Software

Online appointment scheduling system. ([Demo](https://app.cal.com/bailey), [Source Code](https://github.com/calcom/cal.com))

Allows your customers to book appointments with you via the web. ([Demo](https://demo.easyappointments.org/), [Source Code](https://github.com/alextselegidis/easyappointments))

Event management and ticketing platform for conferences, concerts, and more. Offering customizable event pages and embeddable ticket widgets. ([Demo](https://demo.hi.events/event/1/dog-conf-2030), [Source Code](https://github.com/HiEventsDev/hi.events))

Resource scheduling solution offering a flexible, mobile-friendly, and extensible interface for organizations to manage resource reservations. ([Demo](https://librebooking-demo.fly.dev/), [Source Code](https://github.com/LibreBooking/librebooking))

Customizable and intuitive web-based hotel reservation system and a booking engine. ([Demo](https://demo.qloapps.com/), [Source Code](https://github.com/Qloapps/QloApps))

Create polls to vote on dates and times (alternative to Doodle). ([Demo](https://app.rallly.co), [Source Code](https://github.com/lukevella/rallly))

Webbased app to book seats, desks and rooms for offices. ([Source Code](https://github.com/seatsurfing/seatsurfing))

Create bunches of links to share with your learners or colleagues. ([Demo](https://ladigitale.dev/digibunch/#/b/5f67b12092b60), [Source Code](https://codeberg.org/ladigitale/digibunch))

Host your own Firefox accounts server. ([Source Code](https://github.com/mozilla/fxa))

Bookmark manager with a modern UI, automatic content & metadata extraction, categorization, filtering, and more. It has fully documented REST API, and Docker image for easy deployment. ([Source Code](https://github.com/goniszewski/grimoire))

Bookmark-everything app with a touch of AI for the data hoarders out there. ([Demo](https://try.karakeep.app/signin), [Source Code](https://github.com/karakeep-app/karakeep))

Bookmark archive with automatic backups to the Internet Archive, link monitoring, and a full REST API. Installation is done via Docker, or as a simple PHP application. ([Demo](https://demo.linkace.org/guest/links), [Source Code](https://github.com/Kovah/LinkAce/))

Minimal bookmark management with a fast and clean UI. Simple installation through Docker and can run on your Raspberry Pi. ([Demo](https://demo.linkding.link/login/), [Source Code](https://github.com/sissbruecker/linkding))

Bookmark and archive manager to store your useful links. ([Source Code](https://github.com/linkwarden/linkwarden))

Save the precious readable content of web pages you like and want to keep forever. See it as a bookmark manager and a read later tool. ([Source Code](https://codeberg.org/readeck/readeck), [Clients](https://codeberg.org/readeck/browser-extension))

Sync and manage your browser bookmarks from Edge, Firefox and Chromium. ([Clients](https://codeberg.org/Offerel/SyncMarks-Extension))

Lightweight CalDAV and CardDAV server based on sabre/dav. ([Source Code](https://github.com/sabre-io/Baikal))

Server for calendar sharing (CalDAV) that uses a PostgreSQL database as a data store. ([Source Code](https://gitlab.com/davical-project/davical))

Manage my Damn Life (MMDL) is a self-hosted front end for managing your CalDAV tasks and calendars. ([Source Code](https://github.com/intri-in/manage-my-damn-life-nextjs))

Simple calendar and contact server with extremely low administrative overhead. ([Source Code](https://github.com/Kozea/Radicale))

Open source CardDAV, CalDAV, and WebDAV framework and server. ([Source Code](https://github.com/sabre-io/dav))

Realtime server for reliable two-way communication over WebSockets, Server-sent events, etc. ([Demo](https://demo.anycable.io), [Source Code](https://github.com/anycable/anycable))

Language-agnostic real-time messaging (Websocket or SockJS) server. ([Demo](https://github.com/centrifugal/centrifugo#demo), [Source Code](https://github.com/centrifugal/centrifugo))

Peer-to-peer chat app that is serverless, decentralized, and ephemeral. ([Source Code](https://github.com/jeremyckahn/chitchatter))