For some reason you develop a new version of com.stackoverflow (say version 1.1), then you should:
com/stackoverflow/1.1
on ${WILDFLY_HOME}/modules
<?xml version="1.0" encoding="UTF-8"?>
<module xmlns="urn:jboss:module:1.1" name="com.stackoverflow" slot="1.1">
<resources>
<resource-root path="stackoverflow.jar"/>
</resources>
</module>
Note the slot="1.1"
modification on this example