How do I simplify my backend APIs?

To simplify backend APIs, aim to reduce surface area, inconsistency, and special cases. A good API is easy to use correctly and hard to use incorrectly.

1) Start with the core use cases

Don’t model every internal detail. Define:

• What are the top 5–10 client actions?
• What data do clients actually need?
• What workflows should be one call vs. many?

If an endpoint exists only because of internal structure, consider removing it or merging it into a more useful operation.

2) Use consistent resource design

Prefer predictable patterns:

• GET /users/{id}
• POST /users
• PATCH /users/{id}
• DELETE /users/{id}

Keep naming consistent:

• Use nouns for resources, not verbs
• Use the same term everywhere for the same concept
• Avoid multiple endpoints that do nearly the same thing

3) Reduce endpoint count

Common simplifications:

• Merge overlapping endpoints
• Replace many tiny endpoints with fewer, more flexible ones
• Use query parameters for filtering/sorting/pagination
• Use a single update endpoint instead of separate “change name”, “change email”, etc., unless there’s a strong reason

4) Standardize request and response shapes

Make responses predictable:

• Same envelope format for all endpoints, if used
• Same error structure everywhere
• Same pagination format everywhere
• Same field naming convention everywhere

Example consistent error shape:

{
  "error": {
    "code": "INVALID_INPUT",
    "message": "email is required",
    "details": [{"field": "email", "issue": "missing"}]
  }
}

5) Keep payloads minimal and purposeful

Only return what clients need:

• Avoid deeply nested responses unless necessary
• Avoid giant “everything” objects
• Support field selection if clients need partial data
• Use pagination for list endpoints

6) Make operations idempotent when possible

This reduces client complexity:

• PUT/PATCH for updates
• Idempotency keys for create/payment-like actions
• Avoid endpoints that behave differently based on hidden state

7) Hide internal complexity behind service boundaries

If your backend has many internal steps, combine them behind one API:

• Orchestration in the backend, simplicity in the API
• Don’t expose internal tables, microservices, or workflow steps directly

8) Version carefully

Versioning can help avoid API sprawl:

• Prefer backward-compatible changes
• Deprecate old endpoints instead of creating near-duplicates
• Use a clear policy for removal

9) Document only the important behavior

A simple API still needs clear docs:

• What the endpoint does
• Required/optional fields
• Example request/response
• Error cases
• Rate limits / auth requirements

If docs are long, the API may be too complex.

10) Watch for “too many options”

Complexity often comes from optional parameters, flags, and modes:

• Too many boolean flags
• Multiple ways to do the same thing
• Hidden behavior based on parameter combinations

Prefer:

• Sensible defaults
• Fewer parameters
• Separate endpoints only when semantics truly differ

11) Design from client experience backward

Ask:

• Can a new developer understand this in 5 minutes?
• Can they guess the endpoint names?
• Can they use the API without reading everything?
• Are error states obvious?

If not, simplify.

A practical simplification process

1. List all endpoints
2. Group by business capability
3. Find duplicates and overlaps
4. Identify the top client workflows
5. Merge or remove rarely used endpoints
6. Standardize naming, errors, pagination, auth
7. Deprecate old APIs gradually

A simple rule of thumb

If an endpoint:

• is hard to explain,
• is rarely used,
• duplicates another endpoint,
• or exposes internal implementation,

it probably should be simplified or removed.

If you want, I can also help you:

• review your current API design,
• propose a simpler REST structure,
• or suggest a “before/after” refactor for a specific set of endpoints.