API-First and Platform Thinking

API-First and Platform Thinking represent an architectural and product mindset where internal and external consumers interact with systems via stable, self-service, and discoverable APIs or platforms.
These approaches support modularity, reuse, autonomy, and scalable collaboration — enabling teams to build on each other’s work rather than reinventing it.

Level 1 – Initial (Ad Hoc)

APIs and services are developed reactively and inconsistently.
Internal consumers must rely on direct database access, tribal knowledge, or custom integration to consume functionality.

  • APIs are undocumented or built as afterthoughts
  • There is no standard or consistent API design approach
  • Teams duplicate logic or bypass layers due to poor reuse
  • Inter-team collaboration requires deep coordination
  • No concept of platform or internal productisation

Level 2 – Managed (Emerging Practice)

Teams begin exposing functionality through APIs, but approaches vary and reuse is limited.

  • Some APIs are documented and reused internally
  • REST or GraphQL patterns may be emerging but not standardised
  • Teams provide ad hoc support for consumers rather than self-service
  • There is increasing awareness of the need for service abstraction
  • Platform capabilities may exist but are immature and team-specific

Level 3 – Defined (Standardised)

API-first design and platform thinking are established practices.
Teams expose services with consistent standards and treat internal capabilities as products.

  • APIs are designed before implementation and aligned with consumer needs
  • Documentation, versioning, and testing are standardised
  • Platforms (e.g. developer portals, reusable CI/CD, observability) enable reuse and self-service
  • APIs are discoverable and usable without deep coordination
  • Teams are incentivised to produce reusable, composable services

Level 4 – Quantitatively Managed (Measured & Controlled)

APIs and platforms are managed with service-level metrics and consumer feedback.
Platform usage and service experience are continuously improved.

  • Metrics include API usage, latency, error rates, time-to-first-use, and consumer satisfaction
  • Versioning, deprecation, and dependency policies are enforced
  • Consumer teams are treated as users with defined expectations
  • Teams track internal adoption and value from shared services
  • Governance balances autonomy with alignment (e.g. golden paths, standards)

Level 5 – Optimising (Continuous Improvement)

API-first and platform thinking drive scale, innovation, and speed across the organisation.
Platforms are treated as products and evolve continuously based on feedback and system needs.

  • Platforms support rapid onboarding, experimentation, and delivery
  • Platform teams operate like product teams with roadmaps, SLAs, and customer focus
  • APIs evolve based on real-time analytics and consumer feedback
  • Internal developer experience is a strategic priority
  • Platform thinking enables organisational modularity and ecosystem-scale delivery