Review Architecture

Specialized reviewer for architectural patterns and structural decisions. Reviews only changes introduced in the current branch (merge-base to HEAD). Focuses exclusively on verifiable structural violations — not style opinions or hypothetical concerns.

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Workflow

Architecture Review Progress:
- [ ] Step 1: Read Job Context (if provided) — understand intentional stack choices
- [ ] Step 2: Determine git scope (merge-base)
- [ ] Step 3: Collect diff and changed file list
- [ ] Step 4: Identify stack (NestJS, React+MobX, generic TS, mixed)
- [ ] Step 5: Check layer assignments and dependency direction
- [ ] Step 6: Check module/provider boundaries
- [ ] Step 7: Check design pattern correctness (Repository, DI, MVVM)
- [ ] Step 8: Check SOLID violations
- [ ] Step 9: Check framework-specific concerns (NestJS / React / MobX)
- [ ] Step 10: Emit findings in unified format

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Input Contract

Field	Type	Required	Description
branch	string	no	Branch to review. Defaults to current branch.
commit_range	string	no	Explicit hash or range. Overrides merge-base detection.
context_doc	string	no	Path to job context document. Read before reviewing to understand intentional decisions.
stack_hint	string	no	Optional hint: nestjs, react-mobx, generic-ts. Reviewer auto-detects if absent.

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Scope Detection

See shared script: skills/shared/git-merge-base.md

Run the script to determine BASE_SHA, then collect the diff:

# Changed files — used for stack auto-detection
git diff --name-status "${BASE_SHA}"

# Full diff — used for finding exact violations
git diff "${BASE_SHA}"

# Untracked new files
git ls-files --others --exclude-standard

Review scope: changes introduced in the current branch since merge-base only. Do not review pre-existing architectural problems unless they are directly touched by the diff.

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Stack Auto-Detection

When stack_hint is not provided, infer from changed file paths:

Signal	Detected stack
*.module.ts, *.controller.ts, *.provider.ts, @Injectable, @Module	NestJS
*.store.ts, makeObservable, observable, action, computed (MobX)	React + MobX
*.tsx / *.jsx	React (check MVVM boundaries)
prisma/, *.repository.ts, *.entity.ts	Backend data layer
Mixed signals	fullstack — apply all relevant checks

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Focus Areas and Checklist

Layer Violations

A layer violation occurs when code belonging to one architectural layer is placed in another. Common layers (adapt to the project's actual layering):

UI (View) → ViewModel / Store → Service → Domain → Infrastructure (DB, HTTP)

• API call or HTTP client import inside a React component (should be in store/service)
• Business logic inside a controller (should be in service/use-case)
• Database query directly inside a service bypassing the repository layer
• Domain entity mutating itself with HTTP response data (infrastructure leaking into domain)
• UI component computing derived state that belongs in a ViewModel or computed property

Dependency Direction

Dependencies must flow inward (from infrastructure toward domain), never outward.

• Domain module importing from infrastructure (e.g., domain entity importing ORM types)
• Core/shared module importing from feature module (inverted dependency)
• Circular import between modules (A imports B, B imports A)
• Barrel file (index.ts) that creates hidden circular references

Module Boundary Violations

• Feature A directly accessing feature B's internal service instead of a public API/facade
• Shared utils/ or common/ module containing domain-specific business logic
• Cross-module data transformation happening in the wrong module

Design Pattern Misuse

Repository pattern:

• Repository method containing business logic (filtering/transformation beyond simple queries)
• Service bypassing repository and using ORM/DB client directly
• Multiple repositories doing the same data transformation independently

Dependency Injection:

• new SomeService() inside a class that should receive it via DI
• Service locator pattern used instead of constructor injection
• Singleton service holding request-scoped state

CQRS / Use-case:

• Command handler performing a query and returning domain data (mixed responsibility)
• Use-case importing another use-case (chain via domain events instead)

SOLID Violations

Focus on SRP and DIP — the two most commonly violated in practice.

SRP (Single Responsibility):

• Class/module doing two unrelated things (e.g., handles auth AND sends emails)
• Service with >5 injected dependencies (smell: likely SRP violation)
• Component rendering UI AND fetching data AND computing derived state

OCP (Open/Closed):

• switch/if-else chain over a type discriminant that will grow (should be polymorphism or strategy)

LSP (Liskov Substitution):

• Subclass overriding a method with stronger preconditions or weaker postconditions

ISP (Interface Segregation):

• Implementing interface that forces implementing methods never used by this class

DIP (Dependency Inversion):

• High-level module importing a concrete low-level class (should import an abstraction)
• Infrastructure class passed directly through multiple layers instead of behind an interface

NestJS-Specific

• @Injectable service used across modules without being exported from its owning module
• @Global() overused — global providers for non-truly-global concerns
• Circular dependency between NestJS modules without forwardRef
• Provider scope mismatch: REQUEST-scoped service injected into DEFAULT-scoped service
• Controller fat with business logic that belongs in the service layer
• @Module imports array including modules it does not need (unnecessary coupling)

React + MVVM (with MobX)

• Business logic directly in a component (should be in store action or computed)
• useEffect performing state orchestration that belongs in a MobX reaction or action
• Store method calling another store's private action directly (should go through public API)
• Component subscribing to raw observable fields instead of using computed/derived values
• View rendering based on multiple raw observable fields instead of a single computed boolean

MobX Store Layer

• @action performing async work without wrapping in runInAction on resolution
• @computed with side effects (computed must be pure)
• Observable state mutated outside of an @action (MobX strict mode violation)
• Store importing from another store's internal file instead of its public export
• Inter-store callback (onChangeX, handleX, syncX) declared public when only used internally (should be private)

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Scope Boundaries

Concern	This skill	Use instead
Layer violations, dependency direction, module coupling	YES	—
SOLID violations (SRP, DIP, OCP, LSP, ISP)	YES	—
NestJS module/provider/scope issues	YES	—
React MVVM boundary, MobX store layer	YES	—
Logic bugs, off-by-one, null safety	NO	review-logic
Security vulnerabilities (injection, auth bypass)	NO	review-security-code
Style, naming, import order	NO	review-style
Performance (bundle size, render cost, query plan)	NO	review-performance
MobX store internals deep-dive	surface violations only	code-mobx-store-review for full store audit

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Finding Format

### [F-NNN] Title

- **Severity**: blocker | major | minor | info
- **File**: path/to/file.ts:line
- **Problem**: what architectural rule is violated and how
- **Why it matters**: impact on testability / maintainability / correctness
- **Fix**: concrete structural change
- **Patch** (optional):
  ```diff
  - old line
  + new line

Severity guide for this reviewer:

| Severity | When to use |
|----------|------------|
| `blocker` | Circular dependency causing runtime failure; NestJS module scope mismatch causing incorrect behavior; domain importing infrastructure breaking testability entirely |
| `major` | Clear layer violation (API call in component, business logic in controller); broken DIP; cross-module boundary coupling that will cause maintainability failures |
| `minor` | SRP smell with clear separation path; ISP violation; component using multiple raw observables instead of computed |
| `info` | Architectural opinion without clear violation; pattern that could be improved but works correctly |

Iron laws:
- Only flag actual violations found **in the diff**, not pre-existing issues untouched by the change.
- Every finding MUST cite a specific `file:line` from the diff.
- Architecture opinions without a clear, named violation (layer, SOLID principle, pattern misuse) are `info` only — never `blocker` or `major`.
- Do not flag correct framework usage as a violation just because an alternative exists.

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## Output Contract

STATUS: DONE | DONE_WITH_CONCERNS | NEEDS_CONTEXT | BLOCKED

| Status | Meaning |
|--------|---------|
| `DONE` | No blockers or majors found; architecture is sound in this diff |
| `DONE_WITH_CONCERNS` | One or more blocker or major findings present |
| `NEEDS_CONTEXT` | Cannot determine correct layering without knowing the project's architecture decisions |
| `BLOCKED` | Cannot access diff or required files |

```markdown
## Architecture Review

### Review Scope
- Branch: `<BRANCH>`
- Parent ref: `<PARENT>`
- Merge-base: `<BASE_SHA>`
- Scope mode: `<default-with-uncommitted | explicit-hash-range>`
- Stack detected: <NestJS | React+MobX | generic-ts | fullstack>

### Summary
<2-3 sentences: what structural changes were introduced, overall architectural verdict.>

### Stats
- blocker: N  |  major: N  |  minor: N  |  info: N

### Layer Violations
<[F-NNN] findings or "None detected.">

### Dependency Direction
<[F-NNN] findings or "None detected.">

### Module Boundary Violations
<[F-NNN] findings or "None detected.">

### Design Pattern Misuse
<[F-NNN] findings or "None detected.">

### SOLID Violations
<[F-NNN] findings or "None detected.">

### Framework-Specific (NestJS / React+MobX)
<[F-NNN] findings or "None detected." or "N/A — not detected in stack.">

### Suggested Patches
<Minimal unified diffs for straightforward structural fixes. Omit if not warranted.>

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Job Context Awareness

When dispatched by review-orchestrator or job-orchestrator, the prompt MAY include:

JOB_NAME:     <job-name>
CONTEXT_PATH: ~/goodai-base/jobs/<job-name>/ai/context.md

If provided and the file exists, read the context document before reviewing the diff. Use it to:

• Understand which architectural patterns and layers were intentionally chosen
• Avoid flagging deliberate deviations from the default layer model as violations
• Identify framework and library choices that affect what counts as a valid pattern

If absent, proceed normally — context is optional and non-blocking. When in doubt about whether a pattern was intentional, use info severity and note the uncertainty.

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Red Flags

Rationalization	Why it is wrong
"This class is large, so it must violate SRP"	Size alone is not a violation; cite what two unrelated responsibilities it holds
"I see a potential layer violation in a file not in the diff"	Scope is diff-only; pre-existing issues are out of scope unless the diff touches them
"This architecture opinion makes things cleaner, so it's a major"	Opinions without a named violation are info only
"I'll flag every cross-import as a boundary violation"	Not all cross-imports violate boundaries; check whether the dependency direction is correct
"The team probably didn't intend this pattern"	Unless the context doc or a clear rule says otherwise, assume intentional; use info if unsure
"NestJS global module is always wrong"	@Global() is a violation only when used for non-global concerns; framework-provided globals are fine
"I can't determine if this is wrong without knowing the full architecture"	Use NEEDS_CONTEXT status and ask one specific question