Loop Handbooks

System handbooks for Loop's engineering systems — the doc a new engineer reads end to end before touching a system. One handbook per system, published as a single self-contained HTML page with a paged sidebar.

Live site: deployed on Vercel; each handbook lives at /docs/<system>/.

What a handbook is

Not an API reference and not a design doc — the operating manual between them. Every handbook follows the same skeleton (see the bundled skill):

1. Mental model — the system's nouns, as glossary tiles.
2. Tables & data model — schemas AND worked example rows from a real chain.
3. Vendor / dependency quirks — the facts that cost real hours.
4. Flows — reading vs changing, as diagrams; raw whiteboard sketches attach as click-to-open originals next to the redrawn version.
5. One-pass dry runs — the house diagram style: one real operation, the BEFORE tables, every mutation step naming the table it writes, the AFTER tables, with row-level diffs highlighted.
6. Deep dives — the state machines and edge cases, each rule annotated with the shipped bug it prevents.
7. Guard rails — the numbered never-break list.
8. API reference, runbooks, build history.

Add your handbook

1. Open this repo in Claude Code and run /system-handbook <your system> — the skill walks the structure above and produces docs/<system>/index.html.
2. Add a card for it in index.html.
3. PR to main; Vercel deploys on merge.

Authors

Created and maintained by Sanshray Langeh (@sansh72). First handbook: Self-serve Billing, Invoicing & Era History.