Can Zuul Edge Server be used without Eureka / Ribbon

Yes, Of course you can. Actually, by default, if you use @EnableZuulProxy with the Spring Boot Actuator, you enable two additional endpoints:

• Routes
• Filters

application.yaml

zuul:
  routes:
    users:
      path: /myusers/**
      url: https://example.com/users_service

These simple url-routes do not get executed as a HystrixCommand, nor do they load-balance multiple URLs with Ribbon.

Yo can get more information from here.

A sample usage can be like this:

shared.microservice.customer.service1.url=zttp://127.0.0.1:8080/shared/microservice/customer/

shared.microservice.customer.service2.url=zttp://127.0.0.1:8181/shared/microservice/customer/

ribbon.eureka.enabled = false

zuul.routes.customer-micro-service.path: /shared/microservice/customer/**

zuul.routes.customer-micro-service.serviceId: customers
customers.ribbon.listOfServers = 

zttp://ip:port1/shared/microservice/customer/,zttp://ip2:port2/shared/microservice/customer/

Yes, it is totally possible.You have to use @EnableZuulProxy on your config class and config it something like this :

zuul:
  routes:
    yourService:
      path: /yourService/**
      serviceId: yourService

ribbon:
  eureka:
    enabled: false

yourService:
  ribbon:
    listOfServers: localhost:8080