I have a maven project that leverages arquillian tests for multiple unit cases. One for validators and another for DeltaSpike Data module.

The DeltaSpike Data module runs first, followed by the validator one (just happens to be that order, no specific required order). The validator one includes a class deactivator extension that disables an extension on boot. The data module one didn't have this. We began seeing that the data test would pass but the validator suddenly fail. Adding our deactivator to the data module test caused the validator test to suddenly work (this was great).

It appears that the CDI extensions provided by the archive are only processed once, I would expect that they get processed per deployment as each deployment archive is run independently at the unit level.