What does Sitecore's JSS allow developers to utilize alongside Sitecore's capabilities?

Sitecore's JSS (JavaScript Services) is designed to enable developers to leverage modern web technologies and frameworks when building applications that interact with Sitecore. This is significant because it allows developers to adopt contemporary development practices, such as using React, Angular, or Vue.js, which align with current trends in the web development landscape.

By integrating these frameworks, Sitecore JSS enhances the flexibility and performance of applications, empowering developers to create dynamic user experiences while still benefiting from Sitecore’s robust content management features. This combination fosters a more responsive and engaging front-end experience, as modern frameworks offer efficient state management and optimized rendering capabilities.

The other options do not encapsulate the primary advantage of using JSS within Sitecore. Server-side rendering can be a part of JSS applications but is not the central feature. Pre-built templates limit the use of JSS to only those templates, and legacy languages do not align with the modern approach the JSS supports. Thus, the focus on modern technologies and frameworks is what accurately represents the capabilities JSS allows developers to utilize alongside Sitecore.