Need help with running tests

[ww6726]

I received this error msg while trying to cargo test marlin

error[E0554]: #![feature] may not be used on the stable release channel
--> /mnt/c/phd_3rd_year/multiprover-snark/mpc-trait/src/lib.rs:1:1
|
1 | #![feature(associated_type_defaults)]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

For more information about this error, try rustc --explain E0554.
error: could not compile mpc-trait due to previous error

Any suggestions?

[ww6726]

Does the repo have to use stable, or can i get away with nightly?