Tools to accurately transfer 3-D geometry between applications

https://www.rhino3d.com/opennurbs

Implementation of the PGM reliable multicast protocol

https://code.google.com/p/openpgm/

Software to control a multitude of (a)RGB devices

https://openrgb.org

Implementation of rsync with a BSD (ISC) license

https://github.com/kristapsdz/openrsync

RISC-V SBI bootloader and firmware

https://github.com/riscv-software-src/opensbi

Libraries and utilities to access smart cards

https://github.com/OpenSC/OpenSC/wiki

Full-text search engine for Java

http://opensearch.org

Visualization dashboards for OpenSearch

https://opensearch.org

Visualization dashboards for OpenSearch

https://opensearch.org

Visualization dashboards for OpenSearch

https://opensearch.org

Visualization dashboards for OpenSearch

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

Full-text search engine for Java

https://opensearch.org

Open-source implementation of the Service Location Protocol

http://www.openslp.org/

This package is a collection of SGML/XML tools called OpenSP

http://openjade.sourceforge.net/doc/

Graphical password applet for entering SSH passphrase

http://www.jmknoble.net/software/x11-ssh-askpass/

The portable version of OpenBSD's OpenSSH

https://www.openssh.com/portable.html

TLSv1.3 capable SSL and crypto library

https://www.openssl.org/

TLSv1.3 capable SSL and crypto library

https://www.openssl.org/

TLSv1.3 capable SSL and crypto library

https://www.openssl.org/

API and interchange format for editorial timeline information

https://github.com/PixarAnimationStudios/OpenTimelineIO

UPS daemon for some Belkin UPS's

http://frmb.org/openupsd.html

Development header files for OpenVanilla

https://openvanilla.org/

Tools for storage and manipulation of sparse volumetric data

https://www.openvdb.org/ https://github.com/AcademySoftwareFoundation/openvdb

Secure IP/Ethernet tunnel daemon

https://openvpn.net/community/

Optimizer for PNG files

http://optipng.sourceforge.net/

IETF audio codec

https://opus-codec.org/

Opus playback library

https://www.opus-codec.org/

Geometric sans-serif typeface intended for display purposes

https://github.com/theleagueof/orbitron

Library and toolset to operate arrays of data

https://gstreamer.freedesktop.org/projects/orc.html

Scriptable screen reader

http://live.gnome.org/Orca

Real-time Transport Protocol (RTP) library

https://www.linphone.org/technical-corner/ortp.html

Implementation of the UNIX 6th Edition shell

http://v6shell.org/

COIN-OR Open Solver Interface, an API for calling solver libraries

https://projects.coin-or.org/Osi/

Osinfo database files

https://libosinfo.org/

Tools for managing the osinfo database

https://libosinfo.org/

ISO-C API and CLI for generating Universally Unique Identifiers

http://www.ossp.org/pkg/lib/uuid/

Vulnerability scanner written in Go which uses the OSV database

https://github.com/google/osv-scanner

Show you font info and add new 'name' and 'cmap' tables

https://sourceforge.net/projects/oto/

OpenType Sanitizer

https://github.com/khaledhosny/ots

Browser based on Qt 5

https://otter-browser.org/

Detects publicly disclosed vulnerabilities in project dependencies

https://jeremylong.github.io/DependencyCheck/dependency-check-cli/arguments.html

OwnCloud Desktop Syncing Client

https://github.com/owncloud/client

Plasma5 Oxygen font family

https://cgit.kde.org/oxygen-fonts.git

The Oxygen icon theme for KDE

Library for loading and enumerating of PKCS#11 modules

http://p11-glue.freedesktop.org/p11-kit.html

Perforce client

https://www.perforce.com/