@strapi/core is a powerful and flexible core package of Strapi, an open-source headless content management system (CMS) designed for building APIs and managing content easily. Strapi allows developers to create customizable APIs quickly, making it an excellent choice for projects that require a robust backend without the overhead of traditional CMS platforms. The core package provides essential functionalities for setting up and managing the Strapi application, including routing, middleware, and plugin support.

While Strapi is a strong option for building headless CMS solutions, there are several alternatives in the Node.js ecosystem that serve similar purposes. Here are a few noteworthy alternatives:

• @nestjs/core is the core package of NestJS, a progressive Node.js framework for building efficient and scalable server-side applications. NestJS leverages TypeScript and incorporates modern programming paradigms, making it suitable for building complex applications. If you are looking for a structured and modular approach to building APIs, NestJS is a great choice, especially for enterprise-level applications.
• @strapi/strapi is the complete Strapi package that includes the core functionalities along with additional features for building and managing APIs. It provides a user-friendly interface for content management and is ideal for developers who want a comprehensive solution for their backend needs without having to build everything from scratch.
• express is one of the most popular web frameworks for Node.js. It provides a minimal and flexible set of features for building web applications and APIs. Express is known for its simplicity and ease of use, making it a go-to choice for many developers. If you prefer a lightweight framework that allows for maximum customization, Express is an excellent option.
• fastify is a fast and low-overhead web framework for Node.js, designed for building high-performance applications and APIs. It emphasizes speed and efficiency, making it suitable for applications that require quick response times. Fastify also supports a rich plugin architecture, allowing developers to extend its functionalities easily.
• hapi is another robust framework for building applications and services in Node.js. It is known for its powerful plugin system and configuration-driven approach, which makes it suitable for building large-scale applications. Hapi provides a rich set of features out of the box, making it a solid choice for developers who need a comprehensive framework.
• koa is a lightweight and expressive middleware framework for Node.js, created by the same team behind Express. Koa aims to be a smaller, more expressive, and more robust foundation for web applications and APIs. If you prefer a more modern approach to middleware and want to leverage async/await for better control flow, Koa is a great option.
• sails is a framework for building Node.js applications that follows the MVC (Model-View-Controller) pattern. It is designed for building data-driven APIs and comes with built-in support for WebSockets, making it suitable for real-time applications. If you are looking for a framework that provides a full-featured architecture out of the box, Sails is worth considering.

To compare these packages further, check out the following link: Comparing @nestjs/core vs @strapi/core vs @strapi/strapi vs express vs fastify vs hapi vs koa vs sails.