Remember Envoy from earlier in this chapter? It's a very useful tool for efficient application development. Instead of embedding infrastructure services such as logging, monitoring, or networking into your application, you can deploy the Envoy proxy along with your app, just like a sidecar would be deployed next to a motorbike. Together, they can do much more than the app without the sidekick (another name for this pattern).
Using a sidecar can speed up development, as many of the functionality it brings would need to be developed independently by each of your microservices. Because it's separate from your application, a sidecar can be developed using any programming language you find best for the job. The sidecar, along with all the functionality it provides, can be maintained by an independent team of developers and updated independently from your main service.
Because sidecars reside right next to the app they enhance, they can use local means of...
