In the previous chapters, you learned how to build a micro-frontends-style site using client-side integration techniques like links, iframes, and Ajax. You’ve also learned how to run a shared web server that routes incoming requests to the responsible team for a specific part of the application. In this chapter, we will build upon these and look at server-side integrations. Assembling the markup of different fragments on the server is a widespread and popular solution. Many e-commerce companies like Amazon, IKEA, and Zalando have chosen this way.
Server-side composition is typically performed by a service that sits between the browser and the actual application servers, as illustrated in figure 4.1. The most significant benefit of server-side integration is that the page is already fully assembled when it reaches the customer’s browser. You can achieve incredibly good first-page load speeds that are hard to match using pure client-side integration techniques.