompting, refactor loops guarded by CI, and the review discipline that keeps generated code honest.
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about
Fifteen years of TypeScript, minus the hype
I'm Pat Francis. I build and maintain typed full-stack systems for a living — domain-heavy backends, boring reliable pipelines, front ends that don't fight their own types — and I write down what holds up under production load.
- Architecture-first: the shape of the code before the framework
- Opinionated, and clear about where the opinion ends
- Every article backed by a public, tested repository
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