In recent years, microservices have been the center of attention, but that doesn’t mean monoliths are obsolete. In fact, monolithic architectures are still a valid, often strategic choice for many projects.
🧱 What is a monolith?
A monolith is a software application where all the functionality is built into a single codebase and deployed as a single unit.
That means:
- All modules (auth, payments, product catalog, UI) live in the same repo.
- The backend, frontend (in some cases), and business logic run together.
- There’s one deployment pipeline and one runtime.
It’s the traditional way software has been built, and it’s still very common, especially in startups, internal tools, and even large platforms.
🧭 Monolith vs microservices
| Feature | Monolith | Microservices |
| Codebase | Single shared codebase | Multiple independent repos/services |
| Deployment | One artifact | Many deployments |
| Data layer | Often shared | Separate per service |
| Scaling | Whole app scales together | Independent service scaling |
| Team structure | Centralized | Decentralized teams |
| Complexity (infra/devops) | Lower | Higher |
✅ Benefits of a monolith
- Simplicity: Easy to develop, test, and deploy, especially in early stages.
- Less overhead: Fewer moving parts (e.g., no service discovery, API gateways).
- Easier debugging: One place to trace issues; local dev is straightforward.
- Tighter integration: Modules can share logic, models, and utilities directly.
- Faster to build: Less boilerplate, no network overhead between modules.
⚠️ Challenges of a monolith
- Harder to scale teams: Conflicts increase when many developers touch the same codebase.
- Deployment bottlenecks: A small change requires redeploying the whole app.
- Tightly coupled modules: Refactoring becomes harder as dependencies grow.
- Slower CI/CD: One test or build failure can block unrelated features.
- Tech lock-in: Harder to experiment with new languages or frameworks in parts of the app.
🛠️ When to use a monolith
Monoliths are a great choice when:
- You’re building a new product or MVP.
- You have a small team or solo devs.
- You want to optimize for speed, not scalability (yet).
- You don’t need independent service scaling.
- You’re focusing on domain complexity, not infra complexity.
Many successful companies start with a monolith and move to microservices only when necessary (usually due to scaling teams, not code).
🔄 Monolith ≠ bad
Don’t fall into the trap of thinking monoliths are outdated or inferior.
Modern tools like:
- Modular monoliths (well-separated domains in one codebase)
- Clean architecture / hexagonal architecture
- Monorepos with feature flags and modular builds
…allow teams to scale cleanly inside a monolith.
It’s not about monolith vs microservices, it’s about the right tool at the right time.
🧠 Conclusion
Monolithic architecture is still highly relevant in today’s software landscape. While microservices offer powerful scaling patterns, monoliths are simpler, faster to build, and easier to manage especially for small to mid-sized teams and products.
If you're starting a project, a monolith is often the right move. You can always extract services later when there's a clear need, not just because it’s trendy.