API Documentation & Developer Portal (OpenAPI 3.0)

Employer
Digital
Project parameters
Type of cooperationOne-time project
SectionTexts and translation
Prepaymentwithout prepayment
Payment methodsCash, Bank transfer
Acceptance of requestsfrom today, 06:57 until Sep 2, 2026
Project description
Our REST API has grown to more than forty endpoints and, at this point, not one of them is documented. Developers integrating with us are effectively reverse-engineering the API from example requests, which slows everyone down and generates a steady stream of avoidable support questions. We want to fix that properly by commissioning a complete OpenAPI 3.0 specification together with a polished developer portal that people can actually read and try things in.
We are looking for someone who combines strong technical writing with real hands-on API experience, because this job is as much about clear explanation as it is about accurate schemas. You will produce a full OpenAPI 3.0 YAML spec covering every endpoint, its request and response schemas and its error codes, then turn that into interactive docs hosted with Swagger UI or Redoc. On top of the reference we need a Getting Started guide walking through authentication, rate limits, pagination and error handling, plus copy-paste code examples in cURL, PHP and JavaScript for each major endpoint. Round it out with a Postman collection and a changelog template for version history.
We will provide API access, our existing internal code docs and the full endpoint list; we are expecting the finished documentation within twenty-one days.
Deliverables:
— 1. OpenAPI 3.0 YAML spec — all endpoints, request/response schemas, error codes
— 2. Interactive API docs — Swagger UI or Redoc hosted page
— 3. Getting Started guide — authentication, rate limits, pagination, errors
— 4. Code examples — cURL, PHP, JavaScript for each major endpoint
— 5. Changelog — version history template
— 6. Postman collection export
Process:
— We provide: API access, existing codebase docs, endpoint list
— You deliver: complete docs in 21 days
— Strong technical writing plus API experience required
We are looking for someone who combines strong technical writing with real hands-on API experience, because this job is as much about clear explanation as it is about accurate schemas. You will produce a full OpenAPI 3.0 YAML spec covering every endpoint, its request and response schemas and its error codes, then turn that into interactive docs hosted with Swagger UI or Redoc. On top of the reference we need a Getting Started guide walking through authentication, rate limits, pagination and error handling, plus copy-paste code examples in cURL, PHP and JavaScript for each major endpoint. Round it out with a Postman collection and a changelog template for version history.
We will provide API access, our existing internal code docs and the full endpoint list; we are expecting the finished documentation within twenty-one days.
Deliverables:
— 1. OpenAPI 3.0 YAML spec — all endpoints, request/response schemas, error codes
— 2. Interactive API docs — Swagger UI or Redoc hosted page
— 3. Getting Started guide — authentication, rate limits, pagination, errors
— 4. Code examples — cURL, PHP, JavaScript for each major endpoint
— 5. Changelog — version history template
— 6. Postman collection export
Process:
— We provide: API access, existing codebase docs, endpoint list
— You deliver: complete docs in 21 days
— Strong technical writing plus API experience required