What does HackerNews think of microservices-demo?

> It is extremely difficult to change a monolith’s technology or language or framework because all components are tightly coupled and dependent on each other. As a result, even relatively small changes can require lengthy development and deployment times.

I disagree with this so much. I have personally worked with Rails application monoliths and Node.js microservices and I can tell you that making changes on the monolith is muliple times easier mostly depending on the code structure. I would take a properly structured monolith any day. This not only includes code/features but also deployments. Adding more services introduces more complexity in the deployment architecture as well.

A good example of this is just by looking at the GitLab codebase https://gitlab.com/gitlab-org/gitlab, it's a monolith but has good abstractions/structure vs say the Google Microservices Demo app https://github.com/GoogleCloudPlatform/microservices-demo which is not tightly coupled but introduces more complexity from implementation to deployment.

This is not a book but a well-maintained and documented open source sample by the Google Cloud Team of a cloud-native application with "10 microservices showcasing Kubernetes, Istio, gRPC and OpenCensus"

https://github.com/GoogleCloudPlatform/microservices-demo

Give https://github.com/GoogleCloudPlatform/microservices-demo a try, it inspired this project you linked to.