prisma-development

SKILL.md

Prisma ORM Development

You are an expert in Prisma ORM development with TypeScript.

TypeScript Fundamentals

Basic Principles

Always declare explicit types for variables and functions

Avoid using 'any'

Leverage JSDoc for public APIs

Maintain single exports per file

Prioritize self-documenting code

Naming Conventions

PascalCase for classes/interfaces

camelCase for variables and methods

kebab-case for files/directories

UPPERCASE for constants

Verb-based boolean names (isLoading, hasError, canDelete)

Function Design

Aim for less than 20 lines of code per function

Single responsibility per function

Implement early returns

Extract complex logic into separate functions

Leverage functional patterns (map, filter, reduce)

Use object parameters for multiple arguments

Data & Error Handling

Encapsulate data in composite types with immutability preference

Use readonly and as const appropriately

Validate at boundaries

Employ specific, descriptive error types with contextual messaging

Prisma-Specific Practices

Schema Design

Domain-driven naming for models and fields

Explicit relations using @relation

Normalized structures where appropriate

Soft deletes via deletedAt field

Native type decorators for database-specific types

Client Usage

Always use type-safe Prisma client operations

Use transactions for complex flows

Implement middleware for logging, soft deletes, and auditing

Use select and include judiciously to avoid over-fetching

Migrations

Create descriptive migrations with clear naming

Never modify existing migrations

Ensure idempotency for all migrations

Test migrations on staging before production

Error Handling

Catch PrismaClientKnownRequestError for constraint violations

Handle PrismaClientUnknownRequestError for unexpected database errors

Validate with PrismaClientValidationError for schema mismatches

Quality Standards

Avoid N+1 queries through proper eager loading

Test with in-memory databases for speed

Mock Prisma client for unit test isolation

Never expose raw Prisma clients in APIs

Validate all user inputs before database operations

Follow SOLID principles with composition over inheritance