Programs for locking and unlocking files and mailboxes

https://tracker.debian.org/pkg/lockfile-progs

Fast and flexible logging library for Java

https://logging.apache.org/log4j/1.2/

Auditing tool for system logs on Unix boxes

https://salsa.debian.org/debian/logcheck

Server-side data ingestion and transformation tool

https://www.elastic.co/products/logstash

Lohit fonts

https://fedorahosted.org/lohit/

The JGoodies Looks improve the appearance of your Java applications

http://www.jgoodies.com

Lightweight Jabber client library

https://mcabber.com/

Receive/Send files via X/Y/ZMODEM protocol. (unrestrictive)

http://www.ohse.de/uwe/software/lrzsz.html

Display information about the CPU architecture

https://github.com/NanXiao/lscpu

Lists information about open files (similar to fstat(1))

https://github.com/lsof-org/lsof

Libraries to instrument and trace user applications

https://github.com/lttng/lttng-ust

Lua bindings to libraries using GObject-Introspection

https://github.com/pavouk/lgi

Small, compilable scripting language providing easy access to C code

https://www.lua.org/

Small, compilable scripting language providing easy access to C code

https://www.lua.org/

Powerful, efficient, lightweight, embeddable scripting language

https://www.lua.org/

Just-In-Time Compiler for Lua

https://luajit.org/luajit.html

Just-In-Time Compiler for Lua (OpenResty branch)

https://github.com/openresty/luajit2

Full-text search engine for Java

http://lucene.apache.org/java/

Locale and ISO 2022 support for Unicode terminals

https://invisible-island.net/luit/

Archive manager from the Lumina Desktop

https://lumina-desktop.org/

Scientific calculator from the Lumina Desktop

https://lumina-desktop.org/

Lumina Desktop Environment

https://lumina-desktop.org/

File properties utility from the Lumina Desktop

https://lumina-desktop.org/

Insight file manager from the Lumina Desktop

https://lumina-desktop.org/

Alarm/notification utility from the Lumina Desktop

https://lumina-desktop.org/

Screenshot utility from the Lumina Desktop

https://lumina-desktop.org/

Plaintext editor from the Lumina Desktop

https://lumina-desktop.org/

XDG desktop entry creator from the Lumina Desktop

https://lumina-desktop.org/

Display the moon's phase

http://www.vector.co.jp/soft/dos/edu/se004823.html

GNUstep news reader

Lightweight C++ API for Lua

https://github.com/jmmv/lutok/

Open standard for audio plugins (successor to LADSPA)

https://lv2plug.in/

Non-graphical, text-based World-Wide Web client

https://lynx.invisible-island.net/

Lossless data compressor based on the LZMA algorithm

http://www.nongnu.org/lzip/

High-ratio LZMA compressor

https://www.7-zip.org/sdk.html

Portable speedy, lossless data compression library

http://www.oberhumer.com/opensource/lzo/

Fast file compressor similar to gzip, using the LZO library

http://www.oberhumer.com/opensource/lzop/

Data files for the m17n library

http://www.nongnu.org/m17n/

The m17n library documentation

http://www.nongnu.org/m17n/

Library for multilingual text handling

http://www.nongnu.org/m17n/

GNU M4

https://www.gnu.org/software/m4/m4.html

Bonjour (zero-configuration networking) by Apple

https://developer.apple.com/bonjour/

Apple mDNS responder - BSD nsswitch module

https://developer.apple.com/bonjour/

Magus runtime utilities for build cluster

Mailing list manager with user-friendly web front-end

https://www.list.org/

Utilities, daemons, and filters for processing e-mail

https://mailutils.org/

Dependency generator for makefiles

https://www.x.org/archive/X11R7.5/doc/man/man1/makedepend.1.html

Perl scripts to assist in the generation and application of patches

https://www.vromans.org/johan/software/sw_makepatch.html

Convert nroff(1) man pages to HTML

https://dickey.his.com/scripts/man2html.html

Convert man pages to HTML

http://man2web.sourceforge.net/