diff --git a/Data/Bits/Atomic.hs b/Data/Bits/Atomic.hs
--- a/Data/Bits/Atomic.hs
+++ b/Data/Bits/Atomic.hs
@@ -1,8 +1,8 @@
 {-# LANGUAGE ForeignFunctionInterface #-}
 -- | Atomic bit operations, using GCC's built-in atomic operations in small C
 -- wrapper functions called through the FFI. See
--- <http://gcc.gnu.org/onlinedocs/gcc-4.5.0/gcc/Atomic-Builtins.html> or the
--- version corresponding to your compiler for more detail.
+-- <http://gcc.gnu.org/wiki/Atomic> and
+-- <http://gcc.gnu.org/onlinedocs/gcc/Atomic-Builtins.html> for more detail.
 module Data.Bits.Atomic (
     -- * Atomic bit operations on 'Word'-sized memory locations
     AtomicBits(..),
diff --git a/bits-atomic.cabal b/bits-atomic.cabal
--- a/bits-atomic.cabal
+++ b/bits-atomic.cabal
@@ -1,5 +1,5 @@
 Name:               bits-atomic
-Version:            0.1.2
+Version:            0.1.3
 License:            BSD3
 License-File:       License.txt
 Maintainer:         Gabriel Wicke <wicke@wikidev.net>
@@ -7,12 +7,24 @@
 Synopsis:       Atomic bit operations on memory locations 
                 for low-level synchronization
 Description:        
- Atomic operations including CAS (compare-and-swap), lock and fetch & add
+ Atomic operations including CAS (compare-and-swap), fetch & add and variants
  suitable for low-level shared-memory synchronization.
  .
- The implementation is using GCC's builtin atomic operations in C wrappers
- called through the FFI.
+ The implementation is using GCC's builtin atomic operations (available in GCC >=
+ 4) in C wrappers called through the FFI. See these links for background:
  .
+ * GCC manual: <http://gcc.gnu.org/onlinedocs/gcc/Atomic-Builtins.html>
+ .
+ * GCC wiki: <http://gcc.gnu.org/wiki/Atomic>
+ .
+ /Portability/: This package is primarily developed on a Linux system, but
+ should work wherever GCC >= 4 is available. It has been confirmed as working
+ on OSX. On Windows, it should work with Cygwin but currently fails for
+ vanilla Haskell-Platform 2010.1.0.0 as it still packages GCC 3.x. An
+ installer for updated versions of GCC is available at
+ <http://www.mingw.org/> and should make this package work in connection with
+ Haskell-Platform. Feedback on compatibility would be appreciated.
+ .
  /Testing:/ The following commands can be used to compile and run the test suite:
  .
     > cabal unpack bits-atomic && cd bits-atomic-* # if not yet locally available
@@ -21,6 +33,9 @@
     > cabal test
  .
  /Recent changes/:
+ .
+ * 0.1.3: Documentation updates, especially on portability. No functional
+   changes.
  .
  * 0.1.2: Avoid using System.FilePath in Setup.hs to fix build failure on hackage
 Category:           Data, Concurrency, Foreign