diff --git a/nixos/doc/manual/release-notes/rl-unstable.xml b/nixos/doc/manual/release-notes/rl-unstable.xml
index 837fdf07cec..a7ba1cb1ff5 100644
--- a/nixos/doc/manual/release-notes/rl-unstable.xml
+++ b/nixos/doc/manual/release-notes/rl-unstable.xml
@@ -83,6 +83,64 @@ was accordingly renamed to bomi
+
+
+ Haskell packages can no longer be found by name, i.e. the commands
+ nix-env -qa cabal-install and nix-env -i
+ ghc will fail, even though we do ship
+ both cabal-install and ghc.
+ The reason for this inconvenience is the sheer size of the Haskell
+ package set: name-based lookups such as these would become much
+ slower than they are today if we'd add the entire Hackage database
+ into the top level attribute set. Instead, the list of Haskell
+ packages can be displayed by
+
+
+nix-env -f "<nixpkgs>" -qaP -A haskellPackages
+
+
+ and packages can be installed with:
+
+
+nix-env -f "<nixpkgs>" -iA haskellPackages.cabal-install
+
+
+
+
+
+ Previous versions of NixOS come with a feature called
+ ghc-wrapper, a small wrapper script that allows
+ GHC to transparently pick up on libraries installed in the user's
+ profile. This feature has been deprecated;
+ ghc-wrapper was removed from the distribution.
+ The proper way to register Haskell libraries with the compiler now
+ is the haskellPackages.ghcWithPackages
+ function.
+ https://nixos.org/wiki/Haskell
+ provides much information about this subject.
+
+
+
+
+
+ All Haskell builds that have been generated with version 1.x of
+ the cabal2nix utility are now invalid and need
+ to be re-generated with a current version of
+ cabal2nix to function. The most recent version
+ of this tool can be installed by running
+ nix-env -i cabal2nix.
+
+
+
+
+
+ The haskellPackages set in Nixpkgs used to have a
+ function attribute called extension that users
+ could override in their ~/.nixpkgs/config.nix
+ files to configure additional attributes, etc. That function still
+ exists, but it's now called overrides.
+
+