Hi, I'm trying to remove redundant logback config files by using janino's conditional processing. Below is the conditional logic which I had added within the configuration tag (along with the appender details) <root level="INFO"> <appender-ref ref="ROLLING" /> <!-- use console appender on windows, email appender on linux --> <if condition='property("os.name").contains("win")'> <then> <appender-ref ref="CONSOLE" /> </then> <else> <appender-ref ref="EMAIL" /> </else> </if> </root> but this throws the below errors when logback is initialized 12:30:34,877 |-ERROR in ch.qos.logback.core.joran.spi.Interpreter@90:55 - no applicable action for [if], current pattern is [[configuration][root][if]] 12:30:34,877 |-ERROR in ch.qos.logback.core.joran.spi.Interpreter@91:10 - no applicable action for [then], current pattern is [[configuration][root][if][then]] 12:30:34,877 |-ERROR in ch.qos.logback.core.joran.spi.Interpreter@92:35 - no applicable action for [appender-ref], current pattern is [[configuration][root][if][then][appender-ref]] 12:30:34,877 |-ERROR in ch.qos.logback.core.joran.spi.Interpreter@94:10 - no applicable action for [else], current pattern is [[configuration][root][if][else]] 12:30:34,877 |-ERROR in ch.qos.logback.core.joran.spi.Interpreter@95:35 - no applicable action for [appender-ref], current pattern is [[configuration][root][if][else][appender-ref]] The configuration works fine if I remove the conditional logic and use something like <root level="INFO"> <appender-ref ref="ROLLING" /> <appender-ref ref="CONSOLE" /> <appender-ref ref="EMAIL" /> </root> I have already added janino as a Maven dependency. How can I configure this correctly in such a way that the CONSOLE appender is used only on Windows and the EMAIL appender everywhere else? Thanks, Aneesh