ContractFirstE
ContractFirstE is a software development approach that treats contract definitions as the primary source of truth for building distributed systems. In a ContractFirstE workflow, teams specify the interface, data models, and behavioral expectations before writing service logic, ensuring that both producers and consumers agree on the contract from the outset.
Contracts are expressed in formal specifications such as OpenAPI, AsyncAPI, Protocol Buffers, or similar interface definition
Typical workflow involves defining the contract, automatically generating server skeletons and client bindings, implementing service logic
Advantages include early error detection, clearer interface boundaries, improved onboarding, and better API governance in large
In practice, ContractFirstE is used in API-first programs, microservices architectures, and messaging systems. It aligns with
See also: API-first design, contract testing, OpenAPI, AsyncAPI, consumer-driven contracts.