Open source has started energizing both industrial and academic research and development in electronic design automation (EDA) systems. By moving to open source, we can speed up our effort and work with others who are working toward the same goals, while reducing costs and improving end products. However, building an open-source project is much more than placing the codebase on the web. In this paper, we will talk about essential building blocks to create an impactful open-source project, including source repository, project landing page, documentation, and continuous integration. We will also cover the use of web-based frameworks to design a showcase project to bring community's attention. We will then share our experience in developing an open-source timing analyzer (OpenTimer) and a parallel task programming library (Cpp-Taskflow), both of which are being used in many industrial and academic EDA research projects.