Backend folder structure

├── scripts
├── e2e-test
├── bdd
└── src/
    ├── @types/
    │   ├── knex.d.ts
    │   ├── fastify.d.ts
    │   ├── ...
    ├── db/
    │   ├── migrations
    │   ├── schemas
    │   └── seeds
    ├── keystore/
    ├── lib/
    │   ├── api-docs
    │   ├── aws
    │   ├── axios
    │   ├── base64
    │   ├── casl
    │   ├── certificates
    │   ├── config
    │   ├── crypto
    │   ├── dates
    │   ├── delay
    │   ├── error-codes
    │   ├── errors
    │   ├── files
    │   ├── fn
    │   ├── ...
    ├── queue
    ├── server/
    │   ├── routes/
    │   │   ├── v1
    │   │   ├── v2
    │   │   ├── v3
    │   │   └── v4
    │   ├── plugins
    │   ├── config
    │   └── lib
    ├── services/
    │   ├── auth
    │   ├── org
    │   ├── ...
    │   └── project/
    │       ├── project-service.ts
    │       ├── project-types.ts
    │       └── project-dal.ts
    └── ee/
        ├── routes
        └── services

backend/scripts

Contains reusable scripts for backend automation, like running migrations and generating SQL schemas.

backend/e2e-test

Integration tests for the APIs.

backend/bdd

Behavior-Driven Development (BDD) tests using Python and Gherkin feature files.

backend/src

The source code of the backend.

• @types: Type definitions for libraries like Fastify, Knex, and other third-party dependencies.
• db: Knex.js configuration for the database, including migrations, seed files, and SQL type schemas.
• keystore: Key-value store abstraction layer supporting Redis and PostgreSQL for application caching, distributed locking, and coordination.
• lib: Stateless, reusable functions used across the codebase, organized by functionality (crypto, config, dates, etc.).
• queue: Infisical's queue system based on BullMQ.

src/server

• Scope anything related to Fastify/service here.
• Includes routes, Fastify plugins, server configurations, and server-specific utilities.
• The routes folder contains various versions of routes separated into v1, v2, v3, v4, etc.

src/services

• Handles the core business logic for all operations.

• Follows the co-location principle: related components should be kept together.

• Each service component typically contains:

  1. dal: Database Access Layer functions for database operations
  2. service: The service layer containing business logic.
  3. type: Type definitions used within the service component.
  4. fns: An optional component for sharing reusable functions related to the service.
  5. queue: An optional component for queue-specific logic, like secret-queue.ts.

src/ee

Follows the same pattern as above, with the exception of a license change from MIT to Infisical Proprietary License.

Guidelines and Best Practices

• All services are interconnected at /src/server/routes/index.ts, following the principle of simple dependency injection.
• Files should be named in dash-case.
• Avoid using classes in the codebase; opt for simple functions instead.
• All committed code must be properly linted using npm run lint:fix and type-checked with npm run type:check.
• Minimize shared logic between services as much as possible.
• Controllers within a router component should ideally call only one service layer, with exceptions for services like audit-log that require access to request object data.