I have a test that is trying to use SLF4J 1.8.0-alpha1 and am getting the error below - which implies that SLF4J doesn’t work with Logback. Why isn’t the SLF4J binding backward compatible? 

SLF4J: No SLF4J providers were found.
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#noProviders for further details.
SLF4J: Class path contains SLF4J bindings targeting slf4j-api versions prior to 1.8.
SLF4J: Ignoring binding found at [jar:file:/Users/rgoers/.m2/repository/ch/qos/logback/logback-classic/1.2.2/logback-classic-1.2.2.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#ignoredBindings for an explanation.

Ralph