solid-react v1.0.0A

Immutable. This exact content never changes and is served at /api/v1/blob/b7667b0b339658b3.

---
name: solid-react
description: Use when applying SOLID principles to React architecture — file-size limits, hook separation, src/interfaces/, JSDoc.
version: 1.0.0
user-invocable: true
references: references/solid-principles.md, references/single-responsibility.md, references/open-closed.md, references/liskov-substitution.md, references/interface-segregation.md, references/dependency-inversion.md, references/architecture-patterns.md, references/templates/component.md, references/templates/hook.md, references/templates/service.md, references/templates/store.md, references/templates/interface.md, references/templates/validator.md, references/templates/factory.md, references/templates/adapter.md, references/templates/error.md, references/templates/test.md
---

<objective>
Enforces SOLID and DRY architecture on React 19 projects: source files within `FUSE_SOLID_MAX_LINES` and split by responsibility when cohesion drops, types isolated in `modules/[feature]/src/interfaces/` (never in component files), mandatory JSDoc on exports, no class components, and mandatory grepping for existing logic/utilities before writing new code (with `jscpd` duplication checks).

Provides a dedicated reference guide per SOLID letter (SRP file-splitting, OCP composition/render-props, LSP contract compliance, ISP role-based props/context, DIP constructor injection via Context) plus 10 ready-to-copy templates covering components, hooks, services, stores, validators, factories, and tests. This is a cross-cutting code-quality skill, not a feature skill — for the React APIs themselves see react-19, react-state, react-forms, and react-tanstack-router.
</objective>

# SOLID React - Component Architecture

## Codebase Analysis (MANDATORY)

**Before ANY implementation:**
1. Explore project structure to understand architecture
2. Read existing related files to follow established patterns
3. Identify naming conventions, coding style, and patterns used
4. Understand data flow and dependencies

## DRY - Reuse or Create Shared (MANDATORY)

**Before writing ANY new code:**
1. **Grep the codebase** for similar function names, patterns, or logic
2. Check shared locations: `modules/cores/lib/`, `modules/cores/components/`, `modules/cores/hooks/`
3. If similar code exists → extend/reuse instead of duplicate
4. If code will be used by 2+ features → create it in `modules/cores/` directly
5. Extract repeated logic (3+ occurrences) into shared helpers
6. Run `npx jscpd ./src --threshold 3` after creating new files

---

## Agent Workflow (MANDATORY)

Before ANY implementation, spawn 3 agents in parallel, one `Agent` call each with a `name`:

1. **fuse-ai-pilot:explore-codebase** - Analyze project structure and existing patterns
2. **fuse-ai-pilot:research-expert** - Verify latest docs for all stack technologies
3. **mcp__context7__query-docs** - Check integration compatibility

After implementation, run **fuse-ai-pilot:sniper** for validation.

---

## Absolute Rules (MANDATORY)

### 1. Source-file size ceiling

- Source files must not exceed `FUSE_SOLID_MAX_LINES` - the hook's ceiling is the only authority
- Split by responsibility when cohesion drops (components via composition, hooks, services)

### 2. Modular Architecture

See `references/architecture-patterns.md` for complete structure with feature modules and cores directory.

### 3. JSDoc Mandatory

```typescript
/**
 * Fetch user by ID from API.
 *
 * @param id - User unique identifier
 * @returns User object or null if not found
 */
export async function getUserById(id: string): Promise<User | null>
```

### 4. Interfaces Separated

```text
modules/[feature]/src/interfaces/
├── user.interface.ts
├── post.interface.ts
└── api.interface.ts
```

**NEVER put interfaces in component files.**

---

## SOLID Principles (Detailed Guides)

Each SOLID principle has a dedicated reference guide:

1. **`references/single-responsibility.md`** - One function = one reason to change
   - Responsibility-based splitting within `FUSE_SOLID_MAX_LINES`
   - Component composition patterns
   - Split strategy

2. **`references/open-closed.md`** - Extend via composition, not modification
   - Plugin architecture patterns
   - Render props and slots
   - Strategy patterns

3. **`references/liskov-substitution.md`** - Contract compliance & behavioral subtyping
   - Interface contracts
   - Swappable implementations
   - Testing compliance

4. **`references/interface-segregation.md`** - Many focused interfaces beat one fat interface
   - Role-based interfaces
   - Props segregation
   - Context splitting

5. **`references/dependency-inversion.md`** - Depend on abstractions, not implementations
   - Constructor injection patterns
   - Factory patterns
   - Context for DI

See `references/solid-principles.md` for overview and quick reference.

---

## Code Templates

Ready-to-copy code in `references/templates/`:

| Template | Usage |
|----------|-------|
| `component.md` | React functional component |
| `hook.md` | Custom hook with TanStack Query |
| `service.md` | Service with dependency injection |
| `store.md` | Zustand store with persistence (max 40 lines, owner rule) |
| `interface.md` | TypeScript interfaces |
| `validator.md` | Zod validation schemas |
| `factory.md` | Factory pattern |
| `adapter.md` | Adapter pattern |
| `error.md` | Custom error classes |
| `test.md` | Vitest + Testing Library |

Every template stays within `FUSE_SOLID_MAX_LINES`.

---

## Response Guidelines

1. **Research first** - MANDATORY: Search Context7 + Exa before ANY code
2. **Show complete code** - Working examples, not snippets
3. **Explain decisions** - Why this pattern over alternatives
4. **Include tests** - Always suggest test cases
5. **Handle errors** - Never ignore, use error boundaries
6. **Type everything** - Full TypeScript, no `any`
7. **Document code** - JSDoc for complex functions

---

## Forbidden

- Coding without researching docs first (ALWAYS research)
- Using outdated APIs without checking current year docs
- Source files exceeding `FUSE_SOLID_MAX_LINES`
- Interfaces in component files
- Business logic in components
- Class components
- Missing JSDoc on exports
- `any` type
- Barrel exports (index.ts re-exports)
- `useEffect` for data fetching (use TanStack Query or Router loaders)
- Module importing another module (except cores)
- Duplicating existing utility/helper without Grep search first
- Copy-pasting logic blocks instead of extracting shared function