A letter that keeps its own secret
How Sparrow protects webhook credentials with envelope encryption. A database backup turns up somewhere it should not be, so we open it and see what a stranger would find.
Field notes
Small promises, kept carefully.
A webhook is a promise: when this happens, I will tell you. These are notes on what it takes to keep that promise, and on the people at either end of it.
Describe the payload, get the template
Draft a subscription's transform template from a plain-language description, verified by rendering and repaired until it works, with Anthropic, any OpenAI-compatible server, or a copy-and-paste prompt.
Speak the receiver's language
Why Sparrow uses Go templates for subscription transformations instead of embedding JavaScript, and what a small, restrained language buys you on the delivery path.
Write it down once
How Sparrow recipes turn webhooks into integrations for Slack, PagerDuty, ClickHouse and more. The first integration is a favour; by the third, you want to write it down.
Keep the record close
Why Sparrow is self-hosted first. A partner's endpoint goes dark overnight, and the next morning the only thing that matters is whether you can say what they missed.
Knowing when to knock again
How Sparrow classifies webhook delivery failures. A timeout, a 401 and a 503 look alike on a dashboard, but each one asks for a different response.