Gitea is a forge software package for hosting software development version control using Git as well as other collaborative features like bug tracking, code review, continuous integration, kanban boards, tickets, and wikis. It supports self-hosting but also provides a free public first-party instance
Mattermost is an open-source, self-hostable online chat service with file sharing, search, and integrations. It is designed as an internal chat for organisations and companies, and mostly markets itself as an open-source alternative to Slack and Microsoft Teams
Nextcloud is a suite of client-server software for creating and using file hosting services. Nextcloud provides functionality similar to Dropbox, Office 365 or Google Drive when used with integrated office suites Collabora Online or OnlyOffice. It can be hosted in the cloud or on-premises
Wolweb is a web interface for sending Wake-on-lan (magic packet)
Portainer is a container management software application to deploy, troubleshoot, and secure applications across cloud, datacenter, and Industrial IoT use cases
Prometheus is a free software application used for event monitoring and alerting. It records metrics in a time series database built using an HTTP pull model, with flexible queries and real-time alerting
Grafana is a multi-platform open source analytics and interactive visualization web application. It provides charts, graphs, and alerts for the web when connected to supported data sources