Volkan, I am happy to report that the change in 2dd7063fb6c6fe73070aded6607a2e2d53613b46 appears to have resolved the issue! After building and installing a local snapshot of log4j-layout-template-json from release-2.x, I now see the following in my test application:
``` {"timestamp.epoch":1635443515353213000,"timestamp.iso8601":"2021-10-28T17:51:55.353Z","severityText":"INFO","body":"Starting count"} {"timestamp.epoch":1635443515360647000,"timestamp.iso8601":"2021-10-28T17:51:55.360Z","severityText":"INFO","body":"Event 0"} {"timestamp.epoch":1635443516365136000,"timestamp.iso8601":"2021-10-28T17:51:56.365Z","severityText":"INFO","body":"Event 1"} {"timestamp.epoch":1635443517365604000,"timestamp.iso8601":"2021-10-28T17:51:57.365Z","severityText":"INFO","body":"Event 2"} ``` After several more runs, including runs over SLF4J, the epoch timestamp resolver operates as expected. I am also happy to report that a pattern layout also continues to operate as expected. Speaking to the test added in 2dd7063f, I ran exactly that test against the previous head b6774209, and indeed the test fails. Also a good sign, the test seems to cover the logging behavior! Seen as follows: ``` [ERROR] Failures: [ERROR] TimestampResolverTest.epoch_nanos_should_not_overlap:43->lambda$epoch_nanos_should_not_overlap$1:69 Found duplicate(s): [1635444597296722000L] in: [1635444597296722000L, 1635444597296722000L, 1635444597296722000L, 1635444597296722000L, 1635444597296722000L] ``` Meanwhile, of course, the test passes in 2dd7063f. Thank you for your help here. I am sorry that I wasn't able to isolate the issue more quickly, let alone provide a test case myself. Looking forward to this change arriving in a future release. Hope you are feeling better, too! Andrew