Ragdoll Studio 3 by Candlelight Interactive does it right. The reason for this is that it installs into Plugins/ with editor extensions in Plugins/Editor/ Honorable mention for Vectrosity which comes in dll and source form. So I can just choose to install the dll if I don't want to change source. I prefer assets which build fine and don't ruin compile times during development. I wonder why nobody else bothers? I guess it's because they aren't actually making large games with lots of assets. So if you want to be nice to your customers, you'll want to install into Plugins/YourAsset/ and put your editor scripts inside Plugins/Editor/ or Supply a precompiled dll. Pretty sick of 15 second compile times. Manually fixing this brings it down to 2 seconds. However, have to repeat the process endlessly each asset update. Aware of an asset that does this for me, but it doesn't exactly play nice with version control. Should not have to purchase yet another asset to handle this for me or do it manually tbh. Also, Unity should have shown leadership here and utterly failed to do so. But looking forward I think we need some guidelines about this. It gets to a point where people are just put off buying assets due to how much they extend not reduce development times. In any case something can be done about it, for new assets. Think of your customers, you are on one hand increasing their productivity, but on the other hand, reducing it.