Streamlit continuously expands its feature set to offer developers new capabilities with just a few lines of code. However, there comes a time when developers need to customize their applications to meet specific user needs. Whether it is modifying the user interface or providing a tailored user experience, Streamlit allows developers to create custom components as needed. Moreover, Streamlit supports the use of ReactJS to build components that can either function as a live web server or be deployed with production-ready code. In this chapter, we will guide you through the process of creating custom Streamlit components, integrating them into a Pythonic context, and sharing them with the broader community.