I have been a REAPER user for years and lately I’ve been using the unofficial Linux release.
Getting Started
Here are a few links to get started:
Running LV2 and LADSPA Plugins
The best way I have found to integrate these Linux-native formats into my workflow has been to use Carla. It’s a program that hosts other plugins and can be imported as a VST or VSTi (important because REAPER does not directly support LV2 and LADSPA plugins).