Deploy to Render: a one-click metrics pipeline, and the install telemetry it reports #331

@Ho1yShif, for your eyes: this is the plan for a one-click Deploy to Render button in this repository.

What

A Deploy to Render button in the README. One click creates:

• a Postgres,
• a pipeline that accepts metrics over a signed webhook and aggregates them by minute,
• an HTTP API that reads them back.

Render prompts for the HMAC secret during the deploy. Five minutes after the click, a user has sent a curl and queried its result.

The metric is generic: a name, a type (count or gauge), a value, free-form dimensions, and an optional timestamp. A minute stores sum, count, min, max and last, and a six-grain rollup ladder keeps 5m through 1d.

The same template reports two install events, install.deployed and install.first_request, to a collector we run. Telemetry is on by default, prompted for at deploy beside the secret, and the README prints both payloads. The collector is this same button deployed in our own workspace with signature validation switched off on purpose, so the template monitors itself.

Where it lives

render.yaml at the repository root, because Render's button reads it from there, and every other asset under /render.

Design

Specs and plans are in #330:

• docs/superpowers/specs/2026-09-18-render-metrics-template-design.md, the umbrella: scope, decisions, Blueprint, metric model, read API, auth, telemetry, build order.

Work

• Engine: source.webhook.addr. The webhook source listens on a constant, and Render assigns the port.
• Engine: sqlflow rollup gains numeric: double and a last measure. Every sum is cast to bigint today, which turns a gauge of 0.73 into 0.
• Engine: StructuredBatch corrupts a JSON object stored in a text column when a string inside it has an escape. Found while probing the template's dimensions.
• Release a tag with all three.
• The template: render.yaml and /render, with CI that brings it up, posts a signed metric, and reads it back at every grain.
• Deploy the collector from the template's PR branch. It is also the template's first real deploy.
• The telemetry client, its opt-out, and the README's "What this sends".

Open checks

• Whether the button honors a Blueprint in a subdirectory. Render documents only ?repo=.
• Whether Render needs a health route on the webhook service's public port. The pipeline answers /healthz on :8000, not on the webhook's port.