WildFly 14 has been released and is now Java EE 8 certified. From now on, WildyFly only provides EE8 APIs by default in all its run modes. The Java EE 8 preview option and Java EE 7 mode have been dropped.
Since Java EE 8 is backwards compatible, Java EE 7 and older applications will still run in the new WildFly version.
Besides the promotion of Java EE 8 as new default mode, WildFly 14 comes with some new standards for Eclipse MicroProfile. The new APIs MP Config, MP OpenTracing and MP Health are now part of WildFly 14 and will help with the use of container environments.
Another new improvement is a high performance connection pool, provided by the Agroal project, although JCA is still activated by default.
The complete list of all new additions can be found in the release notes.