Location: backend/libs
config
Centralizes configuration loading and validation. It loads .env.<NODE_ENV>.local
first and falls back to .env, then exposes typed config via NestJS.
db
Prisma client and database access helpers. The Prisma schema lives in
backend/prisma/schema.prisma.
observability
Health checks and logging configuration shared by the API and worker.
contracts
Shared DTOs and contracts used across apps.