Datatorrent the largest contributor to the Apex project has closed shop[1], the project hasn't retired but development has significantly slowed down. The Gearpump project has voted to retire[2].
Do people know if these runners are being used? Do people spend enough time on supporting/updating code in these areas or looking at test flakes that warrant supporting them still? Are there other runners in a similar situation as to Apex or Gearpump? Should we revisit this question once we have a larger integration that we want to do like SplittableDoFn or portability? 1: https://www.datanami.com/2018/05/08/datatorrent-stream-processing-startup-folds/ 2: https://lists.apache.org/thread.html/03fc0421bb425f79d623863335bc2b81e4b6c77a169f508aadce7785@%3Cdev.gearpump.apache.org%3E