LFortran is a modern open-source (BSD licensed) interactive Fortran compiler built on top of LLVM. It can execute user’s code interactively to allow exploratory work (much like Python, MATLAB or Julia) as well as compile to binaries with the goal to run user’s code on modern architectures such as multi-core CPUs and GPUs.

Package, dependency and environment management for any language—Python, R, Ruby, Lua, Scala, Java, JavaScript, C/ C++, FORTRAN, and more.

Conda is an open source package management system and environment management system that runs on Windows, macOS and Linux. Conda quickly installs, runs and updates packages and their dependencies. Conda easily creates, saves, loads and switches between environments on your local computer. It was created for Python programs, but it can package and distribute software for any language.

Yet another password manager.

GMAT is designed to model, optimize, and estimate spacecraft trajectories in flight regimes ranging from low Earth orbit to lunar applications, interplanetary trajectories, and other deep space missions. Analysts model space missions in GMAT by first creating resources such as spacecraft, propagators, estimators, and optimizers.

SILE is a typesetting system. Its job is to produce beautiful printed documents.
SILE follows TeX in each of these three areas; it contains a slavish port of the TeX line-breaking algorithm which has been tested to produce exactly the same output as TeX given equivalent input. But as SILE is itself written in an interpreted language, it is very easy to extend or alter the behaviour of the SILE typesetter.

Xpra is an open-source multi-platform persistent remote display server and client for forwarding applications and desktop screens.
It gives you remote access to individual applications or full desktops.
On X11, it is also known as screen for X11: it allows you to run programs, usually on a remote host, direct their display to your local machine, and then to disconnect from these programs and reconnect from the same or another machine, without losing any state.
It can also be used to forward full desktops, from X11 servers, MS Windows, or Mac OS X.

Xpra also allows forwarding of sound, clipboard and printing services.
Sessions can be accessed over SSH, or password protected over plain TCP sockets with or without SSL.
Xpra is usable over reasonably slow links and does its best to adapt to changing network bandwidth constraints.

Galileo/GPS/BeiDou/Glonass open source monitor.
Found via https://hackaday.com/2019/09/24/tracking-the-satellites-that-keep-us-on-track-monitoring-gps-galileo-beidou-and-glonass/

Just what it says. Can use Dropbox, Google Drive or WebDAV as back-end storage.

A fully-free (as in libre) alternative to Github, found via
https://github.com/CodyReichert/awesome-cl

Sequoia is a cool new OpenPGP implementation.  It consists of several
crates, providing both a low-level and a high-level API for dealing
with OpenPGP data.
It is written in Rust