Serverless vs. Microservices: What to Choose for Your Project

When it comes to software development, it is paramount to choose a particular framework as the foundation for the development process. While there are various options, most companies engaging in software development stick to serverless or microservices architectures. Allied Market Research indicates the global microservices architecture market size will reach $8 billion by 2026. It shows an 18% annual growth rate from 2019 to 2026. The global serverless architecture market value is expected to reach $21 billion by 2025, representing a 22% Compound Annual Growth Rate (CAGR). 

The evidence shows that the serverless framework has a lead. Yet, each particular approach has pros and cons, and when used in proper conditions, they can help deliver your projects with minimum hiccups. Further, we explore serverless and microservices phenomena and investigate them from perspectives of benefits, drawbacks, and use cases to suggest which architecture meets your project's demands. 

What is Serverless?

One might anticipate the definition of serverless as being connected to something that does not have any relation to a server. However, such a vision is misleading. In reality, serverless means a type of architecture that does not involve investing or maintaining any physical hardware. In turn, companies directly rely on third parties to offer management or maintenance to the physical infrastructure, which often includes aspects like storage, network, and a server. Considering serverless architecture examples, consider Microsoft Azure, AWS Lambda, and Google Cloud Platform. 

When it comes to different angles on serverless architecture, one should mention two particular perspectives:

1. Function as a Service (FaaS). This model grants developers an opportunity to use various serverless functions without the need to consider different system requirements and backend infrastructure. 
2. Backend as a Service (BaaS). This model presumes the entire backend of a system to be managed independently and offered as a service by a dedicated third party. 

With these two models in mind, the serverless architecture is executed in a particular sequence. 

• Notably, everything starts with serverless functions, when developers write lines of code that will do a certain task within the app. Usually, it is a short-term process that relies on the factor of simplicity. Importantly, one particular function cannot perform various actions. 
• The second step is about the serverless event. It is when developers assign certain events to particular functions. If the conditions are properly met, the specific serverless function is activated. 
• The third step is about the serverless trigger. It happens when a particular event triggers a certain function. The trigger occurs when a user interacts with an app, clicks a button, presses a specific key, or touches a screen at a pre-defined interface. 
• The fourth stage is serverless execution. It takes place when the functions start running after the execution process is triggered.
• The final phase is about serverless output. It is the moment when users get updates on their side of the application. Usually, such updates are presented in a certain form of output.

The serverless architecture ensures a third party covers the physical architecture involved in the software development process. There are two models within the serverless environment, as well as it includes a five-step execution process.  

Benefits of a serverless framework

Choosing a particular architecture often depends on weighing its benefits and drawbacks. Within such a scope, the advantages of the serverless architecture are the following:

• Simple deployment. With serverless architecture, developers do not need to worry about any aspects of backend functionality. It anticipates less time for building, upgrading, and maintaining the entire underlying infrastructure. Developers only need to proper code and release it on a particular server. All these factors make the deployment process as a whole far easier. 
• Saving costs. While a third party handles aspects like hardware and internal logic, you do not need to pay for internal processes. There are also reduced costs in terms of hiring server experts. These aspects boost the cost-efficiency of the deployment process.
• Easier scalability. If needed, one can immediately increase computing power and storage capacity with serverless architecture. It makes scalability easier, and grants access to immense serverless computing resources. 
• Higher flexibility. Serverless functions offer instruments for the quick release of new features. It is done by adding new functions along with triggers. Moreover, developers can reuse the code and apply pre-made templates to increase the deployment process. 
• Reduced latency. Serverless architecture presumes vendors' servers maintain the infrastructure in the cloud, which means all across the globe. As a result, when there is a user request, the provider automatically assigns a server callback from the server closest to a particular user. This process drastically reduces latency. 
• Third-party responsibility. Within a serverless environment, all the responsibilities linked to the management of computing resources lie on the vendor’s shoulders. 

These benefits make serverless computing appealing to many companies. Serverless architecture is often the best option when the deployment process includes a complex backend process.  

Drawbacks of a serverless framework

Like with any framework on the market, there are particular downsides included. The same is true for serverless architecture. The following are the disadvantages of serverless computing:

• Defining boundaries. It appears to be challenging to determine functions within a serverless environment. Each particular function should have a certain limited role. However, stretching internal logic too far across serverless functions make it difficult to update and change the architecture. 
• Function performance. Various serverless architectures have performance problems, the ones linked to the factor of function optimization. For instance, there is a notion of cold starts involved. It occurs when a serverless function is initiated after a period of inactivity. Restarting such a function can increase latency. Dealing with this type of function performance issue takes time and money. 
• Monitoring the process. One application can have multiple serverless functions involved. They are often short-lived as well as interact with various resources. Such a structure elevates the level of complexity and makes monitoring of requests across serverless environments complicated. 
• Commitment. Finally, the particular downside of a serverless environment is linked to the issues related to a long-term commitment with a specific vendor. Often, long-term contracts come with aspects that can change and are hard to anticipate, which increases the degree of uncertainty.

It is vital to consider the disadvantages mentioned above when you consider choosing serverless architecture. Now, when you get the gist of what serverless entails, let’s proceed to a second option — microservices. 

What are Microservices?

What is a microservice architecture? Microservices definition entails building autonomous elements interlinked with one another through Application Programming Interfaces (APIs). Every component within such an environment is coined as microservices. They execute one function or process at a time. What is more, particular containers act as stand-alone applications. Microservices are deployed within such containers. 

A microservice includes basic elements supporting its run-time. These include a database, a library, and a template. Usually, developers would break down the app’s features and functions into separate elements to retain the functionality and get a decentralized model. Later, these elements are defined, interlinked, and assigned to various developers' teams for further development and maintenance. Each microservice within the microservices architecture is developed and tested independently. Afterward, they are executed in isolated containers. In general, building using a microservices environment entails four stages:

1. The phase of decomposition that includes all the app’s features is to be broken down into smaller parts. At this stage, developers emphasized setting the functionality of a decentralized model. 
2. The second stage is about design. Establishing the core services of the framework is all about setting a connection between these services. At this point, you need to develop a hierarchy across services.
3. The third phase is development. After microservices mapping is up-and-running, the development term starts building services. In such a case, everyone on the team understands how components and elements correlate to a single system. The whole team will be broken down into smaller teams, each handling a particular microservice.
4. The final stage is about deployment. At this point, microservices are deployed in containers or as FaaS within the serverless architecture. 

At this point, microservices allow handling different smaller components of the infrastructure while preserving the functionality of the whole. It shows a difference between monolithic and microservices. While the former is built and deployed holistically, the latter are built and deployed as multiple small services and components that can be developed and scaled independently. 

Advantages of microservices architecture

Both serverless and microservices architectures have pros and cons. In such a context, microservices environments bring the following benefits:

• Decentralization. Each element within the microservices environment has a separate database. It is beneficial because if one microservice has some security issue or error, it won’t affect the other data stored. What is more, developers can employ various protective measures for different scenarios. 
• Smaller components. Each particular system within the infrastructure can be broken down into many smaller services. Developers can develop and test each one of them independently. It ensures that the entire architecture won’t be affected if one particular microservice is changed. 
• Riskless. The beauty of microservices is all about independence and decentralization. It entails low risks. Even if only one service fails, it can be immediately substituted by another service. Besides, developers are open to redistributing connections between servers to replace a failed service with a functioning one. 
• Better scalability. When it is time to scale, many companies appeal to microservices environments. It is done because the entire platform can be broken down and updated without adversely affecting the whole infrastructure. 
• Applicability. Microservices architecture is flexible in changing existing business logic and applying a broad range of technologies. 

The aspects mentioned above make microservices architecture appealing to companies that do not want to pause their platforms when bringing new updates and scaling. 

Disadvantages of microservices architecture

However, similar to serverless architecture, microservices environments have their hiccups. These are the drawbacks worth mentioning:

• Connection. Because multiple microservices are often involved in projects, it can be complicated to establish a stable relationship between them. This is why teams need to plan how to connect all the elements to transfer data from one location to another when dealing with the architecture. 
• Testing. There can be problems when you need to test all the microservices, both independently and on a broader scale. Testing many elements can be time-consuming. 
• Debugging. When you need to debug the system, it takes going through the logs in every given microservice, which can be a daunting task if many microservices are involved. 
• Security. Even though the microservices architecture is low-risk, there are security concerns involved. You need to pay attention to APIs because they can be vulnerable due to misconfigurations. 

There are certain drawbacks to microservices environments to keep in mind. Each one of them can slow down the development and deployment processes. 

Uses Cases for Serverless

Serverless architectures are low-cost and perfect for lightweight applications. That is why many startups choose serverless environments. In contrast, enterprises are warier of this tool because of the drawbacks mentioned earlier. However, when thinking about particular best-case scenarios for serverless architectures, the following should be considered:

• If you are building an app that entails variating traffic, appealing to a serverless environment is the best solution. This architecture allocates server resources automatically; it does not matter whether your app is completely idly or has spikes in traffic. All these parameters will be handled without you breaking a sweat. 
• Serverless environments are event-based and best for developing apps working with the Internet of Things. 
• To automate continuous integration and delivery, serverless architecture is the best option. Your developers can simply write down automatic testing or deployment algorithms as events and triggers. And the serverless architecture will do the rest. 
• Any projects that do not have a big budget and need to be deployed immediately are better off with a serverless environment. Besides, such projects often entail short-term functions, and the aspects of serverless architectures are beneficial.  

In a nutshell, serverless architecture is best for startups, namely because of its cost-efficiency, easy deployment, and integrations. You can combine serverless functions with various databases and API management tools. 

Uses Cases for Microservices

Microservices architecture is best for enterprises looking to manage apps and systems that are evolving, complex, and need regular scalability. The tool is perfect for app processing massive volumes of data, namely because you receive an opportunity to break down complex functions and maintain separate components without breaking the infrastructure. Keeping that in mind, there are particular microservices use cases to consider:

• The architecture is perfect for apps that need to be scaled up quickly. Microservices allow doing that without breaking the entire infrastructure. 
• Microservices architecture offers the most possibilities if you are developing apps that will be updated and changed regularly. Besides, microservices provide such an opportunity if the alterations need to be made in a short time. 
• When dealing with big data apps, it is better to use the microservices environment. The reason for such a choice stems from the nature of big data. It is a notion including one task at every stage, for instance, data collection, processing, and delivery. In such a context, microservices can handle each task within a big data environment. 
• When you have or build more than one app or software, microservices are the option to choose. Your developers can simply reuse teh code and save a massive amount of time for the entire development and deployment process. 

These are scenarios where microservices offer the most promises. Essentially, the architecture works with complex apps that need to be changed and updated regularly to maintain constant scaling. Besides, microservices architecture is perfect for companies working to build more than one app at the same time. 

Choosing Between Microservices vs. Serverless 

When choosing between serverless and microservices architecture, there are particular insights to mention. 

First and foremost, it all depends on the services you are looking for. For instance, microservices functions are best for long-term projects relying on the continuous performance of particular functions. In turn, serverless functions are not constant and even-triggered, and the environment cannot include more than one function. 

Second, you need to analyze your business goals and product scope. In such a case, if you want to save costs and have a quick deployment-to-market process, serverless architecture is the one to choose. In turn, microservices architecture is a good bet if cost is not a problem and you need to build complex and constantly evolving software. 

Finally, if you don’t know what particular framework to choose, there is a way out. Cloud providers like Amazon and Google found a bridge between two choices. How? They managed to transform microservices architecture to be developed as event-based functions while also stored within a third-party infrastructure. Yet, this model is still under development, and it is always best to choose serverless or microservices based on your particular needs and understanding of both. 

What Do Tech Unicorns Use?

At this point, serverless and microservices functions have particular pros and cons. One cannot say that one is better than the other per se. It all depends on business goals, product scope, budget, and the type of software developed. Naturally, some companies have chosen serverless options over microservices and vice versa.

Companies using microservices architecture

There are some massive names among companies employing microservices functions:

• Netflix. The company was among the first to employ microservices architecture. It is used to maintain massive data storage and keep the platform stable. Besides, microservices are coupled with algorithms allowing Netflix to monitor the popularity of certain movies and shows, and something is done to boost user experience.
• Amazon. In 2001 the company emerged as a monolith. Yet, it further experienced exponential growth and scalability. In 2021, the company moved to cloud-computing services releasing AWS. Essentially, microservices proved extremely beneficial for eCommerce because they allow tracking of user behaviors and the entire sales funnel. 
• Groupon. In 2012 the company looked for migration to microservices architecture. It looked for efficiency and the ability to manage massive numbers of coupons and data. The rapid growth of this business offered tremendous opportunities for the front and backend of their website, namely because of the increasing traffic and need to scale. 
• Uber. Similar to Amazon, Uber is a company that has experienced a massive degree of scaling. As a result, many new aspects emerged as a part of Uber’s business operations, requiring a new instrument to handle and monitor. Now, the company uses a microservices architecture to handle countless daily operations and has a highly optimized infrastructure. 
• Spotify. With more than 365 million active users, the platform must manage vast user requests and pressure on servers daily. The company entails more than nine dozen autonomous full-stack teams building and composing services. To address such a degree of complexity and scaling, microservices are the best fit. 

These companies proved to effective use microservices architecture. You can see that the companies on the list are behemoths, working with millions of users and handling vast volumes of data. 

Companies using serverless architecture

Companies using serverless functions are different from the ones using microservices. These are the following:

• Codepen. The company was launched in 212 as a source of knowledge for developers. The platform allows sharing of code within the developer community. Codepen uses serverless architecture to serve every given request fast and with the ability to handle additional traffic. 
• Zalora. The company is the leading fashion business in Asia. It has about 20 million clients. Zalora depends on serverless architecture to ensure a high-quality customer experience. When people shop via their website, the system needs to handle different traffic rates, and the serverless technology allows doing so.  
• Nordstrom. The company uses AWS. It relies on the smooth and efficient delivery of services. And serverless architecture grants such an opportunity through cloud services and third-party vendors. 
• MindMup. The company helps users create mind maps to use for better team management. Users can access almost unlimited numbers of mind map templates and can create and alter them online. To handle the traffic, serverless architecture is the best fit. 

Companies using serverless environments focus on handling traffic and offering the best user experience. These online platforms often allow clients to interact with products and services directly.

Key Takeaways

The journey has shown that microservices and serverless architecture offer particular benefits in certain conditions. There are pros and cons to both approaches. However, to choose the architecture meeting your needs, it is crucial to align your business goals and factors like budget and the need for scalability. The general trend dictates that massive companies that constantly evolve prefer microservices. They allow breaking down the infrastructure into smaller parts and handling them independently. In turn, companies that rely on additional traffic and look to create user experience rely on serverless architecture. Luckily, there is always an option, even if you don’t know what to pick.