What are some alternatives?
When comparing Apiary and Gravitee.io, you can also consider the following products
Postman Collections - Biggest library of ready-made API collections for Postman
Apigee - Intelligent and complete API platform
Tyk - Tyk is an open-source API gateway and API management platform.
Amazon API Gateway - Create, publish, maintain, monitor, and secure APIs at any scale
Django REST framework - Django REST framework is a toolkit for building web APIs.
WSO2 API Manager - WSO2 API Manager is a 100% open source enterprise-class solution that supports API publishing, lifecycle management, application development, access control, rate limiting and analytics in one cleanly integrated system.