Merge pull request #38351 from grahamc/user-channels

Add user channels to the default nix path

nixos/doc/manual/release-notes/rl-1809.xml

@@ -20,10 +20,21 @@ has the following highlights: </para>
 <itemizedlist>
   <listitem>
     <para>
-      TODO
+      User channels are now in the default <literal>NIX_PATH</literal>,
+      allowing users to use their personal <command>nix-channel</command>
+      defined channels in <command>nix-build</command> and
+      <command>nix-shell</command> commands, as well as in imports like
+      <code>import &lt;mychannel&gt;</code>.
     </para>
+    <para>For example</para>
+    <programlisting>
+$ nix-channel --add https://nixos.org/channels/nixpkgs-unstable nixpkgsunstable
+$ nix-channel --update
+$ nix-build '&lt;nixpkgsunstable&gt;' -A gitFull
+$ nix run -f '&lt;nixpkgsunstable&gt;' gitFull
+$ nix-instantiate -E '(import &lt;nixpkgsunstable&gt; {}).gitFull'
+</programlisting>
   </listitem>
-
 </itemizedlist>
 
 </section>

nixos/modules/services/misc/nix-daemon.nix

@@ -338,7 +338,9 @@ in
       nixPath = mkOption {
         type = types.listOf types.str;
         default =
-          [ "nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs"
+          [
+            "$HOME/.nix-defexpr/channels"
+            "nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs"
             "nixos-config=/etc/nixos/configuration.nix"
             "/nix/var/nix/profiles/per-user/root/channels"
           ];