Building an open-source community with hundreds of people from all over the world who come together to develop highly complex software systems or collaborate on cutting-edge research is no easy task. It requires communication tools that support transparency in decision making, asynchronous collaboration, and efficient use of community members’ time. We know there are key (and overlapping) groups of people who make up a vibrant community: project leaders, core and casual contributors, new and experienced folks, and end users. Looking at these categories, we can define shared and specific communication needs for working and collaborating together. Zulip has made key design choices and invested in developing many features to address these particular needs. Let's dive in and explore together the unique characteristics of Zulip and how they can (and have) impacted collaboration and communication in FOSS and research communities.