Hi @DavidKing2020 . A SpikeMonitor is not a function, so it cannot be added as a dependency. This mechanism is not meant as a general interface to arbitrary Brian objects. Since standalone mode uses global variables for all group variables (including variables of a SpikeMonitor), you can access them from functions using their name if necessary. See this discussino for more information on how to do that: User-defined functions - #4 by mdepitta
That said, maybe you could explain what you want to achieve? I’d try to implement as much as possible with Brian’s standard mechanisms, and only use hand-written C++ code if absolutely necessary.