What are some alternatives?
When comparing Amazon API Gateway and Apigee, you can also consider the following products
Postman Collections - Biggest library of ready-made API collections for Postman
Paw.cloud - Paw is a REST client for Mac.
Gravitee.io - Gravitee.io is a flexible, lightweight and an open source API management solution.
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.
Django REST framework - Django REST framework is a toolkit for building web APIs.
Tyk - Tyk is an open-source API gateway and API management platform.