How to organize a project with local scripts in subdirectories using dub?

[Pavel Shkadzko]

I have the following project structure.

my_proj/
     script_1/runme_1.d
     script_2/runme_2.d
     evaluator.d

The project has a library dependency:

"dependencies": {
     "mir": "~>3.2.0",
},

The "evaluator.d" script contains some general functions that 
convert dataset and pass it to "runme_1.d" and "runme_2.d" 
scripts the following way:

import mir.ndslice;

void main() {
     import script_1.runme_1 : runTask1;
     import script_2.runme_2 : runTask2;

     mir_slice!(real*, 1LU, cast(mir_slice_kind)2)[]) dataset = 
convertDataset("data.txt");
     runTask1(dataset);
     //runTask2(dataset); //disable for now
}

So, basically what I need is to be able to run "./evaluator" and 
get the results by running the corresponding scripts.

I am trying to build the project the following way:

dub build --compiler=ldc2 --single evaluator.d

I get the following error:

Performing "debug" build using ldc2 for x86_64.
mir-core 1.0.2: target for configuration "library" is up to date.
mir-algorithm 3.7.2: target for configuration "default" is up to 
date.
mir-linux-kernel 1.0.1: target for configuration "library" is up 
to date.
mir-random 2.2.8: target for configuration "extended" is up to 
date.
survey ~master: building configuration "application"...
lld-link: error: undefined symbol: 
_D5runme_114runTask1FS3mir7ndslice5slice__T9mir_sliceTPeVmi2VEQBoQBnQBi14mir_slice_kindi2ZQBvZv
>>> referenced by C:\Users\user\my_proj\evaluator.d:89
>>>               .dub\obj\evaluator.obj:(_Dmain)
Error: linking with LLD failed
ldc2 failed with exit code 1.

How should I organize my project for this kind of setup?

(I am sorry for the absence of code formatting. I could not find 
any quick howto here)