Test First

accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/test-first.png
name: Test First
description: A software development approach where tests are written before the implementation code, ensuring code quality
  and driving design decisions through test requirements. Test-first development is the foundational principle behind test-driven
  development (TDD) and behavior-driven development (BDD), where the specification of expected behavior is captured in executable
  tests before any production code is written.
url: https://en.wikipedia.org/wiki/Test-driven_development
tags:
- Behavior-Driven Development
- Best Practices
- Methodology
- Software Design
- Software Development
- Testing
created: '2025'
modified: '2026-05-03'
apis:
- name: Cucumber API
  description: REST API and tooling for Cucumber BDD framework supporting test-first development with Gherkin feature files,
    scenario definitions, and step implementations.
  humanURL: https://cucumber.io
  baseURL: https://cucumber.io
  tags:
  - Behavior-Driven Development
  - Gherkin
  - Test Automation
  - Testing
  properties:
  - type: Documentation
    url: https://cucumber.io/docs/cucumber/
  - type: GitHubRepository
    url: https://github.com/cucumber/cucumber-js
- name: Pact Broker API
  description: REST API for Pact Broker contract testing service, enabling consumer-driven contract testing where consumer
    tests define the API contract before providers implement it.
  humanURL: https://docs.pact.io
  baseURL: https://your-pact-broker.example.com
  tags:
  - Consumer-Driven Contracts
  - Contract Testing
  - Microservices
  - Test-First
  properties:
  - type: Documentation
    url: https://docs.pact.io
  - type: GitHubRepository
    url: https://github.com/pact-foundation/pact_broker
  - type: OpenAPI
    url: https://raw.githubusercontent.com/pact-foundation/pact_broker/master/lib/pact_broker/api/pact_broker.json
- name: Stoplight API
  description: API design-first platform enabling teams to write API specifications before implementation, supporting test-first
    development with mock servers, contract testing, and API style guides.
  humanURL: https://stoplight.io
  baseURL: https://api.stoplight.io
  tags:
  - API Design
  - Contract Testing
  - Mock Servers
  - Test-First
  properties:
  - type: Documentation
    url: https://meta.stoplight.io/docs/platform
  - type: APIReference
    url: https://meta.stoplight.io/docs/stoplight-api
- name: Microcks API
  description: Open-source cloud-native tool for API mocking and contract testing, supporting test-first development by generating
    mocks from OpenAPI, Postman, and gRPC specifications.
  humanURL: https://microcks.io
  baseURL: https://your-microcks.example.com/api
  tags:
  - API Mocking
  - Contract Testing
  - Open Source
  - Test-First
  properties:
  - type: Documentation
    url: https://microcks.io/documentation/
  - type: GitHubRepository
    url: https://github.com/microcks/microcks
- name: Dredd API
  description: Command-line HTTP API testing framework that validates API implementations against API Blueprint or OpenAPI
    descriptions, enabling test-first API development.
  humanURL: https://dredd.org
  baseURL: https://dredd.org
  tags:
  - API Testing
  - Contract Testing
  - OpenAPI
  - Test-First
  properties:
  - type: Documentation
    url: https://dredd.readthedocs.io
  - type: GitHubRepository
    url: https://github.com/apiaryio/dredd
common:
- type: DomainSecurity
  url: security/test-first-domain-security.yml
- type: Documentation
  url: https://en.wikipedia.org/wiki/Test-driven_development
- type: Documentation
  url: https://www.agilealliance.org/glossary/tdd/
- type: Features
  data:
  - name: Specification Before Implementation
    description: Write executable test specifications that define expected behavior before writing any production code.
  - name: API Contract Definition
    description: Define the API contract through tests before the implementation exists, ensuring design clarity.
  - name: Mock-First Development
    description: Use mock servers generated from specifications to enable parallel frontend and backend development.
  - name: Living Documentation
    description: Tests serve as up-to-date documentation of how the system is expected to behave.
  - name: Fail Fast Feedback
    description: Discover design issues early by specifying tests before implementation reveals constraints.
  - name: Consumer-Driven Contracts
    description: Let API consumers define their expectations as tests that the API provider must satisfy.
- type: UseCases
  data:
  - name: API-First Design
    description: Write OpenAPI specifications and generate tests from them before building the implementation.
  - name: Consumer-Driven Contract Testing
    description: API consumers publish test expectations that API providers must verify in their CI pipelines.
  - name: Behavior-Driven Development
    description: Use Gherkin feature files to define expected system behavior before writing implementation.
  - name: Parallel Development
    description: Enable frontend and backend teams to develop in parallel using mock servers from specifications.
  - name: Specification Compliance
    description: Validate that API implementations comply with their published specifications using test-first assertions.
- type: Integrations
  data:
  - name: OpenAPI
    description: Generate test-first stubs and mocks directly from OpenAPI specifications.
  - name: Cucumber
    description: Use Gherkin scenarios as the test-first specification for behavior-driven development.
  - name: Pact
    description: Apply consumer-driven contract testing where consumer tests define provider expectations.
  - name: Prism
    description: Use Stoplight Prism to mock APIs from OpenAPI specs enabling test-first development.
- type: JSONSchema
  url: json-schema/test-first-specification-schema.json
- type: JSONSchema
  url: json-schema/test-first-contract-schema.json
- type: JSONSchema
  url: json-schema/test-first-mock-schema.json
- type: JSONLD
  url: json-ld/test-first-context.jsonld
- type: Vocabulary
  url: vocabulary/test-first-vocabulary.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
  url: https://apievangelist.com