In a static world, you put the IP of your database in a config file and you're done. In a modern world, your database is three replicas with rotating IPs, your services come and go with autoscaling, and pod IPs change every deploy. Something has to bridge 'I want to talk to the user-service' and 'send to 10.0.4.27:8080.' That something is service discovery.
Engineering Craft
TypeScript, CI/CD, databases, observability -- the skills that make code production-ready.