Overview
Building an API platform means your API is the product—external developers integrate it into their applications. This requires not just backend skills but a developer experience mindset. Your customers are developers who will judge every design decision.
Companies like Stripe, Twilio, and Plaid have set the standard for API excellence. Their APIs are intuitive, well-documented, and reliable—because they treat API design as product design. Poor API design creates support burden and churn.
For hiring, look for backend engineers who understand API design deeply and care about developer experience. Documentation skills matter as much as coding skills. The best API engineers think like their users.
Why API Platform Hiring is Different
When your API is the product, developer experience becomes your competitive advantage. Stripe didn't win just on features—they won on API design that developers love.
Real-World Examples
Stripe is the gold standard for API design. Their API is so well-designed that developers often cite it as the best they've used. This didn't happen by accident—Stripe invested heavily in API UX.
Twilio built a communications empire on APIs that "just work." Their documentation and quick-start guides set industry standards.
Plaid made banking APIs accessible. Their success came from turning complex integrations into simple API calls.
Team Composition for API Platforms
Core Team (3-6 engineers)
| Role | Focus | When to Hire |
|---|---|---|
| Backend Engineer (API) | Core API development | Foundation—hire first |
| Technical Writer | Documentation | Early—docs are product |
| SDK Developer | Client libraries | Once API stabilizes |
| DevRel Engineer | Developer support, samples | At scale |
Hiring Progression
Stage 1: Foundation (2-3 engineers)
- Core API design and implementation
- Basic documentation
- Initial reference implementations
Stage 2: Polish (4-6 engineers)
- Comprehensive documentation
- SDKs for major languages
- Developer portal
Stage 3: Scale (6+ engineers)
- API versioning and migration
- Developer relations
- Advanced tooling
Skills That Matter for API Platforms
Essential Skills
API Design:
- REST/GraphQL principles and trade-offs
- Consistent naming and structure
- Error handling philosophy
- Versioning strategies
Developer Experience Thinking:
- Empathy for API consumers
- Understanding of integration pain points
- Focus on time-to-first-successful-call
- Documentation as first-class concern
Backend Engineering:
- Scalable service architecture
- Authentication and authorization
- Rate limiting and quotas
- Monitoring and observability
Interview Questions
"Walk me through designing an API for [use case]."
Good answers include:
- Starts with user needs, not implementation
- Considers naming carefully
- Thinks about error cases
- Mentions documentation approach
"A developer complains your API is hard to use. How do you investigate?"
Good answers include:
- Seeks specific feedback
- Reviews documentation
- Considers common use cases
- Values developer input
"How do you handle breaking API changes?"
Good answers include:
- Versioning strategy
- Migration paths
- Communication timeline
- Backward compatibility thinking
Common API Platform Hiring Mistakes
Mistake 1: Hiring Backend Engineers Without DX Focus
Why it's wrong: Great backend engineers can build functional APIs that are painful to use. API platform success requires DX thinking.
Better approach: Evaluate API design thinking specifically. Ask candidates to critique existing APIs.
Mistake 2: Underinvesting in Documentation
Why it's wrong: Poor documentation means support burden and churn. Docs are product for API platforms.
Better approach: Value documentation skills when hiring. Consider dedicated technical writers early.
Mistake 3: Ignoring Consistency
Why it's wrong: Inconsistent APIs are confusing. If some endpoints use camelCase and others use snake_case, developers notice.
Better approach: Establish API style guides early. Hire for attention to detail.
API Platform Team Structure
Core Roles
API Engineers:
Build the API endpoints themselves. Strong backend skills with DX focus. Usually 2-4 engineers depending on API complexity.
Technical Writers:
Create and maintain documentation. For API platforms, documentation is product. Consider hiring technical writers earlier than you think.
SDK Developers:
Build client libraries for major languages. Usually comes after API stabilizes. May be the same engineers building the API.
DevRel/Developer Advocates:
Support external developers, create tutorials, gather feedback. Important at scale; less critical early.
Team Size by Stage
| Stage | Team Size | Focus |
|---|---|---|
| Early (MVP) | 2-3 | Core API, basic docs |
| Growth | 4-6 | Full docs, initial SDKs |
| Scale | 6-10+ | Multiple SDKs, DevRel, support |
Start lean—API platforms don't need large teams initially.
API Design Excellence
What Sets Great APIs Apart
The best APIs share common characteristics that developers love:
Consistency:
- Predictable naming conventions across all endpoints
- Consistent error response formats
- Uniform authentication patterns
- Standard pagination and filtering
Discoverability:
- Intuitive resource naming
- Logical URL structure
- Comprehensive documentation
- Interactive API explorers
Error Handling:
- Clear, actionable error messages
- Appropriate HTTP status codes
- Error codes for programmatic handling
- Suggestions for resolution
Building Developer Trust
API platforms live or die by developer trust:
Reliability:
- High uptime and availability
- Consistent response times
- Graceful degradation under load
- Clear status communication
Stability:
- Thoughtful versioning strategy
- Long deprecation timelines
- Migration guides for breaking changes
- Backward compatibility when possible
Support:
- Responsive developer support
- Active community forums
- Regular communication about changes
- Listening to developer feedback
Evaluating API Platform Engineers
Technical Assessment
API Design Exercise:
Give candidates a scenario and ask them to design an API:
- Do they start with user needs?
- Is the naming intuitive and consistent?
- How do they handle edge cases?
- What's their approach to versioning?
Code Review:
Show them an existing API and ask for feedback:
- Can they identify design issues?
- Do they consider developer experience?
- How do they prioritize improvements?
Documentation Skills
For API platforms, documentation is product:
- Ask for writing samples
- Evaluate clarity and completeness
- Assess ability to explain complex concepts
- Check for empathy with API consumers
Developer Experience Mindset
The best API engineers think like their users:
- They've integrated APIs themselves
- They understand developer frustrations
- They prioritize time-to-first-successful-call
- They value simplicity over cleverness