1. Use pip-tools to generate a pinned requirements list. This is used to build artifacts like docker images, installer bundles etc. All pins are upgraded periodically (manually). Any version changes are inspected (this requires "knowing" your dependencies a bit and which ones might cause problems). Finally the resulting artifacts are manually tested.

2. An automated build of master every 24 hours from completely unpinned versions. That is installing the package fresh from pyproject.toml. The automated test suite will reveal any upcoming breakage that would happen if we continue without upper bounds on certain packages. If there is breakage we decide whether to accommodate the new breaking dependencies or constrain them with an upper bound (perhaps recording a tech debt).