Node.js Framework: Express.js, Koa.js or Sails.js?

User interface


Yuliya Melnik, technical writer at Cleveroad discusses the challenges of selecting a Node.js framework and provides an overview of three frequently used frameworks: Express.js, Koa.js, and Sails.js.

Selecting the perfect Node.js framework poses a daunting challenge. With many options at your disposal, sifting through them all to find the best fit can prove quite arduous. This comprehensive piece aims to shed light on three frequently employed Node.js frameworks, namely Express.js, Koa.js, and Sails.js. By delving into their unique attributes, strengths, and drawbacks, we aim to aid you in identifying the ideal choice for your specific project requirements.


MVC frameworks have their foundation in the Model layer, the repository for the application’s business logic and data. It houses most of your back-end code, resembling a database containing objects and their interactions. Moving on to the View layer, you’ll find all the formatting and layouts responsible for presenting data on the user interface. Customization of the exposed portions of the Model can also be done from this layer. Finally, the Controller acts as the intermediary between these two layers, facilitating communication by handling requests from one and conveying updates to the other. It acts as a bridge that manages input/output between user actions at the View level and corresponding changes within the Model.

User interface

In most cases, MVC frameworks are ideal for enterprise-grade applications that require more rigid control over systems infrastructure. Such implementations provide upfront support through their extensive APIs but can often be less flexible than their lightweight counterparts, such as middleware-based servers, which tend to allow for faster development cycles due to fewer barriers when implementing change. Ultimately, selecting a Node MVC framework comes down to needs assessment, weighing both flexibility and control when assessing technical requirements surrounding development timeframes.


Middleware plays a crucial role in Node.js web development, providing developers with a seamless way to imbue their applications with extra functionalities without resorting to writing new code from scratch. The mechanism operates by cleverly stepping in between client and server requests, executing a series of operations (like authentication or request validation) before forwarding them along their intended path. The flexibility of middleware renders it highly advantageous for tailoring web applications precisely to one’s requirements.

By employing the appropriate configurations, developers can effortlessly integrate supplementary security measures, data validation mechanisms, and an array of other features into their projects, all while sidestepping the need to create supplementary code.

Client Middleware

Regarding middleware utilization, the go-to choice for many developers is Express.js. This particular framework comes equipped with many pre-built middleware functions, saving developers the hassle of crafting their own code. However, should the need arise for more specialized functionalities beyond what Express provides, developers always have the option to craft their own custom middleware. Notably, middleware finds its application not only in Express.js but also in other frameworks such as Koa.js and Sails.js, amplifying its potency as an indispensable tool in the Node developer’s toolkit.


Express.js stands as the ultimate Node.js framework, surpassing all others in the industry with the highest number of GitHub stars. Its exceptional speed, robustness, and seamless support for asynchronous programming make it the perfect choice for crafting a wide range of web applications—single-page, multi-page, or hybrid. Additionally, Express ingeniously amalgamates browser-specific APIs, typically unavailable in Node.js, with API frameworks, offering users unparalleled flexibility in generating dynamic content. The result is an impressively swift client-server interaction, capitalizing on the unique single-threaded structure associated with Node.

Express Pros and Cons

Furthermore, Express boasts many capabilities that facilitate swift and effective server-side development. Among these are remarkably extensive test coverage and many template engines catering to diverse file organization and database access requirements. Streamlining content negotiation through URLs and the HTTP protocol becomes a breeze when employing Express, given its remarkable capacity for seamlessly integrating back ends with browsers for efficient file storage functionality. In summary, Express provides extensive features, positioning it as the top preference for developers seeking a nimble and potent environment to embark on their projects.


Koa pros and cons

Koa.js is a lightweight Node.js framework for web app and API development. It uses JavaScript generators, making the code shorter. Koa allows easy control of the request-response cycle without explicit callbacks. Unlike other frameworks, it doesn’t come with built-in templating or routing tools, giving developers more freedom to customize their apps.

Due to its size and structure, Koa works well for startups with fast development cycles and lower costs. However, it may not be suitable for large corporate projects.


SailsJS is a cutting-edge, data-driven MVC framework, giving developers an optimal foundation for crafting personalized web applications. Its compatibility with all types of databases facilitates smooth integration with various JavaScript frameworks, ensuring seamless and dynamic applications. Bearing a solid resemblance to Ruby on Rails regarding the MVC architecture, SailsJS also provides innovative code-reduction techniques, enabling users to harness various NPM modules. Consequently, SailsJS showcases remarkable flexibility and adaptability to meet the ever-evolving trends and demands of the market.

Sails - pros and cons

Sails is known as a frontend-agnostic-backend platform because it doesn’t rely on any specific frontend technology. This gives developers more flexibility in their work. It uses Express to handle HTTP requests and Socket.io for efficient WebSocket communication, making it great for building real-time web apps and single-page applications. Sails simplifies custom application development, allowing developers to focus on creative ideas and achieve successful projects quickly.


As developers search for an appropriate web application framework, they must carefully assess several crucial elements. Initially, a thorough evaluation of each framework’s unique features becomes imperative to ascertain the one that strikes the perfect equilibrium between functionality and scalability for their specific application. Diverse frameworks may demonstrate varying degrees of support for APIs or libraries and exhibit distinct performance levels under particular workloads. By comprehending the disparities in user interfaces, development cycles, and extensibility, informed choices can be made to determine the most fitting framework for a particular app.

Second, you should hire node.js developers who can precisely achieve scalability and performance when selecting a framework. Smaller applications may not need to worry too much about those factors. Still, larger applications or ones expecting high traffic levels should look for frameworks that have been optimized for those purposes. User feedback from existing users is also worth considering; understanding how the framework behaves in real-world usage scenarios can give valuable insights into potential strengths or weaknesses under specific load types and demands. All this information will ensure that developers make an informed decision when picking the proper web app framework for their project.


Selecting a Node.js framework for a project depends on several factors influencing the decision. These factors include the project’s intricacy, customization requirements, and user-friendliness. If the project is relatively straightforward and doesn’t require extensive customization, Express.js can be an excellent choice. On the other hand, developers may find Koa.js and Sails.js more appealing as they offer advanced features and greater flexibility to tailor the development process to specific needs. Developers can confidently determine the most suitable framework for their project by thoughtfully weighing these aspects alongside user feedback.


Yuliya Melnik is a technical writer at Cleveroad, a web and mobile application development company in Ukraine. She is passionate about innovative technologies that make the world a better place and loves creating content that evokes vivid emotions.



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