diff --git a/README b/README
index 3c447b9..d5bc8c9 100644
--- a/README
+++ b/README
@@ -12,6 +12,7 @@ sqlite3 (>= 3.5.9)
 check (for tests)
 intltool
 python-docutils (for man pages)
+magic (optional)
 
 Please note that you need to have a working pkg-config installation and that the
 Makefile is only compatible with GNU make. If you don't have a working
@@ -26,6 +27,9 @@ WITH_SQLITE=0 and sqlite support won't be available. Please note that sqlite3
 with metadata support is required, i.e. sqlite3 has to be built with
 SQLITE_ENABLE_COLUMN_METADATA defined.
 
+The use of magic to detect mimetypes is optional and can be disabled by setting
+WITH_MAGIC=0.
+
 Installation
 ------------
 To build and install zathura: