Lays down the append-only audit log: schema, migration with role grants, NestJS AuditWriter service. Typed event-family methods, separate AUDIT_DATABASE_URL pool, retention job, and live-DB integration tests are explicitly listed as "wired as features land" in ADR-0013 §Confirmation. Schema (apps/portal-bff/prisma/schema.prisma): - multiSchema preview enabled; datasource declares public + audit schemas. - AuditEvent model with: id (uuid), createdAt, eventType (free-form in v1, will formalise into a catalogue once we have N stable types), audience (workforce|customer enum), actorIdHash, traceId, subject, outcome (success|failure|denied enum), payload (jsonb). - Indexes on createdAt, eventType, traceId — covering the obvious query shapes (date-range scan, by event family, by trace for log-audit correlation). Migration (prisma/migrations/*_init_audit_schema/migration.sql): - CREATE TABLE / enums via Prisma's standard output. - Append-only contract re-applied explicitly: ALTER TABLE / TYPE OWNER TO audit_owner, then GRANT INSERT to audit_writer, SELECT to audit_reader, SELECT+DELETE to audit_archiver. SELECT is required for archiver because Postgres needs SELECT on every column referenced in DELETE's WHERE clause to evaluate "older than retention" — granted explicitly in this PR rather than silently failing later. - USAGE on the enum types granted to all three roles so audit_ writer's INSERT does not fail with "permission denied for type". - No GRANT for UPDATE / TRUNCATE to anyone, including audit_owner at runtime — only fresh schema migrations amend the table. Service (apps/portal-bff/src/audit/): - AuditWriter.recordEvent(input) — single entry point. Wraps every INSERT in a transaction whose first statement is `SET LOCAL ROLE audit_writer`, so the role contract holds at runtime even from the otherwise-privileged BFF connection. SET LOCAL is reset on COMMIT/ROLLBACK so the pool's next consumer sees the original role. - traceId auto-resolved from the active OTel span context. - actorIdHash auto-resolved from CLS (key 'actorIdHash') with explicit input-side override; null when neither is set (placeholder until ADR-0009 / ADR-0010 guards populate CLS). - Errors propagate (no catch-and-swallow), per ADR-0013's "blocking writes: no audit ⇒ no action". - AuditModule exposes the writer; wired into AppModule so any future feature module can inject it. Tests (apps/portal-bff/src/audit/audit.service.spec.ts, 8 cases): - Locks the transaction to audit_writer before INSERTing. - Passes input fields through. - Records Prisma.JsonNull when no payload is provided. - Reads actorIdHash from CLS when not passed. - Prefers explicit actorIdHash over CLS-resolved. - Stores actorIdHash = null when neither input nor CLS has one. - Captures the active OTel trace id. - Stores traceId = null when no span is active. - Propagates the underlying error (no swallow). End-to-end smoke against local-dev Postgres (manual, via psql): - INSERT under audit_writer: ok. - UPDATE under audit_writer: "permission denied for table events". - DELETE under audit_writer: "permission denied for table events". - DELETE under audit_archiver (after the SELECT grant fix): ok, row removed. ADR-0013 §Confirmation rewritten as "wired in foundation PR" / "wired as features land", with the latter listing the typed event-family methods, AUDIT_DATABASE_URL split, startup self-test probe, retention purge job, salt-shared cross-correlation test, and live-DB role-contract integration tests.
Architectural Decision Records
This project records architecturally-significant decisions as ADRs in the MADR 4.0.0 format. References: adr.github.io.
Why ADRs
ADRs capture the why behind a decision — context, drivers, options considered, trade-offs accepted — at the moment the decision is made. They make architecture reviewable, onboarding faster, and prevent the same debate from being re-litigated later.
Conventions
- Format: MADR 4.0.0. Start from template.md.
- Filename:
NNNN-kebab-case-title.md, e.g.0007-adopt-tailwind-for-design-tokens.md. - Numbering: globally sequential 4-digit prefix. Numbers never reset, never get reused — even when an ADR is superseded or deprecated.
- Layout: flat folder. ADRs are not nested into category subfolders; topical organization happens via tags.
- Tags: every ADR carries a
tags:array in the MADR frontmatter, drawn from the tag vocabulary below. An ADR may carry several tags. Propose new tags (or renames) in the same PR that needs them; never invent ad-hoc tags inline. - Status lifecycle:
proposed→accepted→ optionallydeprecatedorsuperseded by [ADR-NNNN](NNNN-other.md). Update the YAML frontmatter; never delete an ADR. - Index maintenance: every ADR addition or status change must update the Index below in the same commit.
When to write an ADR
Write one whenever a development decision is non-trivial: tool or library choice, framework pattern, security control, perf budget, a11y target, naming convention, deprecation, breaking change, or any choice that future contributors would benefit from understanding the why of.
Tag vocabulary
The vocabulary below is the source of truth. It is intentionally coarse — propose extensions only when an existing tag genuinely doesn't fit, and avoid overly narrow tags.
| Tag | Scope |
|---|---|
frontend |
UI, Angular, components, design system, client-side state |
backend |
API, BFF, server-side services |
security |
AuthN, AuthZ, sessions, CSP, dependency scanning, secret management |
performance |
Perf budgets, caching, bundle size, Lighthouse |
accessibility |
WCAG, a11y testing, keyboard, ARIA, contrast |
infrastructure |
CI/CD, hosting, deployment, runtime |
observability |
Logs, metrics, traces, correlation IDs, monitoring |
data |
Persistence, schemas, migrations, data flow |
process |
Team conventions, workflows, repo policy |
Status: starter vocabulary, to be refined as ADRs accumulate. Update this table whenever a tag is added, renamed, or retired.
Index
ADRs are listed in numerical order. To slice by topic, filter on the Tags column.
| # | Title | Status | Tags | Date |
|---|---|---|---|---|
| 0001 | Use ADRs to record architectural decisions | accepted | process |
2026-04-29 |
| 0002 | Adopt Nx monorepo with the apps preset |
accepted | infrastructure, frontend, backend |
2026-04-29 |
| 0003 | Workspace and app naming convention | accepted | process |
2026-04-29 |
| 0004 | Frontend stack — Angular (latest LTS), standalone, zoneless, Signals, CSR-only, Vitest | accepted | frontend |
2026-04-29 |
| 0005 | Backend stack — NestJS over Express, Fastify, Hono | accepted | backend |
2026-04-29 |
| 0006 | Persistence — PostgreSQL with Prisma | accepted | data, backend |
2026-04-29 |
| 0007 | Pre-commit hooks and Conventional Commits | accepted | process |
2026-04-29 |
| 0008 | Identity model — multi-tenant Entra ID for workforce, dual-audience design for future External ID | accepted | security, data |
2026-04-29 |
| 0009 | Authentication flow — OIDC Authorization Code + PKCE via MSAL Node, BFF session pattern | accepted | security, backend |
2026-04-29 |
| 0010 | Session management — opaque session IDs in cookies, payload in self-hosted Redis with AES-GCM at rest | accepted | security, backend, infrastructure |
2026-04-29 |
| 0011 | MFA enforcement — Entra ID Conditional Access baseline, BFF claim sanity-check, step-up hooks designed-in | accepted | security |
2026-04-29 |
| 0012 | Observability — Pino structured logs + OpenTelemetry tracing, W3C Trace Context propagation, stdout + collector | accepted | observability, backend, frontend |
2026-04-29 |
| 0013 | Audit trail — separated append-only Postgres schema, decoupled from app logs | accepted | security, observability, data |
2026-04-29 |
| 0014 | Downstream API access — On-Behalf-Of pattern, unified DownstreamApiClient, audience-aware authorization |
accepted | security, backend |
2026-04-29 |
| 0015 | CI/CD pipeline — Gitea Actions, trunk-based + squash-merge, thin YAML over portable scripts | accepted | infrastructure, process |
2026-04-30 |
| 0016 | Accessibility baseline — WCAG 2.2 AA + targeted AAA, Angular CDK + spartan-ng + Tailwind, APF panel testing | accepted | accessibility, frontend, process |
2026-04-30 |
| 0017 | Performance budgets — Core Web Vitals + Lighthouse CI gates, bundle budgets, BFF p95/p99 SLOs | accepted | performance, frontend, backend, process |
2026-04-30 |