API Design Considerations

Designing APIs isn’t just about making data accessible—it’s about ensuring stability, flexibility, and future-proof integrations for your business. Here are the pillars for robust API design in modern SaaS environments.

1. Design for Change: Embrace API Versioning

Change is inevitable. A great API strategy acknowledges that both the data and business requirements will evolve. Versioning is your insurance policy:

• Version every public API (e.g., /v1/orders), even if you only have one client at the start. This future-proofs your integration and makes upgrades predictable.
• With explicit versioning, you can launch new features, fix bugs, or refactor without breaking live applications.
• Multiple versions running in parallel let client teams migrate on their own schedule and safely roll back if issues arise.

tip

Best Practice: Only introduce a new major version for breaking changes. Additive, backward-compatible enhancements can stay in the same version. For more information, see Manage API Versions.

2. Deliver Upgrades Without Disruption

Zero-downtime is the standard for today’s APIs. Achieve this by:

• Publishing new versions without taking old ones offline—run them side by side.
• Rolling out client updates gradually (blue-green, canary, or rolling deployments).
• Always upgrade the server (API) before the client apps.
• Monitoring real usage—only retire old versions once you’re certain all clients have moved.

Why? This approach lets you experiment, validate, and recover quickly—no more coordinated late-night upgrades or risky one-shot deployments.

3. Speak a Common Language: Consistent Naming & Structure

Naming isn’t just cosmetic—it creates consistency across APIs and teams, making it easier to understand, maintain, and scale.

• Use plural nouns for endpoints that return collections (e.g., /v1/customers, /v1/product_metrics)

• Reflect real business entities in endpoint names—avoid technical or implementation-based terms like List, Collection, or Document

  e.g. /v1/customer_list ❌ /v1/customers ✅

• Use consistent naming patterns across all APIs. TapData follows snake_case for both endpoint paths and response fields to align with common data conventions

• Ensure term consistency—if you use customer_id in one API, don’t rename it client_id in another unless they truly represent different things

4. Minimize Surprises: Protect Integrations from Breaking Changes

Don’t break your users’ apps unexpectedly. Guard against disruptions by:

• Never removing or renaming fields, changing their types, or altering default outputs in a live version
• Only add new parameters as optional, with safe defaults, so old clients remain unaffected
• Use explicit filter and fields parameters so consumers control what they get—and aren’t surprised by new fields

If a breaking change is truly required, launch it as a new major version and follow your rollout plan.

5. API Flexibility: Serve Many Use Cases, Without Sprawl

Your data models will support many user journeys. Design your APIs to reflect this:

• Separate detail and list endpoints, with appropriate default fields for each
• Allow field selection, so clients can get only what they need
• Create specialized endpoints for historical records or nested/embedded data if required—but avoid unnecessary duplication

tip

Well-designed APIs let clients flexibly query what they need, but keep a sensible, opinionated default for each use case.

6. Build Resilient APIs: Rate Limiting & Access Control

A good API is not just usable, but also robust:

• Apply rate limits to every endpoint based on business impact, not just raw traffic
• Ensure that resource spikes or abusive clients on one API can’t degrade the experience for everyone else
• Use role-based access and client-level permissions for sensitive or premium data

Design Checklist

Principle	Why It Matters
Explicit versioning	Enables safe, staged upgrades & independent rollbacks
Zero-downtime deployment	Keeps systems online and users happy
Consistent naming/structure	Makes APIs discoverable and reduces onboarding time
Backward compatibility	Prevents outages, protects integrations
Flexibility for use cases	Delivers value to many teams, reduces API sprawl
Rate limiting & security	Keeps the platform stable, safe, and scalable

Bottom line: Great API design is as much about the developer and business experience as it is about the code. Prioritize clarity, stability, and evolvability. When in doubt—design for the next team (or your future self) who will need to use and extend your APIs.