Compiling futuretest v0.1.0 (file:///mnt/d/GIT/futuretest)
error[E0554]: #![feature] may not be used on the stable release channel
 --> src/main.rs:1:1
  |
1 | #![feature(conservative_impl_trait)]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to previous error

error: Could not compile `futuretest`.

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