diff --git a/src/System/Random/Effect.hs b/src/System/Random/Effect.hs
--- a/src/System/Random/Effect.hs
+++ b/src/System/Random/Effect.hs
@@ -6,7 +6,13 @@
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE UndecidableInstances #-}
 -- | A random number effect, using a pure mersenne twister under
---   the hood. This should be plug-and-play with any application
+--   the hood. This algorithm is not suitable for cryptography!
+--
+--   If you need cryptographically secure random numbers,
+--   you MUST use 'mkSecureRandomIO'. Otherwise, 'mkRandom' and
+--   'mkRandomIO' are much faster.
+--
+--   This effect should be plug-and-play with any application
 --   making use of extensible effects.
 --
 --   Patches, even for the smallest of documentation bugs, are
diff --git a/system-random-effect.cabal b/system-random-effect.cabal
--- a/system-random-effect.cabal
+++ b/system-random-effect.cabal
@@ -1,5 +1,5 @@
 name:                  system-random-effect
-version:               0.4.1
+version:               0.4.1.1
 synopsis:              Random number generation for extensible effects.
 homepage:              https://github.com/wowus/system-random-effect
 license:               BSD3