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+# Architecture Decision Records
+
+This folder contains lightweight ADRs (Architecture Decision Records) for the major design choices made during the initial design phase of the Blocao platform.
+
+## Conventions
+
+- Numbered sequentially: `0001-`, `0002-`, ...
+- Filename slug describes the decision in 3-5 words.
+- Status is one of: `proposed`, `accepted`, `superseded by NNNN`, `deprecated`.
+- ADRs are **never edited** after acceptance — superseding decisions get a new number.
+- Each ADR has: Context (why this came up), Decision (what we chose), Consequences (good and bad), Alternatives considered.
+
+## Index
+
+| # | Title | Status |
+|---|---|---|
+| [0001](0001-paleta-complementaria.md) | Complementary palette over classic LCARS | accepted |
+| [0002](0002-jerarquia-tiers.md) | Tier hierarchy: Router / Cell / Core / Hub | accepted |
+| [0003](0003-mqtt-como-espina-dorsal.md) | MQTT as the spine of the system | accepted |
+| [0004](0004-gitops-como-source-of-truth.md) | GitOps as the source of truth | accepted |
+| [0005](0005-sovereignty-vs-hyperscaler.md) | Sovereignty over hyperscaler convenience | accepted |
+| [0006](0006-router-sirve-shell-ui.md) | Router serves console shell, Cell provides APIs | accepted |
+| [0007](0007-evidence-chain-postpone.md) | Evidence chain is separate workstream, not blocking demo | accepted |
+| [0008](0008-retencion-30d-default-argentina.md) | Default 30-day retention for Argentina | accepted |
+| [0009](0009-no-redundancia-titulos.md) | No redundant titles in UI (rail + topbar + ctx-strip) | accepted |
+| [0010](0010-synopsis-como-landing.md) | SYNOPSIS as the landing view | accepted |
+
+## When to write a new ADR
+
+Write a new ADR whenever:
+
+- A choice between two or more reasonable alternatives is made and the choice will affect future work.
+- A decision is non-obvious enough that someone joining the project later will ask "why did they do it this way?".
+- The decision will be expensive to reverse.
+
+Don't write ADRs for trivial preferences (variable naming, file location, formatting). Those go in `docs/03-design/` if relevant.