DAViCal CalDAV & CardDAV Server

OpenGroupware.org   (Compare Project)

Very Low Activity

Mostly written in Objective-C

License: LGPL

Buni Meldware Communication Suite   (Compare Project)

Activity Not Available

Mostly written in Java

License: LGPL

Fin Calendar Server   (Compare Project)

Activity Not Available

Mostly written in Java

License: LGPL

Calendar and Contacts Server   (Compare Project)

High Activity

Mostly written in Python

License: Apache-2.0

Mozilla Calendar   (Compare Project)

Very High Activity

Mostly written in C++

License: GPL-2.0+, LGPL, MPL-1.1

eGroupware   (Compare Project)

Very High Activity

Mostly written in PHP

License: GPL-2.0+

citadel   (Compare Project)

High Activity

Mostly written in C

License: GPL-3.0

Bedework Enterprise Calendar   (Compare Project)

Moderate Activity

Mostly written in XSL Transformation

License: BSD-3-Clause

SOGo   (Compare Project)

High Activity

Mostly written in Objective-C

License: GPL-2.0+

WebCalendar   (Compare Project)

Low Activity

Mostly written in PHP

License: AFL-3.0

OpenVPN   (Compare Project)

High Activity

Mostly written in C

License: GPL-2.0+

BIND (Berkeley Internet Name Domain)   (Compare Project)

Activity Not Available

License: ISC

cURL   (Compare Project)

Very High Activity

Mostly written in C

License: MIT

Common Unix Printing System (CUPS)   (Compare Project)

Activity Not Available

Mostly written in C

License: GPL-2.0+

Wireshark   (Compare Project)

Very High Activity

Mostly written in C

License: GPL-2.0+

ImageMagick   (Compare Project)

Very High Activity

Mostly written in C

License: Apache-2.0

Inkscape   (Compare Project)

High Activity

Mostly written in C++

License: GPL-2.0+

rsync   (Compare Project)

Very Low Activity

Mostly written in C

License: GPL-2.0+

PostgreSQL Database Server   (Compare Project)

Very High Activity

Mostly written in C

License: PostgreSQL

Debian GNU/Linux   (Compare Project)

Very High Activity

Mostly written in C

License: Distributable