Architecture decision records

Significant technical decisions are recorded as short ADRs: what was chosen, why, which alternatives were considered and what follows from it. Records are never edited after acceptance; a later ADR supersedes an earlier one.

Copy template.md for a new record. Number sequentially. Link the ADR from PROJECT_PLAN.md when the related decision in the decisions table is made.

Number	Title	Status
0001	Record architecture decisions	accepted
0002	Start from scratch, reuse AddaxAI Connect patterns	accepted
0003	PostgreSQL 17 with TimescaleDB and PostGIS from migration 1	accepted, confirmed at the phase 4 gate on 2026-09-03
0004	Redis Streams as the event bus	accepted
0005	Backend and frontend stack	accepted
0006	Schema versioning for bus messages, webhooks and API responses	accepted
0007	Canonical domain model	accepted
0008	Device timestamp deduplication	accepted
0009	Processing trace model	accepted
0010	Assignment attribution stored on canonical rows	accepted
0011	Connectivity adapter boundary	accepted
- 0012 rule representation
- 0013 control action schema
- 0014 integration deliveries are keyed on the object and retried from a table
- 0015 MCP security boundary
- 0016 backups and observability
- 0017 frames as deliveries, built-in channel sources, the browser as a route
- 0018 immutable source data and layered interpretation
- 0019 AI clients write through one policy-gated endpoint
- 0020 Entity groups as nested folders
- 0021 Firmware-aware device driver layouts
- 0022 The all-projects scope
- 0023 The satellite session behind an Iridium delivery
- 0024 Network health apart from device health, and the locations a network provides
- 0025 Entity types with sub-types and a standard catalogue
- 0026 One drawing engine for draw and measure, and a circle as a polygon that remembers its centre and radius
- 0027 The Gateways page shows a project's whole network, and the gateway list is synced daily
- 0028 The live map's feed, unread as a seen-up-to time per person, and a health dot slow to worry
- 0029 One top bar on every screen, and a night mode that reaches the map
- 0030 Roles as named permission sets, custom roles per project, and a member's scope enforced on every read
- 0031 Analysis as an isolated, optional subsystem
- 0032 Attribution repair as a background job with progress
- 0033 PDF reports of analyses made on the server
- 0034 Devices as analysis subjects, with levels
- 0035 Device settings known per device, from the type's catalogue
- 0036 Contacts as a canonical record type, and a place a device does not report
- 0037 Cardiac readings on the scanning device, with only what is published derived