Rust = bust?

[swedebugia]

Hi

I'm eager to begin building grin which relies on rust 1.34+ but I get 
this from a guix checkout compiled yesterday:

The following derivations would be built:
   /gnu/store/9d9r8c70yz329gl01ywgvf4gql9ir31f-grin-1.1.0.drv
   /gnu/store/hgpjq9f5z6rpmidsij7nrp20ad38vg98-rust-1.35.0.drv
   /gnu/store/1lmw4151bbz6b0scd2gvxsgh0ad25vwb-rust-1.34.1.drv
   /gnu/store/cssgpdzm63zd8vdxr9pkhmplr5c0wglr-rust-1.33.0.drv
   /gnu/store/ivkmn1gisdz3xys6gdmncr1vfpwp1a0v-rust-1.32.0.drv
   /gnu/store/11b81ijyi1wnp41wgyqjwgxvg28hk4hg-rust-1.31.1.drv
   /gnu/store/1yis5vsvqpf0gaynnfqpnin45yp3cw4l-rust-1.30.1.drv

This has not changed for days/a week.

When investigation on the CI I find that rust above 1.30 have not build 
on master for x86-64 since april.

http://ci.guix.gnu.org/search?query=rust-1.30
->
http://ci.guix.gnu.org/build/1303680/details "dependency failed"

What does that mean?

What is going on?

Also could somebody tell me how to shut off the tests if I choose to 
build them myself?
--
Cheers Swedebugia