Runtime monitoring and logging are fundamental techniques for analyzing and supervising the behavior of computer programs. However, supporting these techniques for a given language induces significant development costs that can hold language engineers back from providing adequate logging and monitoring tooling for new domain-specific modeling languages. Moreover, runtime monitoring and logging are generally considered as two different techniques: they are thus implemented separately which makes users prone to overlooking their potentially beneficial mutual interactions. We propose a language-agnostic, unifying framework for runtime monitoring and logging and demonstrate how it can be used to define loggers, runtime monitors and combinations of the two, aka. moniloggers. We provide an implementation of the framework that can be used with Java-based executable languages, and evaluate it on 2 implementations of the NabLab interpreter, leveraging in turn the instrumentation facilities offered by Truffle, and those offered by AspectJ.