Intro: Mention binary caches

1 files changed, 10 insertions, 3 deletions

diff --git a/doc/manual/introduction/about-nix.xml b/doc/manual/introduction/about-nix.xml
index 54c18a1e6127..56ec39916b6c 100644
--- a/doc/manual/introduction/about-nix.xml
+++ b/doc/manual/introduction/about-nix.xml
@@ -161,13 +161,19 @@ library and the compiler) would have to built, at least if they are
 not already in the Nix store.  This is a <emphasis>source deployment
 model</emphasis>.  For most users, building from source is not very
 pleasant as it takes far too long.  However, Nix can automatically
-skip building from source and download a pre-built binary instead if
-it knows about it.  <emphasis>Nix channels</emphasis> provide Nix
-expressions along with pre-built binaries.</para>
+skip building from source and instead use a <emphasis>binary
+cache</emphasis>, a web server that provides pre-built binaries. For
+instance, when asked to build
+<literal>/nix/store/b6gvzjyb2pg0…-firefox-33.1</literal> from source,
+Nix would first check if the file
+<uri>http://cache.nixos.org/b6gvzjyb2pg0….narinfo</uri> exists, and if
+so, fetch the pre-built binary referenced from there; otherwise, it
+would fall back to building from source.</para>
 
 </simplesect>
 
 
+<!--
 <simplesect><title>Binary patching</title>
 
 <para>In addition to downloading binaries automatically if they’re
@@ -176,6 +182,7 @@ package in the Nix store into a new version.  This speeds up
 upgrades.</para>
 
 </simplesect>
+-->
 
 
 <simplesect><title>Nix Packages collection</title>