Style Guide (for Copilot Agent)¶

Core Development Rules¶

• Never invent files, folders, modules, APIs, types, or schema fields
• Always follow existing patterns in the repo
• Prefer modifying existing modules over creating new ones
• Backend-first workflow: Prisma schema → resolver → tests → frontend

TypeScript¶

• Strict mode required
• Never use any
• Explicit types for all variables, parameters, returns
• Use generated GraphQL types when available

Styling (React Native)¶

• Use NativeWind only (no web utilities like space-x, space-y, gap-*)
• Mobile-first, native components only
• Follow existing design tokens and patterns
• Reference docs/STYLE_GUIDELINES_TAILWIND.md for tokens
• Always follow docs/style_guideline.md for look & feel

Text / Localization¶

• All user-facing text must come from i18n.ts
• Create or update translation keys for new text
• Never hardcode UI strings

React Native (Expo)¶

• Functional components only
• Navigation: Expo Router
• State: Apollo Client (server), Zustand (UI/global)
• Use existing hooks/components before creating new ones

Backend (NestJS + GraphQL)¶

• Module structure: module/ → service.ts, resolver.ts, *.spec.ts
• Follow existing naming, decorators, and resolver patterns
• Prisma: Schema changes require pnpm -F backend run prisma:db:push
• Never add fields not defined in Prisma
• After backend changes: update GraphQL types via codegen

File Operations¶

• Always verify file/folder existence before referencing
• Use absolute paths when modifying files
• Read the file before making edits

Database¶

• MongoDB with Prisma
• Follow existing geospatial index patterns

ML¶

• Do not modify ML Python scripts unless inside apps/ml-training/
• TensorFlow Lite for on-device inference only

Security¶

• Use JWT auth patterns already present
• Never hardcode secrets or tokens

Testing¶

• Backend modules require unit tests
• GraphQL resolvers must include integration or e2e tests
• Maintain existing test structures

Last Updated: December 2025