`symlinkjoin` doesn't create link to package in `bin/`

I’ve created av overlay[1], but I’m having a problem when I try to create a wrapper.

The problem is that when I try to create derivation durden containing arcan-unwrapped and durden-unwrapped using symlinkjoin, the resulting derivation durden (wrapped) doesn’t have a link to durden-unwrapped under <derivation-path>/bin/. Both arcan-unwrapped and durden-unwrapped and elements of the paths list.

I need both Durden and Arcan if I want to install Durden, because the former is ran with the later. I.e., to start Durden you need to run arcan ./durden.

I’ve tried to find the cause of the problem, but haven’t been able to find one. I’ve tested to hard code the paths lists[2] to [ durden-unwrapped ] ++ [ arcan ] (I added durden-unwrapped to the function’s argument set.

[1] https://github.com/a12l/arcan-overlay
[2] https://github.com/a12l/arcan-overlay/blob/4f0b669b46209e2ba746ae3bb9015df75f8fbae1/wrapper.nix#L11