# Architecture

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A response to the spec, not a setting. Written AFTER concept, users,
requirements, NFR, IA, design system, interaction design, flows, and
mocks are in place. Major decisions get their own ADR; this file is the
summary + index.
-->

## Constraints (extracted from upstream artifacts)

- <constraint> — *from <source>.md*
- <constraint> — *from <source>.md*

## Stack at a glance

| Layer | Choice | ADR |
|---|---|---|
| Frontend | <…> | [ADR-NNNN](adr/NNNN-<slug>.md) |
| Backend | <…> | [ADR-NNNN](adr/NNNN-<slug>.md) |
| Data store | <…> | [ADR-NNNN](adr/NNNN-<slug>.md) |
| Hosting / runtime | <…> | [ADR-NNNN](adr/NNNN-<slug>.md) |
| Auth | <…> | [ADR-NNNN](adr/NNNN-<slug>.md) |
| Observability | <…> | [ADR-NNNN](adr/NNNN-<slug>.md) |

## Key architectural decisions

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One bullet per ADR with the heart of the decision. Full reasoning lives
in the ADR file.
-->

- **<Decision title>** — <one-line summary> ([ADR-NNNN](adr/NNNN-<slug>.md))

## Open questions

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Decisions deferred. Each should have a trigger condition that flips it
into a real ADR.
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- <question> — *will decide when <trigger>*