Build-tool for Erlang that follows OTP principles

https://github.com/rebar/rebar

Build tool for Erlang

https://www.rebar3.org/

Converts files between character sets and usages

http://www.gnu.org/software/recode/recode.html

Persistent key-value database with built-in net interface

https://redis.io/

Persistent key-value database with built-in net interface

https://redis.io/

Persistent key-value database with built-in net interface

https://redis.io/

High-level interface for RDF

http://librdf.org

Microsoft .Net Portable Class Library Reference Assemblies

https://blogs.msdn.microsoft.com/dotnet/2013/10/14/portable-class-library-pcl-now-available-on-all-platforms/

GTK+ Remote Desktop Client (lite flavor)

https://www.remmina.org/

Graphical interface to rdesktop

http://gap.nongnu.org/remotedesk/index.html

Fast, secure, efficient backup program

https://restic.github.io

Uncompile an rgb color-name database

https://gitlab.freedesktop.org/xorg/app/rgb

Utility and library for computing and checking of file hashes

http://rhash.sourceforge.net/

Audio player for GNOME

https://wiki.gnome.org/Apps/Rhythmbox

Command line search tool

http://blog.burntsushi.net/ripgrep/

GNU Compiler Collection for bare metal riscv64 cross-development

https://gcc.gnu.org/

Image viewer with Xfce integration

https://goodies.xfce.org/projects/applications/ristretto

Flexible message logging facility for C++

https://www.arg0.net/rlog

Recurrent neural network for audio noise reduction

https://github.com/xiph/rnnoise

Roboto typeface family

http://developer.android.com/design/style/typography.html

Fully skinnable XHTML/CSS webmail written in PHP

https://roundcube.net/

Classic skin/theme for Rouncube webmail

https://github.com/roundcube/classic/

Larry skin/theme for Rouncube webmail

https://github.com/roundcube/larry/

Thunderbird Labels plugin for RoundCube webmail

https://github.com/mike-kfed/roundcube-thunderbird_labels

Firmware for RaspberryPi Single Board Computer

https://github.com/raspberrypi/firmware

Convert .rpm files to cpio format

The RPM Package Manager

https://rpm.org/

Round Robin Database Tools

http://www.rrdtool.org/

Fast spam filtering system

https://rspamd.com/

Restricted Secure SHell only for sftp or/and scp

http://www.pizzashack.org/rssh/index.shtml

Network file distribution/synchronization utility

http://rsync.samba.org/

Syslogd supporting SQL, TCP, and TLS

https://www.rsyslog.com/

Generic RF data receiver and decoder for ISM band devices

https://github.com/merbanan/rtl_433

Command-line tool that performs SDR with RTL2832-based USB sticks

https://sdr.osmocom.org/trac/wiki/rtl-sdr

Realtek USB bluetooth adaptor firmwares used by rtlbtfw(8)

https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git

RTMP streams download utility

http://rtmpdump.mplayerhq.hu/

BitTorrent Client written in C++

https://github.com/rakshasa/rtorrent

Ruby interface to Oracle Berkeley DB revision 2 or later

https://github.com/knu/ruby-bdb

Integrated environment for Bioinformatics written in Ruby

http://bioruby.org/

Binary data dumper module for Ruby

http://www.geocities.co.jp/SiliconValley-Oakland/2986/

Package management framework for the Ruby language

https://rubygems.org/

Object-oriented interpreted scripting language

https://www.ruby-lang.org/en/

Object-oriented interpreted scripting language

https://www.ruby-lang.org/en/

Object-oriented interpreted scripting language

https://www.ruby-lang.org/en/

Fast, open source text processor and publishing toolchain

https://asciidoctor.org/

Ruby extension for base32 encoding and decoding

https://github.com/stesla/base32

Encode and decode binary data using a Base64 representation

https://github.com/ruby/base64

Integrated environment for Bioinformatics written in Ruby

http://bioruby.org/

Collection of miscellaneous utilities for bioinformatics

https://github.com/bioruby/bioruby-executables

Emulate Bio::Fetch object

https://github.com/ngoto/bioruby-old-biofetch-emulator