* [`nix-channel`](../command-ref/nix-channel.md) now supports a `--list-generations` subcommand.
* The function [`builtins.fetchClosure`](../language/builtins.md#builtins-fetchClosure) can now fetch input-addressed paths in [pure evaluation mode](../command-ref/conf-file.md#conf-pure-eval), as those are not impure.
* Nix now allows unprivileged/[`allowed-users`](../command-ref/conf-file.md#conf-allowed-users) to sign paths.
Previously, only [`trusted-users`](../command-ref/conf-file.md#conf-trusted-users) users could sign paths.
* Nested dynamic attributes are now merged correctly by the parser. For example:
It allows writing expressions that are very hard to read, for instance when there are many lines of code between two declarations of the same attribute.
This has been around for a long time and is therefore supported for backwards compatibility, but should not be relied upon.
* Tarball flakes can now redirect to an "immutable" URL that will be recorded in lock files. This allows the use of "mutable" tarball URLs like `https://example.org/hello/latest.tar.gz` in flakes. See the [tarball fetcher](../protocols/tarball-fetcher.md) for details.