Kong

Kong is an API gateway that sits in front of your services to handle authentication, traffic control, logging, and request transformation. It runs on OpenResty, which is Nginx plus Lua, making it fast and event-driven. You can route requests to multiple upstream services, apply plugins per route or globally, and monitor everything through a RESTful admin API.

Kong supports plugins for OAuth2, JWT, ACLs, rate limiting, and request/response transformations. It integrates with service meshes like Kuma, and works on Kubernetes via Kong Ingress Controller. The database can be PostgreSQL, Cassandra, or DB-less mode. Lua plugins can be written inline or installed from the plugin hub. The community edition includes all core features with no limit on the number of services or plugins.

It is best suited for DevOps teams and platform engineers building internal developer platforms or managing microservices in production. The open source version is Apache 2.0 licensed. Kong Inc. also offers enterprise versions with additional security features and dedicated support. Notable adopters include Samsung, Honeywell, and Yahoo Japan.