# ADR-005: Database Selection — SQLite for Phase 1

**Status**: Accepted  
**Date**: 2026-04-05  
**Deciders**: Ezra (architect), Timmy Foundation  
**Scope**: Persistence layer for Conduit (#166, #183)

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## Context

Conduit supports SQLite and PostgreSQL. Synapse requires Postgres.

## Decision

Use **SQLite** for the initial deployment (Phase 1). Migrate to PostgreSQL only if user count or performance metrics trigger it.

## Consequences

| Positive | Negative |
|----------|----------|
| Zero additional container/service | Harder to scale horizontally |
| Single file backup/restore | Performance ceiling under heavy load |
| Conduit optimized for SQLite | |

## Migration Trigger

- Concurrent active users > 50
- Database file > 10 GB
- Noticeable query latency on room sync

## References

- Issue: [#166](http://143.198.27.163:3000/Timmy_Foundation/timmy-config/issues/166)
- Config: `infra/matrix/conduit.toml`