> The TH3 test harness is a set of proprietary tests [...]

> The dbsqlfuzz engine is a proprietary fuzz tester.

It's interesting that an open-source (actually public domain) software uses some proprietary tests. It never occurred to me that this was a possibility, though in retrospective it's obviously possible as long as the tests are not part of the release.

Could this be an alternative business model for "almost-open-source" projects? Similar to open-core, but in this case the project would easy to copy (open features), hard to modify (closed tests).