diff --git a/ihaskell-widgets.cabal b/ihaskell-widgets.cabal
--- a/ihaskell-widgets.cabal
+++ b/ihaskell-widgets.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.2.2.1
+version:             0.2.3.1
 
 -- A short (one-line) description of the package.
 synopsis:            IPython standard widgets for IHaskell.
@@ -95,20 +95,26 @@
   -- other-extensions:    
   
   -- Other library packages from which modules are imported.
-  build-depends:       aeson >=0.7 && < 0.11
+  -- singletons 2.* require ghc 7.10.2
+  build-depends:       aeson >=0.7 && < 0.12
                      , base >=4.7 && <4.9
                      , containers >= 0.5
                      , ipython-kernel >= 0.6.1.2
                      , text >= 0.11
                      , unordered-containers -any
-                     , nats -any
                      , vinyl >= 0.5
                      , vector -any
-                     , singletons >= 0.9.0 && <2.0.0.0
                      , scientific -any
                      , unix -any
-
                      , ihaskell >= 0.6.4.1
+  if impl(ghc >= 7.10.2)
+    build-depends:       singletons >= 0.9.0
+  if impl(ghc == 7.10.1)
+    build-depends:       singletons >= 0.9.0 && <2.0
+                       , nats -any
+  if impl(ghc < 7.10.1)
+    build-depends:       singletons >= 0.9.0 && <2.0
+                       , nats <1.1
   
   -- Directories containing source files.
   hs-source-dirs:      src
@@ -123,3 +129,8 @@
   --   ghc-7.10.* = 100
   if impl(ghc == 7.8.*)
     ghc-options:       -fcontext-stack=100
+
+  -- compile without optimizations not to run out of memory on travis
+  if impl(ghc == 7.10.*)
+    ghc-options:       -O0
+
diff --git a/src/IHaskell/Display/Widgets/Singletons.hs b/src/IHaskell/Display/Widgets/Singletons.hs
--- a/src/IHaskell/Display/Widgets/Singletons.hs
+++ b/src/IHaskell/Display/Widgets/Singletons.hs
@@ -5,10 +5,13 @@
 {-# LANGUAGE UndecidableInstances #-}
 {-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE InstanceSigs #-}
 
 module IHaskell.Display.Widgets.Singletons where
 
 import           Data.Singletons.TH
+import           Data.Singletons.Prelude.Ord
 
 -- Widget properties
 singletons