What's up, everyone! Roberto Hernando here. Today I've got a confession, one of those that makes you sweat bullets and reminds you that no matter how experienced you feel, there's always a little pebble in your shoe waiting to trip you up. And this time, that pebble was called "microservices".
We all talk about them, right? That they're the be-all and end-all, that they scale better, that they enable more agile teams... and yeah, in theory, all of that is true. The problem is, there's an abyss between theory and practice. And I, naive as I was, dove headfirst into crossing it without the right life jacket.
The Temptation of Dismantling the Monolith
It all started with a project that had years of development behind it. A good old monolith, the kind where you know every nook, every shortcut, every inherited bug. It was stable, it worked, but it was growing so much that it was starting to drown in its own weight. Deployments became slow, new features took ages to release, and if one team touched something, we prayed it wouldn't break the rest.
The decision seemed obvious: microservices. It was time to modernize, to give the application and ourselves a breather. The vision was clear: break that giant down into small, independent units, each with its own database, deploying separately. Sounds great, huh! The problem is I focused too much on the "what" and not enough on the "how" and, especially, on the "why for each fragment".
My First Big Screw-Up: The Wrong Granularity
Here's the crux of the matter. My first colossal mistake was how I decided to fragment the monolith. In my eagerness to have "micro" services, I went to the extreme. I thought: "If it does one thing, it's a service." So I started creating services for things that, in retrospect, were too small and intimately linked. For example, a service for authentication, another for authorization, one for user management, another for user profiles, another for user addresses... and so on!
The idea was good in theory: each service super specialized. The problem was, in the end, I had a bunch of services constantly depending on each other. To perform a simple "view authenticated user profile" operation, I needed to call the authentication service, then the authorization service, then the user service to get basic info, and then the profile service to get the profile details. Imagine the latency and complexity!
The code started to become a puzzle of network calls. Every frontend request could trigger a cascade of inter-service requests. And not only that, deployment became a nightmare. If you changed something in the "user addresses" service, you had to make sure the services depending on it didn't break. The agility we were looking for vanished, replaced by a constant headache and a ton of potential failure points.
I remember sleepless nights trying to debug a transaction that failed because a specific service was down, or because an incompatible version of another service had been deployed. Coordination between teams became a minefield. It felt like we had gone from one big problem to many small, interconnected problems, and that, my friends, is much worse.
Why Do I Think This Is Important to Share?
Because I believe there's a lot of hype around microservices. They're sold as the magic solution for all the ills of monolithic applications, but the pitfalls aren't talked about enough. Migrating to microservices isn't just a technical change; it's a cultural and organizational shift. And if you don't approach it with the right mindset, you can end up in a much more complicated situation than you were before.
This mistake taught me that not all monoliths need to be dismantled into microservices. Sometimes, a "macroservice" or even a well-structured monolith is still the best option. The key isn't the number of services, but their real independence and the cohesion within each one. Fragmentation should respond to clear business boundaries, not an obsession with meaningless "micro-specialization".
What I Learned (and Don't Want You to Repeat)
After that experience, my approach changed radically. Here are some lessons I treasure:
1. Granularity is CRUCIAL: Don't divide by technology or minor functionality. Divide by business domains. Think about which part of your application represents an autonomous business unit. If a part can live and evolve independently of others, then it might be a good candidate for a service.
2. Synchronous vs. Asynchronous Communication: In my first attempt, I abused synchronous communication (direct calls from one service to another). This creates coupling and fragility. Whenever possible, I prefer asynchronous communication, using message queues or events. This decouples services and makes them more resilient.
3. The Cost of Distributed Complexity: Every service adds complexity: deployment, monitoring, orchestration, distributed data management, eventual consistency... If your team isn't ready to handle this complexity, it's better to be cautious. Sometimes, simplifying the monolith is more efficient than distributing the problem.
4. Don't Reinvent the Wheel (Too Much): In the beginning, each service had its own logging system, monitoring, etc. This is unsustainable. It's vital to have a unified strategy for these things, even in a microservices environment.
5. The "Distributed Monolith" Anti-Pattern: This is what I had unintentionally created. Small, coupled services that, together, behaved like a monolith but with all the problems of distribution. Avoid this at all costs!
Final Thoughts
Microservices have their place, and they can be a fantastic architecture for certain applications and organizations. But they are not a silver bullet. They require careful planning, a deep understanding of your business domain, and the organizational maturity to manage them. My first attempt was a reality check, a lesson in humility that made me appreciate the beauty and complexity of good architectural design.
If you're thinking about migrating, do it wisely. Research, learn from others' mistakes (and your own, if you dare), and above all, don't be afraid to take a step back if you see the path getting unnecessarily complicated. Sometimes, the most elegant solution is the one that avoids over-engineering.
I hope this confession is helpful to you! Until next time.