Update release notes

This commit is contained in:
Eelco Dolstra 2022-03-31 17:33:06 +02:00
parent 7537097284
commit d63a5f5dd3

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@ -14,3 +14,21 @@
This function is only available if you enable the experimental This function is only available if you enable the experimental
feature `fetch-closure`. feature `fetch-closure`.
* New experimental feature: *impure derivations*. These are
derivations that can produce a different result every time they're
built. Here is an example:
```nix
stdenv.mkDerivation {
name = "impure";
__impure = true; # marks this derivation as impure
buildCommand = "date > $out";
}
```
Running `nix build` twice on this expression will build the
derivation twice, producing two different content-addressed store
paths. Like fixed-output derivations, impure derivations have access
to the network. Only fixed-output derivations and impure derivations
can depend on an impure derivation.