ISA-Frontend/docs/architecture/TEMPLATE.md

ADR NNNN:

Field	Value
Status	Draft / Under Review / Approved / Superseded by ADR NNNN / Deprecated
Date	YYYY-MM-DD
Owners	<author(s)>
Participants	<key reviewers / stakeholders>
Related ADRs	NNNN (title), NNNN (title)
Tags	architecture, ,

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Summary (Decision in One Sentence)

Concise statement of the architectural decision. Avoid rationale here—just the what.

Context & Problem Statement

Describe the background and the problem this decision addresses.

• Business drivers / user needs
• Technical constraints (performance, security, scalability, compliance, legacy, regulatory)
• Current pain points / gaps
• Measurable goals / success criteria (e.g. reduce build time by 30%)

Scope

What is in scope and explicitly out of scope for this decision.

Decision

State the decision clearly (active voice). Include high-level approach or pattern selection, not implementation detail.

Rationale

Why this option was selected:

• Alignment with strategic/technical direction
• Trade-offs considered
• Data, benchmarks, experiments, spikes
• Impact on developer experience / velocity
• Long-term maintainability & extensibility

Alternatives Considered

Alternative	Summary	Pros	Cons	Reason Not Chosen
Option A
Option B
Option C

Add deeper detail below if needed:

Option A –

Option B –

Option C –

Consequences

Positive

• …

Negative / Risks / Debt Introduced

• …

Neutral / Open Questions

• …

Implementation Plan

High-level rollout strategy. Break into phases if applicable.

1. Phase 0 – Spike / Validation
2. Phase 1 – Foundation / Infrastructure
3. Phase 2 – Incremental Adoption / Migration
4. Phase 3 – Hardening / Optimization
5. Phase 4 – Decommission Legacy

Tasks / Workstreams

• Infra / tooling changes
• Library additions (Nx generators, new libs under libs/<domain>)
• Refactors / migrations
• Testing strategy updates (Jest → Vitest, Signals adoption, etc.)
• Documentation & onboarding materials

Acceptance Criteria

List objective criteria to mark implementation complete.

Rollback Plan

How to revert safely if outcomes are negative.

Architectural Impact

Nx / Monorepo Layout

Describe changes to library boundaries, tags, dependency graph, affected projects.

Module / Library Design

New or modified public APIs (src/index.ts changes, path aliases additions to tsconfig.base.json).

State Management

Implications for Signals, NgRx, resource factories, persistence patterns (withStorage).

Runtime & Performance

Bundle size, lazy loading, code splitting, caching, SSR/hydration considerations.

Security & Compliance

AuthZ/AuthN, token handling, data residency, PII, secure storage.

Observability & Logging

Logging contexts (@isa/core/logging), metrics, tracing hooks.

DX / Tooling

Generators, lint rules, schematic updates, local dev flow.

Detailed Design Elements

(Optional deeper technical articulation.)

• Sequence diagrams / component diagrams
• Data flow / async flow
• Error handling strategy
• Concurrency / cancellation (e.g. rxMethod + switchMap usage)
• Abstractions & extension points

Code Examples

Before

// Previous approach (simplified)

After

// New approach (simplified)

Migration Snippet

// Example incremental migration pattern

Open Questions / Follow-Ups

• Unresolved design clarifications
• Dependent ADRs required
• External approvals needed

Decision Review & Revalidation

When and how this ADR will be re-evaluated (date, trigger conditions, metrics thresholds).

Status Log

Date	Change	Author
YYYY-MM-DD	Created (Draft)
YYYY-MM-DD	Approved
YYYY-MM-DD	Superseded by ADR NNNN

References

• Links to spike notes, benchmark results
• External articles, standards, RFCs
• Related code PRs / commits

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Document updates MUST reference this ADR number in commit messages: ADR-NNNN: prefix. Keep this document updated through all lifecycle stages.