Building platform specific code for multiple platforms with gradle

We are trying to build a plugin with optional extensions for some of IDE's (like PyCharm). We have found mention about optional dependency on modules in plugin's manifest file here https://www.jetbrains.org/intellij/sdk/docs/basics/getting_started/plugin_compatibility.html, but we've failed to find a good way to add pycharm's code in compile time with gradle. There is workaround with intellij.alternativeIdePath property - but first of all it looks a bit dirty (it's necessary to download ide manually) and secondly - this approach doesn't look scalable for multiple IDEs case, e.g. if i want to put specific code for idea, pycharm and webstorm into single plugin.
Is there a valid way to make plugins like this?