Module Scaffolding Skill

This skill automates creation of new feature modules in the libs/ directory, following the project's conventions and patterns.

When to Use

• User asks to create a new feature/module
• User wants to add a new library to the monorepo
• User needs a new domain area (e.g., "authentication", "payments", "notifications")

Module Types

Type	Description	Includes
Full	Complete feature module	pages + routes + database + assets
Pages only	Web frontend only	pages + assets
API only	Backend API only	routes
Shared	Reusable code	business logic, no routes

Step-by-Step Instructions

Step 1: Gather Requirements

Ask the user for:

1. Module name (kebab-case, e.g., user-management)
2. Module type (full/pages/api/shared)
3. Whether it needs database models (yes/no)

Step 2: Create Directory Structure

# For full module:
mkdir -p libs/{name}/src/pages
mkdir -p libs/{name}/src/routes
mkdir -p libs/{name}/src/locales
mkdir -p libs/{name}/src/assets/css
mkdir -p libs/{name}/src/assets/js
mkdir -p libs/{name}/prisma

# For pages-only:
mkdir -p libs/{name}/src/pages
mkdir -p libs/{name}/src/locales
mkdir -p libs/{name}/src/assets/css

# For API-only:
mkdir -p libs/{name}/src/routes

# For shared library:
mkdir -p libs/{name}/src

Step 3: Generate Files

Use the templates in assets/ to create:

1. libs/{name}/package.json - from package.json.template

   • Replace {{MODULE_NAME}} with the kebab-case module name
   • Remove build:nunjucks script if no pages directory

2. libs/{name}/tsconfig.json - from tsconfig.json.template

   • No modifications needed

3. libs/{name}/src/config.ts - from config.ts.template

   • Remove unused exports based on module type:
     • No pages? Remove pageRoutes
     • No routes? Remove apiRoutes
     • No database? Remove prismaSchemas
     • No assets? Remove assets

4. libs/{name}/src/index.ts - from index.ts.template

   • Add business logic exports as they're created

5. libs/{name}/prisma/schema.prisma - from schema.prisma.template (if database needed)

   • Replace {{MODULE_NAME}} with module name
   • Replace {{ModelName}} with PascalCase model name (e.g., PaymentTransaction)
   • Replace {{table_name}} with snake_case table name (e.g., payment_transaction)

Step 4: Register Module

4a. Root tsconfig.json

Add to compilerOptions.paths:

"@hmcts/{name}": ["libs/{name}/src"]

4b. Web App (if module has pages)

In apps/web/src/app.ts, add import:

import { pageRoutes as {camelName}Pages } from "@hmcts/{name}/config";

Add to createSimpleRouter call or router setup.

4c. API App (if module has routes)

In apps/api/src/app.ts, add import:

import { apiRoutes as {camelName}Routes } from "@hmcts/{name}/config";

Add to createSimpleRouter call.

4d. Vite Config (if module has assets)

In apps/web/vite.config.ts, add import:

import { assets as {camelName}Assets } from "@hmcts/{name}/config";

Add to createBaseViteConfig array.

4e. Prisma Schema Discovery (if module has database)

In libs/postgres-prisma/src/schema-discovery.ts, add import:

import { prismaSchemas as {camelName}Schemas } from "@hmcts/{name}/config";

Add to schemaPaths array.

Step 5: Verify Setup

Run these commands to verify the module is set up correctly:

yarn                    # Install dependencies
yarn build              # Verify TypeScript compiles
yarn lint               # Check for lint errors

Naming Conventions

Element	Convention	Example
Module directory	kebab-case	libs/user-management/
Package name	@hmcts/{kebab}	@hmcts/user-management
Import alias	@hmcts/{kebab}	@hmcts/user-management
Config variable	camelCase + type	userManagementPages
File names	kebab-case	user-service.ts

Conversion Helper

kebab-case to camelCase for imports:

• user-management → userManagement
• council-tax → councilTax
• footer-pages → footerPages

Template Files

Templates are located in .claude/skills/module-scaffold/assets/:

• package.json.template - Package configuration
• tsconfig.json.template - TypeScript configuration
• config.ts.template - Module config exports
• index.ts.template - Business logic exports
• schema.prisma.template - Database model template (for modules with database)

Example: Full Module Creation

Creating a payment-gateway module:

1. Create directories:

   mkdir -p libs/payment-gateway/src/{pages,routes,locales,assets/css}
   mkdir -p libs/payment-gateway/prisma
   

2. Create package.json with name @hmcts/payment-gateway

3. Create tsconfig.json extending root

4. Create src/config.ts with all exports

5. Create src/index.ts placeholder

6. Create prisma/schema.prisma with model:

   model PaymentTransaction {
     id        String   @id @default(cuid())
     amount    Int
     status    String
     createdAt DateTime @default(now()) @map("created_at")
   
     @@map("payment_transaction")
   }
   

7. Register in tsconfig.json:

   "@hmcts/payment-gateway": ["libs/payment-gateway/src"]
   

8. Register in apps/web/src/app.ts:

   import { pageRoutes as paymentGatewayPages } from "@hmcts/payment-gateway/config";
   

9. Run verification:

   yarn && yarn build && yarn lint