Microservices vs Monolith: Which Architecture Should You Choose for a New Project?

When launching any digital product, choosing the right architecture plays a key role. We see this in practice every day: whether a business decides to build a system as a monolith or go straight for microservices directly impacts the time-to-market, scalability, and overall project budget. Monolithic architecture allows for a faster launch, lower costs at the initial stage, and the ability to test hypotheses without unnecessary complexity. Microservices architecture, on the other hand, provides flexibility and scalability once the product starts growing and needs to handle higher loads or be developed in parallel by multiple teams.

Our experience shows that making the right architectural decision from the very beginning helps avoid costly redesigns later, saving both time and resources. That’s why we always analyze the specifics of the business and the product before recommending the optimal solution. In this article, we’ll explore what microservices and monolithic architecture are, their pros and cons, how they affect budget and timelines, and which one is best suited for launching a project.

Monolithic architecture is an approach where all application logic is stored in a single codebase and deployed as one whole. Within such a system, all modules (for example, user management, payments, analytics) are tightly coupled and function as parts of one large block. Any change or update affects the entire project at once.

How It Works

A typical monolith can be represented as a three-layer system: interface → business logic → database.

• Interface (UI). Everything the user interacts with: web pages, mobile screens, admin panels. In a monolith, the UI is usually part of the same codebase: the server renders HTML/JSON, static resources are built and deployed together with the application, and routing and authentication go through shared middleware. This reduces the number of integration points and simplifies the setup of authentication and logging.
• Business logic (application layer). This is where the code for domain modules lives: users, orders, payments, reports. They are tightly connected and call each other through local methods (without network APIs). They share utilities such as validation, transactions, and caching, and run as a single process. For example, when a user places an order, the monolith’s controller calls the cart, payment, and notification services. The payment service processes the transaction, writes the data to the database, and returns the result – after which the user sees the “Order completed” page.
• Database (data layer). Typically, a monolith uses a single shared database or cluster. All tables and schemas are common, transactions cover multiple modules at once (for example, order and payment). Migrations and caching are also centralized, which ensures data consistency and reduces synchronization overhead.

Thus, a monolith operates as a single organism: interface, business logic, and database are tightly integrated and deployed together.

Key Advantages of Monoliths

• Simplified development – a single codebase, clear structure, fewer integration points.
• Faster launch – ideal for MVPs and startups where speed is critical.
• High performance – modules interact directly without network latency.
• Easier debugging – errors are easier to track within one application.

Disadvantages of Monoliths

• Scaling limitations – load can only be distributed across the entire system, not individual modules.
• Module dependency – changes in one block may cause errors in others.
• Technology lock-in – the entire team works on one stack, and introducing new solutions requires reworking the whole application.
• Complex updates – even small changes require rebuilding and redeploying the entire project.

Microservices architecture is an approach to building applications as a collection of independent modules. Simply put, a microservice is a separate component responsible for a specific task: authentication, payments, product catalog, notifications, and so on. In other words, what is a microservice? It’s a small, standalone block that can be developed, tested, and deployed independently from other parts of the system.

All microservices interact with each other through standardized interfaces (most often APIs or message queues). Unlike monoliths, there is no single codebase here: each module evolves separately, can use its own technology stack, and be released to production independently.

How Microservices Work

A typical microservices-based application can be represented as a chain of independent modules connected through APIs:

• Interface (UI). The user interacts with the frontend – for example, placing an order. The frontend doesn’t contain all the business logic itself but instead sends a request to the appropriate subsystem.
• Business logic services. Each module functions as a separate application, with its own programming language, database, and deployment pipeline.
  • The cart service checks the contents of the order.
  • The payment service validates the data and processes the transaction.
  • The notification service sends an email or push notification to the client.
• Databases. Often, each functional block has its own database (for example, PostgreSQL for orders, MongoDB for the catalog, Redis for caching). This reduces coupling and makes it possible to scale only the bottleneck.

Example scenario:

1. A user places an order.
2. The frontend calls the cart service → the cart checks the items.
3. The cart service calls the payment service via API → the payment is processed.
4. The payment service notifies the orders and notifications modules.
5. The user receives a message: “Order completed.”

Each software element performs its own function, and the entire process works like a well-orchestrated system.

Advantages of Microservices

• Flexibility. Each block can be modified and updated independently of the others.
• Independent scaling. As load increases, only the payment or search subsystem can be scaled without affecting the entire application.
• Freedom of technology choice. Teams can use different languages and databases for different parts of the system.
• Team distribution. Each team owns its own module, making parallel development easier.
• Fault tolerance. If one service fails (e.g., notifications), the rest of the application keeps running.

Disadvantages of Microservices

• Complex design. It’s critical to define service boundaries correctly, or duplication and chaos may occur.
• Harder debugging. Errors can be “spread” across the chain of services, requiring centralized logging, tracing, and monitoring.
• High DevOps demands. For everything to run smoothly, CI/CD pipelines, containerization (Docker/Kubernetes), load balancers, and service meshes are needed.
• Network overhead. Where a monolith executes a method in memory, microservices communicate through network calls, adding latency.
• Higher development costs compared to monoliths. Investment is needed in infrastructure, DevOps practices, and maintenance of a distributed system.

Why Monoliths Are Cheaper at the Start

Monolithic architecture typically requires fewer resources and lower investment in the early stages.

• Simpler infrastructure. One server or container is usually enough for the entire application.
• Fewer integrations. All modules operate within a single codebase, with no need for complex API gateways, message brokers, or separate pipelines.
• Faster development. The team can focus on business logic and the interface instead of configuring infrastructure.

This is why monoliths are often chosen for MVPs and pilot versions of products: they allow businesses to quickly validate hypotheses without unnecessary costs. You can learn more about this in our IT project cost calculator.

When Microservices Are Justified by Budget

Microservices require greater investment in development and DevOps: separate pipelines, containerization, load balancers, monitoring systems, and service-to-service communication logic. However, this approach pays off when:

• High load. The application must reliably serve thousands of users simultaneously.
• Long-term, large-scale projects. The system will grow and evolve for years to come.
• Complex business processes. For example, multiple parallel domains (logistics, finance, CRM, analytics) that are easier to separate into services and scale independently.
• Large teams. Multiple development groups can work on different services in parallel without code conflicts.

In short, architecture directly impacts the budget: monoliths provide savings and speed at launch, while microservices provide resilience and efficiency during growth.

Scaling in Monoliths

In monolithic architecture, scalability is limited:

• Vertical scaling. Increasing the resources of a single server (CPU, RAM) to handle higher loads. However, this approach hits a ceiling defined by the hardware’s maximum capacity.
• Horizontal scaling. Running multiple copies of the entire application. This works, but it’s inefficient: if only the analytics module is overloaded, the whole monolith must still be scaled.

Monolith scaling usually happens as a whole – either by vertical server upgrades or by launching full application copies. That said, there are partial solutions: some components can be scaled through caching, sharding, or splitting off processes into standalone modules.

Scaling in Microservices

Microservices architecture is designed for flexible scaling from the ground up:

• Each service can be deployed in as many copies as needed, independently of others.
• Load is distributed only on the bottleneck – for example, the search or payment service.
• Teams can develop individual services in parallel, adding new functionality without affecting the rest of the system.

This approach allows businesses to use resources more efficiently and grow without hard limits. In our projects, we use software design that takes into account both a fast monolithic start and the gradual extraction of services later.

A Hybrid Approach: From Monolith to Microservices

In practice, we often apply the strategy “fast start with a monolith → gradual transition to microservices.”

• At launch, a monolith is built: it’s cheaper, faster to develop, and well-suited for MVPs.
• As load increases and business processes become more complex, individual modules – such as payments or analytics – are extracted into standalone services.
• The result is a hybrid system: the core remains monolithic, while high-load modules function as microservices.

This approach enables businesses to enter the market faster while also preparing the architecture for future scalability.

The choice between a monolith and microservices depends on several key factors. In practice, we always evaluate a project through the lens of budget, timelines, and business strategy.

• Budget. If resources are limited and minimizing infrastructure and DevOps costs is critical, teams usually start with a monolith. If the project is designed for the long term and backed by a substantial budget, it makes sense to build microservices from the start.
• Time-to-market. When you need to quickly test a hypothesis and launch a project, monoliths offer speed advantages. For products where stability and independent module development are important from day one, microservices are a better fit.
• Expected load. If the system is designed for a limited user flow at launch, a monolith will be sufficient. If heavy load is expected (for example, a marketplace or fintech service), microservices are justified from the beginning.
• Strategic business plans. When the product is envisioned as a long-term ecosystem covering multiple domains (CRM, warehouse, finance, mobile app), microservices enable an architecture ready for expansion.

That’s why we never give a universal answer like “monoliths are better” or “microservices are better.” Architecture must be chosen based on the specific project: monoliths for a fast start, microservices for sustainable growth.

There is no single “right” choice in architecture. Monoliths and microservices are two different approaches, and the decision between them always depends on business goals and context.

• Monoliths deliver speed to market and budget efficiency at launch, making it possible to quickly test hypotheses and release an MVP.
• Microservices provide flexibility, independent module development, and scalability – critical for long-term, high-load projects.

An optimal strategy often lies in starting with a simple monolith and gradually extracting services as the product grows. This way, you combine the strengths of both approaches.

Our team helps businesses choose the right architecture for their specific use case – from lightweight MVPs to large-scale enterprise systems. Reach out to us for custom software development, and we’ll ensure your product grows without limitations.