Engineering

Courier Skills: teach your AI agent to build with Courier

Courier Skills is a free, open-source knowledge base that teaches your AI coding agent how to build and debug notifications with Courier: the right primitive for each use case, the exact payload shapes, and the mistakes that produce unhelpful errors. The rebuilt version is smaller, leads every reference with the failure modes, and installs on any agent that reads skills with one command: `npx skills add trycourier/courier-skills`.

The federal texting rule your transportation and logistics software is breaking

A single text to a driving trucker can trigger a federal fine of up to $11,000 for the motor carrier, and your transportation and logistics software is often what sent it. How to design driver notifications that stay on the right side of FMCSA rules.

How Apple's on-device AI works, and what it changes for your users

Apple's 2026 on-device models (AFM 3) are good enough to read, rank, and summarize everything that lands on your phone, locally and for free. Here's how they actually work, in plain terms, and how a model that reads every message before your users do changes what you should send.

Apple Intelligence finally got smart. Here's how it changes the notifications your users see.

Apple Intelligence's on-device models got dramatically better in iOS 27, and they now summarize, rank, and filter notifications before your users ever see them. There's no API to control that, so the words you send are the only lever you have. Here's how notification summaries work and how to write for them.

The real cost of notifications at scale

The sticker price of a notification platform is never the real price. Cost scales with both message volume and user count, and the biggest expense is often the one nobody invoices: owning and running whatever you built yourself. Here's a clear way to model what notifications cost at scale and the levers that actually control it.

Email open tracking and consent: the new rules in Europe

Regulators in Europe are treating the email open-tracking pixel like a cookie, which means it needs consent before it fires. Here's what changed, who's actually in scope, what compliance requires, and how to keep sending while gating tracking on consent, including how to wire it up in Courier.

You can build anything now. That's exactly why you shouldn't build this.

AI made building software cheap, so the temptation is to build everything. But owning infrastructure is a permanent draw on your scarcest resource, attention. The value lives at two ends, the systems everything runs on and the product only you can make; the move is to build less, buy the opinionated platform, and let an agent operate it.

Email sender requirements: a developer's guide to the Gmail, Yahoo, and Outlook rules

Gmail, Yahoo, and Outlook have converged on one set of sender rules, and they've stopped being polite about enforcement. Here's what every developer sending email needs to have in place, provider by provider, plus where the rest of the market is heading.

I redid every cover image on our blog in an afternoon with Claude, Ideogram, and Contentful

I refreshed 81 blog covers, two years of posts, in a single afternoon. Claude Code orchestrated the pipeline, Ideogram generated the art, and the Contentful MCP moved every post in and out. Here is the stack, and why it only took an afternoon.