See individual source files for copyright and licensing details, and in particular THIRD-PARTY.md for details of third-party libraries used or included in this project. The overall license of pressure-vessel is LGPL-2.1-or-later <https://spdx.org/licenses/LGPL-2.1-or-later.html>. Unit tests, scripts, the build system, etc. are mostly under the permissive MIT/X11 license <https://spdx.org/licenses/MIT.html>.