Organizing Your Backend: Services or Helpers?
The difference between services and helpers, and how to organize them in your backend folder structure.
When developing a robust backend, code organization is crucial to maintainability and scalability. In this article we'll look at the difference between two key components — services and helpers — and how to organize them in the folder structure.
Service: the backbone of business logic
Services are the heart of your backend. They encapsulate application-specific business logic, handle complex operations, interact with the database, and enforce domain rules.
- Business logic abstraction: services abstract complex operations, providing a clean interface for the rest of the app. This increases cohesion and makes the code easier to reason about.
- Database interaction: services are usually tied to persistence — managing queries, updates, and ensuring data integrity.
- Reusability and scalability: encapsulating business logic in services produces reusable building blocks that scale with the project.
Helper: versatile utilities for generic functionality
Where services are application-specific, helpers are Swiss army knives offering generic utility functions.
- Generic functionality: helpers hold functions that aren't tied to business logic but are essential for common tasks — string manipulation, date formatting, generic validations.
- Reuse across contexts: because they're decoupled from domain rules, helpers can be used anywhere — promoting consistency and reducing duplication.
- Simpler maintenance: isolating utilities in helpers means a single place to update a generic function.
Structuring your folders
/src/services -> userService.ts, orderService.ts, paymentService.ts
/src/helpers -> stringHelper.ts, dateHelper.ts, validationHelper.ts
When to use each
The rule of thumb:
- Services for application-specific business logic.
- Helpers for generic, utility functionality.
This separation keeps the code organized, eases maintenance, and supports sustainable growth.
PS. While the service/helper distinction shows up most in the MVC pattern, I prefer folder-by-feature over folder-by-type — though many legacy systems still use the latter. That's a topic for another post.
January 15, 2024 · Brazil