# Architecture Decision Records

This directory holds the project's decision records — the "why" behind the
major technical choices. These were originally written during Phase 1 research
(dated Jan–Feb 2026) and moved here from the old `thoughts/research/` tree during
the documentation reconciliation. They are historical context, not current specs.

## Decisions

| Record | Topic |
|--------|-------|
| [tech-stack-decision.md](./tech-stack-decision.md) | Master stack choice: Rust/Axum backend, React frontend, MongoDB, JWT |
| [mongodb-schema-decision.md](./mongodb-schema-decision.md) | Document model + at-rest encryption approach |
| [jwt-authentication-decision.md](./jwt-authentication-decision.md) | JWT access/refresh tokens, recovery phrases |
| [frontend-decision-summary.md](./frontend-decision-summary.md) | React (web) + React Native (mobile, future) split |
| [state-management-decision.md](./state-management-decision.md) | Client state — *superseded*: decision was Redux Toolkit, **actual code uses Zustand** |
| [monorepo-structure.md](./monorepo-structure.md) | Repository layout (`backend/`, `web/`, `mobile/`, `docs/`) |
| [backend-deployment-constraints.md](./backend-deployment-constraints.md) | Deployment requirements (Solaria, Docker) |
| [mobile-health-frameworks-data.md](./mobile-health-frameworks-data.md) | HealthKit / Health Connect data-type reference (for future mobile work) |
| [android-health-connect-data-types.md](./android-health-connect-data-types.md) | Android Health Connect data types |

> **Note**: Where a decision diverges from the implemented code (e.g. state
> management), the code is the source of truth and the ADR is kept only as
> historical record of the reasoning at the time.