ADR-0007: Multi-tenant deployment topology

• Status: Accepted
• Date: 2026-07-25
• Deciders: El

Context

Multi-tenant isolation at two-person scale, without premature operational complexity.

Decision

Shared core stack (LangGraph, registry, Caddy, monitoring) built once; one Docker Compose stack per tenant (isolated Postgres + n8n) on per-tenant private Docker networks plus a shared-core network. Provisioned by Ansible. Docker Compose, not Kubernetes.

Consequences

Clean stand-up and tear-down per tenant; isolation is the container and network boundary; infra cost scales roughly linearly with tenants; no orchestration platform to operate.

Alternatives considered

• Kubernetes — rejected: premature complexity at this scale.
• Shared everything with tenant_id rows — rejected: weaker isolation than the container boundary.