Nobody talks about this part. When everything lived in one repo, we'd merge to main and deploy. Twenty minutes, done. After splitting into services, a feature touching three services meant coordinating three deployments, three releases, three sets of database migrations.
The breaking point came during our Black Friday prep. We needed to update the checkout flow, which touched the cart service, inventory service, and payment service. The changes were dependent—you couldn't deploy one without the others or the app would break.
We learned the hard way that backward compatibility isn't optional in microservices. That November sprint, we rewrote the feature to work in stages. First deployment: the services could handle both old and new message formats. Second deployment: start sending new formats. Third deployment: remove old format support. What used to be one deploy became three, spaced over two weeks.
The team nearly revolted. "We should've stayed with the monolith" became our standup joke.
Then something shifted around month seven. We'd learned to design for independent deployment. New features got built with versioned APIs from day one. We started using feature flags to decouple deployment from release. Last month, we deployed 47 times across all services. Zero coordination needed.
The first six months almost killed the project. But we're shipping faster now than we ever did with the monolith.