diff --git a/copilot-language.cabal b/copilot-language.cabal
--- a/copilot-language.cabal
+++ b/copilot-language.cabal
@@ -1,14 +1,25 @@
 cabal-version:       >=1.10
 name:                copilot-language
-version:             0.4
+version:             0.5
 synopsis:            A Haskell-embedded DSL for monitoring hard real-time
                      distributed systems.
-description:         Blah blah blah...
+description:
+  The concrete syntax for Copilot.
+  .
+  Copilot is a stream (i.e., infinite lists) domain-specific language (DSL) in
+  Haskell that compiles into embedded C.  Copilot contains an interpreter,
+  multiple back-end compilers, and other verification tools.  A tutorial, bug
+  reports, and todos are available at
+  <https://github.com/niswegmann/copilot-discussion>.  
+  .
+  Examples are available at
+  <https://github.com/leepike/Copilot/tree/master/Examples>.
+
 license:             BSD3
 license-file:        LICENSE
 author:              Lee Pike, Robin Morisset, Alwyn Goodloe, Sebastian Niller,
                      Nis Nordby Wegmann
-maintainer:          niswegmann@gmail.com
+maintainer:          leepike@gmail.com
 stability:           Experimental
 category:            Language, Embedded
 build-type:          Simple
diff --git a/src/Copilot/Language/Stream.hs b/src/Copilot/Language/Stream.hs
--- a/src/Copilot/Language/Stream.hs
+++ b/src/Copilot/Language/Stream.hs
@@ -64,7 +64,7 @@
 
 --------------------------------------------------------------------------------
 
-instance (Typed a, Num a) => Num (Stream a) where
+instance (Typed a, Eq a, Num a) => Num (Stream a) where
   (Const x) + (Const y)   = Const (x + y)
   (Const 0) + y           = y
   x + (Const 0)           = x