How do I install the Solid Java skill?

Run npx skillmds@latest add fusengine/solid-java-3 in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

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Is Solid Java free to use?

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Who published Solid Java?

fusengine (@fusengine) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Solid Java by fusengine — Agent Skill

Name: Solid Java
Rating: 4.666666666666667 (3 reviews)
Author: fusengine

File contents

SOLID Java - Modular Architecture

Agent Workflow (MANDATORY)

Before ANY implementation, use TeamCreate to spawn 3 agents:

fuse-ai-pilot:explore-codebase - Analyze existing architecture
fuse-ai-pilot:research-expert - Verify Java docs via Context7
fuse-ai-pilot:sniper - Post-implementation validation

DRY - Reuse Before Creating (MANDATORY)

Before writing ANY new code:

Grep the codebase for similar interfaces, services, or logic
Check shared locations: modules/core/services/, modules/core/interfaces/
If similar code exists -> extend/reuse instead of duplicate
If code will be used by 2+ features -> create it in modules/core/

Architecture (Modules MANDATORY)

Layer	Location	Max Lines
Controllers	`modules/[feature]/controllers/`	50
Services	`modules/[feature]/services/`	100
Repositories	`modules/[feature]/repositories/`	100
Interfaces	`modules/[feature]/interfaces/`	30
Models/DTOs	`modules/[feature]/models/`	50
Shared	`modules/core/{services,interfaces,models}/`	-

NEVER use flat src/ structure - always modules/[feature]/

Critical Rules (MANDATORY)

Rule	Value
File limit	100 lines (split at 90)
Controllers	< 50 lines, delegate to services
Interfaces	`modules/[feature]/interfaces/` ONLY
Javadoc	Every public method documented
Records	Use for DTOs (Java 16+)
Sealed	Use for restricted hierarchies (Java 17+)

Reference Guide

Concepts

Topic	Reference	When to consult
SOLID Overview	solid-principles.md	Quick reference
SRP	single-responsibility.md	Fat classes
OCP	open-closed.md	Adding providers
LSP	liskov-substitution.md	Contracts
ISP	interface-segregation.md	Fat interfaces
DIP	dependency-inversion.md	Injection
Architecture	architecture-patterns.md	Modular patterns

Templates

Template	When to use
module.md	Feature module structure
service.md	Business logic service
interface.md	Contract definition
repository.md	Data access layer
error.md	Custom exceptions
test.md	Unit tests with mocks

Forbidden

Anti-Pattern	Fix
Files > 100 lines	Split at 90
Interfaces in impl files	Move to `interfaces/` directory
`new ConcreteClass()` in services	Use dependency injection
Flat `src/` structure	Use `modules/[feature]/`
God classes	Split by responsibility

---name: solid-java-3description: SOLID principles for Java 21+. Files < 100 lines, interfaces separated, modular architecture. Modules MANDATORY.---# SOLID Java - Modular Architecture## Agent Workflow (MANDATORY)Before ANY implementation, use `TeamCreate` to spawn 3 agents:1. **fuse-ai-pilot:explore-codebase** - Analyze existing architecture2. **fuse-ai-pilot:research-expert** - Verify Java docs via Context73. **fuse-ai-pilot:sniper** - Post-implementation validation---## DRY - Reuse Before Creating (MANDATORY)**Before writing ANY new code:**1. **Grep the codebase** for similar interfaces, services, or logic2. Check shared locations: `modules/core/services/`, `modules/core/interfaces/`3. If similar code exists -> extend/reuse instead of duplicate4. If code will be used by 2+ features -> create it in `modules/core/`---## Architecture (Modules MANDATORY)| Layer | Location | Max Lines ||-------|----------|-----------|| Controllers | `modules/[feature]/controllers/` | 50 || Services | `modules/[feature]/services/` | 100 || Repositories | `modules/[feature]/repositories/` | 100 || Interfaces | `modules/[feature]/interfaces/` | 30 || Models/DTOs | `modules/[feature]/models/` | 50 || Shared | `modules/core/{services,interfaces,models}/` | - |**NEVER use flat `src/` structure - always `modules/[feature]/`**---## Critical Rules (MANDATORY)| Rule | Value ||------|-------|| File limit | 100 lines (split at 90) || Controllers | < 50 lines, delegate to services || Interfaces | `modules/[feature]/interfaces/` ONLY || Javadoc | Every public method documented || Records | Use for DTOs (Java 16+) || Sealed | Use for restricted hierarchies (Java 17+) |---## Reference Guide### Concepts| Topic | Reference | When to consult ||-------|-----------|-----------------|| **SOLID Overview** | [solid-principles.md](references/solid-principles.md) | Quick reference || **SRP** | [single-responsibility.md](references/single-responsibility.md) | Fat classes || **OCP** | [open-closed.md](references/open-closed.md) | Adding providers || **LSP** | [liskov-substitution.md](references/liskov-substitution.md) | Contracts || **ISP** | [interface-segregation.md](references/interface-segregation.md) | Fat interfaces || **DIP** | [dependency-inversion.md](references/dependency-inversion.md) | Injection || **Architecture** | [architecture-patterns.md](references/architecture-patterns.md) | Modular patterns |### Templates| Template | When to use ||----------|-------------|| [module.md](references/templates/module.md) | Feature module structure || [service.md](references/templates/service.md) | Business logic service || [interface.md](references/templates/interface.md) | Contract definition || [repository.md](references/templates/repository.md) | Data access layer || [error.md](references/templates/error.md) | Custom exceptions || [test.md](references/templates/test.md) | Unit tests with mocks |---## Forbidden| Anti-Pattern | Fix ||--------------|-----|| Files > 100 lines | Split at 90 || Interfaces in impl files | Move to `interfaces/` directory || `new ConcreteClass()` in services | Use dependency injection || Flat `src/` structure | Use `modules/[feature]/` || God classes | Split by responsibility |

Frequently asked questions

Solid Java