Microservices vs. Monoliths: Lessons Learned & How to Choose
Whether you're building your first MVP, scaling a growing product, or rethinking legacy systems, architectural choices matter.
It's not about picking sides or favorites… What works for some teams might not work for others, and ultimately, the right choice is the one that aligns best with your organization’s context and needs.
To make those decisions easier, this blog breaks down the two approaches —monolithic vs. microservices architecture— and their core differences.
Let’s start by revisiting the fundamentals.
Understanding monolithic architecture
Picture a monolith for what it is—one solid, unified structure. In software, “monolithic” architecture takes the same idea: all parts of an application are built and deployed together as a single, inseparable unit.
A classic way to picture this model is as a big box, with everything from the user interface to the database logic packed tightly into one place.
Monolithic architecture typically involves:
- A single codebase: All functionality lives in one unified project or repository.
- Tightly coupled components: Changes in one part of the system often affect others.
- Unified deployment: The entire application is compiled, built, and deployed as a whole—even for minor updates.
- Shared resources: Components commonly share memory, data models, and infrastructure.
Despite the recent hype around microservices, monolithic architecture has been around for a long time, and it’s still getting the job done for plenty of teams. As IBM experts point out, the fact that monoliths are still in use after decades says a lot in an industry defined by constant change.
Let’s now explore some of the benefits it offers.
Advantages of monolithic architecture
What makes monolithic architecture stand the test of time is its simplicity and ease of development, especially for small and medium applications.
Development stays simple
Monoliths keep things straightforward. With a single codebase, teams can build faster, stay organized, and avoid the overhead that comes with splitting everything into services. It’s often just the right fit for small or mid-sized projects.
Simplified deployment
When the whole app ships as one package, deployment gets easier to manage. Primarily early on, this can save time and reduce friction.
Debugging tends to be easier
Since everything runs in one place, logs, stack traces, and application state are centralized. This makes it easier to spot and fix issues without having to track them across multiple services.
Disadvantages of monoliths
Yet, this architecture comes with its limitations, particularly as applications grow over time.
Locked into early decisions
Monoliths usually stick to a single tech stack. The framework, language, and architecture choices made early on are hard to change later — and switching can be costly and complex.
High coupling between features
In a monolithic setup, features and components are closely connected. That means a small change in one part of the system might have unexpected effects elsewhere. It also slows teams down, since updates often require coordinating across the whole codebase.
Maintenance becomes harder over time
At the start, it’s all clean and manageable. But as features pile on, the codebase can become harder to navigate. Onboarding new developers takes longer, refactoring feels risky, and even small fixes can mean rebuilding and redeploying the entire app.
Scaling limitations
Monolithic apps can be scaled, but not always efficiently. Since all components are deployed together, the whole system often needs to be scaled even if only one part (like the database or a specific service) is under load.
Eventually, most monoliths hit growing pains. And that’s often the signal it’s time to rethink the architecture and explore alternatives.
Understanding microservices architecture
Rather than a single, unified unit, a microservices architecture consists of a collection of smaller, independently deployable services.
Earlier, we used the image of a big box to explain how monolithic architecture works. Microservices take a different path. Instead of one solid unit, we’re now looking at something more modular. Picture a set of smaller boxes — each one in charge of a specific task. On their own, they’re simple and focused. But together, they power the entire application and keep everything running smoothly.
It’s worth noting that microservices follow a more modern approach — and they’ve gained significant traction in recent years. Their compatibility with DevOps, automation, and CI/CD pipelines makes fast, reliable releases much easier to achieve.
For a deeper dive into the evolution of these architectural approaches, this paper offers a historical perspective—from early monoliths to the rise of microservices. It’s a great read if you’re looking to zoom out and explore the bigger picture.
Advantages of microservices vs monolithic
Next, let’s see the benefits it brings.
- Flexibility in tools and tech
As we’ve seen, monoliths usually stick to one language or framework, chosen early and hard to change later. Microservices open that up. Each team can use the tools that best fit their service, whether that’s a specific language, framework, or database. No need to force a one-size-fits-all stack. - Reduced dependencies and independent deployments
Monolithic systems often have tightly coupled components, making changes risky and coordination between teams necessary. Microservices are built to be loosely coupled. Services talk to each other through APIs but run on their own. That means updates, tests, and deployments can happen independently, without waiting on other teams or risking the whole system. - Smaller, safer changes
Because services are isolated, making a change in one won’t usually affect the others. That helps reduce the risk of bugs spreading and makes it easier to roll out updates with confidence. - Scaling only what’s needed
Scaling a monolith often means scaling the entire application. Microservices let you scale each part based on demand, so resources are used more efficiently (and costs stay under control)
Disadvantages of microservices
Microservices offer clear benefits, but they also introduce new challenges—especially when it comes to complexity.
- Increased operational complexity
Breaking an application into multiple services leads to more moving parts—more deployments, infrastructure, and potential points of failure. This demands strong observability, including monitoring, distributed logging, and robust error handling. What was once a single application becomes a system of interconnected components. - Testing and debugging hurdles
With microservices, it’s not just about making sure each service works on its own. You also have to test how they talk to each other — including APIs, data flow, and caching layers. When something breaks, debugging isn’t always straightforward. Tracing a single issue might mean jumping between services, logs, and tools just to find the root cause. - Cost and complexity upfront
Going microservices means investing in the right tooling, pipelines, and often shifting toward a DevOps mindset. That’s not always worth it early on. For small teams or young products, the overhead might slow you down more than help. - Organizational overhead
Microservices impact more than just architecture— they influence how teams operate. It’s a cultural shift toward autonomy and coordination.
So far, we’ve explored both microservices and monolithic architectures, looking at the benefits and drawbacks of each to understand which approach fits best — and when.
Before we get into making a decision, let’s take a look at one more option.
The hybrid approach: modular monoliths
Modular monoliths offer a middle ground. This approach keeps the simplicity of monolith architecture while allowing for future scalability. Best of both worlds? Let’s dig in.
So, what exactly is a modular monolith?
Modular monoliths are an evolution of the traditional monolith we just explored. While the entire application is still deployed as a single unit (just like in monolithic architecture), the code is organized into distinct modules, each responsible for a specific piece of functionality.
A modular monolith that’s been thoughtfully designed:
- Ensures low coupling and high cohesion between internal components
- Relies on well-defined interfaces for communication between modules
- Enables independent development and testing of each module
- Makes the codebase more manageable and scalable over time
- Avoids much of the operational complexity that comes with microservices
And perhaps most importantly, it can be gradually evolved into a microservices architecture if needed.
For teams taking this route, the Strangler Fig pattern offers a practical path forward: gradually replacing monolithic components with microservices by routing new functionality to separate services while retaining legacy features in the original system.
Real-world lessons from the trenches: making the transition (or not)
Let’s circle back to where we left off: which approach fits best? A few key questions arise after everything we’ve covered so far: When is monolithic architecture the better choice? When do microservices make more sense? And when is the right time to consider transitioning?
When to choose a monolithic architecture
Monolithic architecture remains a pragmatic choice in many scenarios, particularly in early-stage development. It allows for fast iteration, centralized code management, and lower operational overhead. For MVPs or products in early validation phases, speed, and simplicity often take precedence over distributed scalability.
Many engineering teams intentionally start with a monolith to reduce complexity and keep the deployment surface minimal, especially when working with small teams and limited infrastructure.
And sometimes… a monolith is the most effective long-term solution. Not every system needs to scale across multiple teams, services, or deployment zones. If the domain is well-bounded, the growth predictable, and the architecture modular enough, a monolith can remain robust and maintainable over time.
A hybrid approach
Modular monoliths strike a balance between simplicity and structure. This approach works especially well for teams that want the benefits of modularity — like separation of concerns and maintainability — without the added complexity of a fully distributed system. It’s a good fit for growing projects that aren’t ready for full microservices but need clearer boundaries.
When to consider microservices
Microservices tend to make the most sense when the different services you’re working on need to be developed, deployed, and/or scaled independently. This is often the case in dynamic environments where rapid iteration, continuous delivery, and architectural flexibility are essential.
Microservices are a strong fit when:
- Deployments and updates need to happen frequently and independently
- Development is distributed across multiple teams or time zone
- Different parts of the system require high scalability or variable resource allocation
- There’s a need to integrate diverse technologies, languages, or services
- Fault isolation and resilience are critical to maintaining uptime
- The system is built for cloud-native or containerized environments
- Services are structured around DDD principles or bounded contexts
From a different perspective, regulatory and compliance needs may also push organizations toward microservices, especially when systems need to isolate data, enforce audit trails, or maintain strict separation of responsibilities.
Which path to take?
Now that we've explored each option, it’s worth stepping back. Ultimately, it’s about choosing what aligns best with your current needs, technical maturity, and team structure. As mentioned at the beginning, there’s no universal answer — context matters.
Some scenarios tend to align naturally with certain architectures. For instance:
-Small team, MVP stage
-Monolith
-Growing team, early signs of complexity
-Modular Monolith
-Multiple teams
-Microservices
When choosing the right architecture, other aspects worth weighing include:
- Platform readiness — from deployment tooling to infrastructure and automation
- Architectural maturity — including how modular and decoupled the current system is
- Future needs — in terms of scalability, team growth, and feature velocity
Monoliths and microservices each bring their strengths. From our perspective, what matters most is how well your architecture serves the product, the team, and the road ahead.
At Nearsure, we collaborate with teams at all stages of architectural maturity, helping them make thoughtful decisions that support their long-term growth and goals.
If that sounds like the kind of work you’d like to be part of, we’re always looking for tech-savvy professionals to join our team. Check out our current roles.
