libalkimia is a library with common classes and functionality used by finance
applications for the KDE SC.

VulkanSceneGraph (VSG), is a modern, cross platform, high performance scene graph library built upon Vulkan graphics/compute API. The software is written in C++17, and follows the CppCoreGuidlines and FOSS Best Practices. The source code is published under the MIT License.

Ngspice is a mixed-level/mixed-signal circuit simulator. Its code is based on three open source software packages: Spice3f5, Cider1b1 and Xspice.

Open Cascade Technology (OCCT), formerly called CAS.CADE, is an open-source software development platform for 3D CAD, CAM, CAE, etc. that is developed and supported by Open Cascade SAS.

The OpenSSL Project is a collaborative effort to develop a robust,
commercial-grade, full-featured, and open source toolkit implementing
the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS
v1) protocols with full-strength cryptography. The project is managed
by a worldwide community of volunteers that use the Internet to
communicate, plan, and develop the OpenSSL toolkit and its related
documentation.

Derivation and License

OpenSSL is based on the excellent SSLeay library developed by Eric A.
Young and Tim J. Hudson. The OpenSSL toolkit is licensed under an
pache-style license, which basically means that you are free to get it
and to use it for commercial and noncommercial purposes.