Here are a couple of possibilities:

As requested, I added site on the grey outline: please look which font / color do you like better.

http://imgur.com/a/3gFIm

adding one more to track all options

Maria, i got some feedback from the team.

If you could try couple of more ideas.
1. shrink the font size so it will not be that noticeable, but still readable
2. place the pulpproject.org more to the left corner like here http://hexb.in/vector/roxygen2.svg
3. Make sure that letters like p, j, g are not crossing the border(to the grey area) so maybe you would need to lift the writing a bit
4. Try the mentioned above things with grey and blue colours.

Thank you a lot for your time and patience!

HI! I'd ask you to please select 1 position and we can try to further iterate on size and colors if needed. To check sizes IRL, print the image on a4 sized paper. Thank you!

Hey! I put togeher the versions you wanted to see and made fonts a bit thicker; and looks like we chose Cabin over Overpass. Let me know if you'd like to print these out - I'll put them on an a4 sized background.

Maria, we decided to go with this option, gray colour in the middle. https://postimg.org/image/m4wee030r/
Just please make sure the font size, once the sticker will be printed, will be readable.
I cannot say i can am able to read the current size font but it maybe because the example of the logo is too small.

Also, would be good if the writing itself would be a bit darker then the border so it would not merge ( maybe it is darker, i just don't see it)

A4 if you want to try printing it out:

20% gray

Masha, i would like to ask you to prepare the logo formats for printing,
We decided to go with 30% of grey.
Also please include svg and png format since we want to put the logo here http://hexb.in/ and they do require those 2 formats.

thanks a lot and let me know in case you have some questions.

@ipanova I sent you an archive with many possible formats to your email; attaching some files here, just in case: