How did the world reach microservices?

Introduction

Imagine a small team in a cramped office, working on a single piece of software. Everything lived in one big package the code, the build scripts, the tests were all tied together in a neat bundle. Deployments were simple: one pipeline, one click, and voilà, the product was live. Back then, it was efficient, even comforting.

But the company grew. The team doubled, then tripled. Suddenly, that “neat bundle” became a battlefield. Developers stepped on each other’s toes, merge conflicts piled up, and one person’s tiny change could bring the whole system crashing down. Releases turned into high-stakes events. “Did we break anything this time?” became the office’s unofficial catchphrase.

So, we tried a fix. We broke the giant package into smaller ones, giving each team their own corner to work in. It helped… for a while. But we were still tied together at the hip during deployments. The real breakthrough came when we started splitting not just code, but responsibility — separate builds, separate deployments, even separate infrastructure. And just like that, the path to microservices had begun.

The Monolith Days

In Monolith architecture all developers contribute to a single, unified code package. Developer1, Developer2, and Developer3 each make their commits directly into the same shared codebase. Once all changes are merged, the entire application is built and deployed as a single unit — first to a beta environment, and then to production. This approach means that any change, no matter how small, requires rebuilding and redeploying the whole system. While simple in setup, it creates a high risk of conflicts, slows down release cycles, and increases the blast radius of failures since every update affects the entire application.

Now imagine, the team grows to 150 developers. All the developers are now committing to the same package, some of them to the same files. After a point it becomes extremely difficult for the developers to keep pulling each other's changes and resolving conflicts.

Modularization

One easy solution to the problem is to divide the code base into multiple packages and give ownership of each package to individual teams. For eg: For an ecommerce platform code for Orders, Inventory, Returns etc. can be split into different packages. All the packages are the built together in the end to be deployed to beta and prod environments.

Now imagine the team grows to a 1000 people. It might happen that there is a certain feature in the returns package that needs to be deployed whereas the orders team is not ready to deploy changes to prod. In this case, returns team needs to wait for orders team to be ready for prod deployment or the orders team will need to revert their changes.

Also, you would need a separate team just to maintain the deployment pipeline and for building consensus between multiple teams.

Microservices

This is where Microservices comes into picture. Along with separate packages, what if we split the deployment pipelines and infrastructure between multiple teams? The combination of a separate package + pipeline + infrastructure is called as a microservice.

Each microservice then interacts with other microservices through APIs.

This gives a team freedom to deploy their own changes whenever they want, without any conflicts. Individual teams manage their own infra and pipelines. Any blockers or failures don't block other teams. The huge code package and build created in Monolith also becomes smaller leading to easier code maintenance, faster builds and deployment times.

The downside of this approach is that there is higher latency between service interactions when compared to a monolith as the infrastructure is separate and services interact via API calls which are network calls.

Conclusion

Microservices aren’t the inevitable destiny of every software project but they’re the result of scaling pains that monoliths and modularization can no longer solve. As teams grow and products become more complex, the need for independent ownership, faster releases, and reduced blast radius pushes organizations toward breaking systems into smaller, autonomous parts.

But with that freedom comes new responsibilities: managing more infrastructure, handling inter-service communication, and keeping an eye on performance overhead. The real lesson? Architecture is a journey. Start simple, evolve as you grow, and choose the approach that best matches your team’s size, culture, and goals not just what’s trending in the industry.