The question “Monolith or microservices?” is often discussed as a matter of faith. The truth is more pragmatic: Both architectures have their place – what matters are your specific requirements, your team structure, and your operational maturity. In this article, we show when each architecture makes sense and how you can manage the transition.
A monolith is a single, cohesive application: All functions are united in one codebase, deployed together, and share database and infrastructure. Microservices, on the other hand, consist of many small, independent services, each fulfilling a specific function and communicating via APIs.
Key Takeaway
Microservices are not an upgrade “per se”. When teams, observability, deployment automation, and domain boundaries are properly set up, microservices can accelerate delivery. Without these foundations, they quickly become more expensive than a well-structured monolith.
When a Monolith Is Often the Right Choice
A monolith is by no means “outdated” – it is often the more efficient choice, especially in early project phases. The simpler structure means less infrastructure overhead, easier debugging, and faster iteration.
- Product/domain is still evolving (scope changes frequently) – refactoring is easier
- One team handles most of the delivery – fast iteration more important than decoupling
- Operations/DevOps maturity is being built – fewer moving parts mean less complexity
- Transactional consistency is critical – ACID transactions across module boundaries
- Budget and time are limited – monoliths have lower initial overhead
When Microservices Make Sense
Microservices deliver their value when the complexity of the organization exceeds the complexity of the technology. When multiple teams need to deliver independently, a monolith becomes a bottleneck.
- Multiple teams need to deliver independently (ownership per domain) – Conway's Law applies
- Scaling is domain-specific (one part needs to scale much more than the rest)
- High requirements for availability, SLAs, audit trails – isolation reduces blast radius
- Different technology requirements per domain – polyglot development possible
- DevOps maturity is established – CI/CD, monitoring, service mesh are in place
Pragmatic Path: Modular Monolith → Decoupling
The often best approach is not “monolith or microservices”, but decoupling in stages: First clear modules/bounded contexts, contracts, tests, and observability – then extract individual domains (strangler pattern).
A modular monolith is a middle ground: The application remains a single unit but is internally divided into clear modules with defined boundaries. Each module has its own responsibility, communicates through defined interfaces, and could later be deployed independently.
This way, you avoid big-bang migration and reduce risk while delivery speed increases. The transition to microservices becomes an evolutionary development instead of a risky large-scale project.
Avoiding Common Pitfalls
Monolith Pitfalls
- Big Ball of Mud without clear module boundaries
- Missing tests make refactoring difficult
- Deployment fear due to lack of automation
Microservices Pitfalls
- Distributed monolith due to poor service boundaries
- Operational overhead without appropriate tools
- Data inconsistency due to missing saga patterns
Recommended next steps
Related Services & Solutions
For architecture and modernization projects, these entry points are usually the most relevant: