# System Overview (docs/architecture/system-design.md)

Truth document. Use for: the bird's-eye view — what the system is, its subsystems, and how they connect. The first doc a new reader opens after the README; austere and short (two screens max). Depth lives in feature docs — this doc maps, it doesn't explain.

Required: **What this is**, **Subsystem map**. Optional: Key flows, Where the truth lives.

```
# System Overview

## What this is

{Two or three sentences: what the system does, for whom, in what environment it runs.}

## Subsystem map

┌──────────┐     ┌──────────┐     ┌──────────┐
│ Frontend │────▶│   API    │────▶│    DB    │
└──────────┘     └──────────┘     └──────────┘
{One box per subsystem; label the arrows with the contract that crosses them.}

- **{Subsystem}** — one line: what it owns. → [owning doc](../features/{feature}.md)

## Key flows

{At most two or three ASCII flow diagrams for the flows everything else hangs off — request lifecycle, auth, the core domain operation.}

## Where the truth lives

| Area | Canonical doc |
| ---- | ------------- |
| {area} | [{doc}](path) |
```