Open Source Software for macOS
LispPad
LispPad is a simple, lightweight, IDE for developing and running Scheme code on macOS. The language supported by the integrated development environment LispPad is based on the R7RS (small) standard of the Scheme programming language. LispPad provides the a wide range of components inclduing a fully integrated Scheme interpreter, a large set of libraries, a text editor supporting syntax highlighting, smart indentation, parenthesis matching and text completion.
FlexGet
FlexGet is a free and open-source multipurpose automation tool for all of your media with support for torrents, nzbs, podcasts, comics, TV, movies, RSS, HTML, CSV, and more.
Shotcut
A free and openly developed video editing software that works cross-platform. Shotcut is developed on the MLT Multimedia Framework and is avalible for FreeBSD, Linux, macOS and Windows. Shotcut is released as open-source software under the GPLv3.
Termius
Termius is the SSH client that works on both Desktop and Mobile. The application lets you organize hosts into groups while allowing share settings across users. Terminus uses end-to-end encryption to ensure your data remains safe and secure, while keeping connection and command history.
Irssi
Irssi is a terminal based IRC client for UNIX-based operating systems. Irssi comes with IRC built-in and is multi-protocol friendly for module authors, it also support integration with SILC and ICB protocols via plugins. The application easily integrates with your window manager, your terminal emulator, your remote connection, your terminal multiplexer, your IRC bouncer and your IRC adapter. Allowing you to use Irssi virtually everywher throughout your system. Irssi is free software licensed under the GPLv2, available for macOS, Linux, BSD, Solaris, and Cygwin.
muCommander
muCommander is a lightweight, cross-platform file manager with a dual-pane interface. The application runs on any operating system with Java support including macOS, Windows, Linux, BSD and Solaris. Featuring a virtual filesystem with support for local volumes, FTP, SFTP, SMB, NFS, HTTP, Amazon S3, Hadoop HDFS and Bonjour. With muCommander you can quickly copy, move, rename files, create directories, email files and zip files can be modified live without the requirement of re-compressing entire archives. muCommander is released as free and open source software under the GNU General License.
RedisGraph
RedisGraph is the first free and open source queryable Property Graph database to use sparse matrices to represent the adjacency matrix in graphs and linear algebra to query the graph.
USBImager
A really simple open-source, GUI application that writes compressed disk images to USB drives and creates backups. USBImager is avalible for Linux, macOS, and Windows.