diff --git a/CMakeLists.txt b/CMakeLists.txt
index a6c3946..201b1ba 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -34,6 +34,11 @@ IF(LIBNFC_LOG)
   ADD_DEFINITIONS(-DLOG)
 ENDIF(LIBNFC_LOG)
 
+SET(LIBNFC_ENVVARS ON CACHE BOOL "Enable envvars facility")
+IF(LIBNFC_ENVVARS)
+  ADD_DEFINITIONS(-DENVVARS)
+ENDIF(LIBNFC_ENVVARS)
+
 SET(LIBNFC_DEBUG_MODE OFF CACHE BOOL "Debug mode")
 IF(LIBNFC_DEBUG_MODE)
   ADD_DEFINITIONS(-DDEBUG)