diff --git a/doc/build-unix.txt b/doc/build-unix.txt
index 53893398..e1a1805a 100644
--- a/doc/build-unix.txt
+++ b/doc/build-unix.txt
@@ -65,6 +65,7 @@ sudo apt-get install libdb4.8-dev
 sudo apt-get install libdb4.8++-dev
  Boost 1.40+: sudo apt-get install libboost-all-dev
  or Boost 1.37: sudo apt-get install libboost1.37-dev
+sudo apt-get install libqrencode-dev
 
 If using Boost 1.37, append -mt to the boost libraries in the makefile.