A little DUB question

[thedeemon]

I've missed all the DUB discussions here and couldn't find the 
answer to my question in the docs, so here it is, very simple:
I've got an app with one dependency stated in package.json as
        "dependencies": {
                "pegged": "~master"
        }
When I build my app with
dub build --build=release
the app itself gets compiled in release mode, but the library it 
depends on (in this case Pegged) gets compiled in Debug, so the 
binary ends up 2-3 times larger than if I build everything myself 
without DUB.
What is the right way to build everything in release using DUB 
here?