One thing I was really seduced by getting a member of the TNG dev team was the totally cool and enterprise level way the product is created.
Unit tests are crucial. And not just by the corporate quality rulebook: developers have adopted the concept of only treating a code ready when sufficient tests are also created. So we have tests, lots of tests covering as much of the source and the functionality as possible. Today Gyeby - the TNG dev lead - revealed that for the PortalFileSystem we have the 74% of source covered by tests, and for the PortalEngine this is 45%. And of course - we will release the test projects together with the Portal Engine TNG source - so everyone can rely on it. This is pretty cool I guess.
Our source management is based on Team Foundation Server and check in time automated test runs provide us continuous integration features. No source can get in the system unless it is proved itself correct and GREEN. This saves us from regular homicide situations when let's say his or her loosely tested and failing interface implementation would ruin my silverlight prototype application or vice versa.
Plus source code related events from our TFS are routed to the company quality management framework - required by the ISO9000. This puts the question of the source code quality management to overall company focus.
We are building an enterprise portal engine not only in the means of product functionality.