diff --git a/.zshrc b/.zshrc
index 569099b..a0ec309 100644
--- a/.zshrc
+++ b/.zshrc
@@ -20,6 +20,15 @@
 
  eval "$(sheldon source)"
 
+ # disable unneeded fast-syntax-highlighting modules.
+ FAST_HIGHLIGHT[chroma-svn]=0
+ FAST_HIGHLIGHT[chroma-cvs]=0
+ FAST_HIGHLIGHT[chroma-aws]=0
+ FAST_HIGHLIGHT[chroma-yard]=0
+ FAST_HIGHLIGHT[chroma-cabal]=0
+ FAST_HIGHLIGHT[chroma-exercism]=0
+
+
 # Uncomment the following line to use case-sensitive completion.
 # CASE_SENSITIVE="true"