diff --git a/.travis.yml b/.travis.yml
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,64 +1,87 @@
-# NB: don't set `language: haskell` here
+language: c
+sudo: false
 
-# The following enables several GHC versions to be tested; often it's enough to test only against the last release in a major GHC version. Feel free to omit lines listings versions you don't need/want testing for.
-env:
-# - CABALVER=1.16 GHCVER=6.12.3
-# - CABALVER=1.16 GHCVER=7.0.1
-# - CABALVER=1.16 GHCVER=7.0.2
-# - CABALVER=1.16 GHCVER=7.0.3
-# - CABALVER=1.16 GHCVER=7.0.4
-# - CABALVER=1.16 GHCVER=7.2.1
-# - CABALVER=1.16 GHCVER=7.2.2
-# - CABALVER=1.16 GHCVER=7.4.1
- - CABALVER=1.16 GHCVER=7.4.2
-# - CABALVER=1.16 GHCVER=7.6.1
-# - CABALVER=1.16 GHCVER=7.6.2
- - CABALVER=1.18 GHCVER=7.6.3
-# - CABALVER=1.18 GHCVER=7.8.1  # see note about Alex/Happy for GHC >= 7.8
-# - CABALVER=1.18 GHCVER=7.8.2
- - CABALVER=1.18 GHCVER=7.8.3
- - CABALVER=1.22 GHCVER=7.10.1
-# - CABALVER=head GHCVER=head   # see section about GHC HEAD snapshots
+cache:
+  directories:
+    - $HOME/.cabsnap
+    - $HOME/.cabal/packages
 
+before_cache:
+  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/build-reports.log
+  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/00-index.tar
+
 matrix:
-  allow_failures:
-   - env: CABALVER=1.22 GHCVER=7.10.1
+  include:
+    - env: CABALVER=1.18 GHCVER=7.6.3
+      compiler: ": #GHC 7.6.3"
+      addons: {apt: {packages: [cabal-install-1.18,ghc-7.6.3,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
+    - env: CABALVER=1.18 GHCVER=7.8.3 COVERAGE=1
+      compiler: ": #GHC 7.8.3"
+      addons: {apt: {packages: [cabal-install-1.18,ghc-7.8.3,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
+    - env: CABALVER=1.22 GHCVER=7.10.3
+      compiler: ": #GHC 7.10.3"
+      addons: {apt: {packages: [cabal-install-1.22,ghc-7.10.3,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
+    - env: CABALVER=1.24 GHCVER=8.0.1
+      compiler: ": #GHC 8.0.1"
+      addons: {apt: {packages: [cabal-install-1.24,ghc-8.0.1,alex-3.1.4,happy-1.19.5], sources: [hvr-ghc]}}
 
-# Note: the distinction between `before_install` and `install` is not important.
 before_install:
- - travis_retry sudo add-apt-repository -y ppa:hvr/ghc
- - travis_retry sudo apt-get update
- - travis_retry sudo apt-get install cabal-install-$CABALVER ghc-$GHCVER # see note about happy/alex
- - export PATH=/opt/ghc/$GHCVER/bin:/opt/cabal/$CABALVER/bin:$PATH
- - |
-   if [ $GHCVER = "head" ] || [ ${GHCVER%.*} = "7.8" ] || [ ${GHCVER%.*} = "7.10" ]; then
-     travis_retry sudo apt-get install happy-1.19.4 alex-3.1.3
-     export PATH=/opt/alex/3.1.3/bin:/opt/happy/1.19.4/bin:$PATH
-   else
-     travis_retry sudo apt-get install happy alex
-   fi
+ - unset CC
+ - export PATH=/opt/ghc/$GHCVER/bin:/opt/cabal/$CABALVER/bin:/opt/alex/3.1.4/bin:/opt/happy/1.19.5/bin:~/.cabal/bin:$PATH
 
 install:
  - cabal --version
  - echo "$(ghc --version) [$(ghc --print-project-git-commit-id 2> /dev/null || echo '?')]"
- - travis_retry cabal update
- - cabal install --only-dependencies --enable-tests --enable-benchmarks
+ - if [ -f $HOME/.cabal/packages/hackage.haskell.org/00-index.tar.gz ];
+   then
+     zcat $HOME/.cabal/packages/hackage.haskell.org/00-index.tar.gz >
+          $HOME/.cabal/packages/hackage.haskell.org/00-index.tar;
+   fi
+ - travis_retry cabal update -v
+ - sed -i 's/^jobs:/-- jobs:/' ${HOME}/.cabal/config
+ - cabal install --only-dependencies --enable-tests --enable-benchmarks --dry -v > installplan.txt
+ - sed -i -e '1,/^Resolving /d' installplan.txt; cat installplan.txt
 
-# Here starts the actual work to be performed for the package under test; any command which exits with a non-zero exit code causes the build to fail.
+# check whether current requested install-plan matches cached package-db snapshot
+ - if diff -u installplan.txt $HOME/.cabsnap/installplan.txt;
+   then
+     echo "cabal build-cache HIT";
+     rm -rfv .ghc;
+     cp -a $HOME/.cabsnap/ghc $HOME/.ghc;
+     cp -a $HOME/.cabsnap/lib $HOME/.cabsnap/share $HOME/.cabsnap/bin $HOME/.cabal/;
+   else
+     echo "cabal build-cache MISS";
+     rm -rf $HOME/.cabsnap;
+     mkdir -p $HOME/.ghc $HOME/.cabal/lib $HOME/.cabal/share $HOME/.cabal/bin;
+     cabal install --only-dependencies --enable-tests --enable-benchmarks;
+   fi
+
+# snapshot package-db on cache miss
+ - if [ ! -d $HOME/.cabsnap ];
+   then
+      echo "snapshotting package-db to build-cache";
+      mkdir $HOME/.cabsnap;
+      cp -a $HOME/.ghc $HOME/.cabsnap/ghc;
+      cp -a $HOME/.cabal/lib $HOME/.cabal/share $HOME/.cabal/bin installplan.txt $HOME/.cabsnap/;
+   fi
+
+# Here starts the actual work to be performed for the package under test;
+# any command which exits with a non-zero exit code causes the build to fail.
 script:
  - if [ -f configure.ac ]; then autoreconf -i; fi
- - cabal configure --enable-tests --enable-benchmarks -v2  # -v2 provides useful information for debugging
+ - cabal configure --enable-tests --enable-benchmarks -v2 $([ "$COVERAGE" = "1" ] && echo "--enable-library-coverage") # -v2 provides useful information for debugging
  - cabal build   # this builds all libraries and executables (including tests/benchmarks)
  - cabal test
  - cabal check
  - cabal sdist   # tests that a source-distribution can be generated
 
-# The following scriptlet checks that the resulting source distribution can be built & installed
- - export SRC_TGZ=$(cabal info . | awk '{print $2 ".tar.gz";exit}') ;
-   cd dist/;
-   if [ -f "$SRC_TGZ" ]; then
-      cabal install --force-reinstalls "$SRC_TGZ";
-   else
-      echo "expected '$SRC_TGZ' not found";
-      exit 1;
-   fi
+# Check that the resulting source distribution can be built & installed.
+# If there are no other `.tar.gz` files in `dist`, this can be even simpler:
+# `cabal install --force-reinstalls dist/*-*.tar.gz`
+ - SRC_TGZ=$(cabal info . | awk '{print $2;exit}').tar.gz &&
+   (cd dist && cabal install --force-reinstalls "$SRC_TGZ")
+
+# This block must be executed before before_cache
+#after_script:
+ - "[ -n \"$COVERAGE\" ] && cabal install hpc-coveralls --avoid-reinstalls --constraint=\"regex-posix >=0.95.2\" || true" # regex-posix-0.95.1 has compilation problem
+ - "[ -n \"$COVERAGE\" ] && hpc-coveralls TestExtendedReal --exclude-dir=test || true"
diff --git a/extended-reals.cabal b/extended-reals.cabal
--- a/extended-reals.cabal
+++ b/extended-reals.cabal
@@ -1,5 +1,5 @@
 name:                extended-reals
-version:             0.2.1.0
+version:             0.2.2.0
 synopsis:            Extension of real numbers with positive/negative infinities
 description:
   Extension of real numbers with positive/negative infinities (±∞).
@@ -30,7 +30,7 @@
   Type:              exitcode-stdio-1.0
   HS-Source-Dirs:    test
   Main-is:           TestExtendedReal.hs
-  Build-depends:     base, HUnit >=1.2 && <1.3, QuickCheck >=2.6 && <2.8, test-framework >=0.8 && <0.9, test-framework-th >=0.2 && <0.3, test-framework-hunit >=0.3 && <0.4, test-framework-quickcheck2 >=0.3 && <0.4, extended-reals
+  Build-depends:     base, deepseq, HUnit >=1.2 && <1.4, QuickCheck >=2.6 && <2.9, test-framework >=0.8 && <0.9, test-framework-th >=0.2 && <0.3, test-framework-hunit >=0.3 && <0.4, test-framework-quickcheck2 >=0.3 && <0.4, extended-reals
   Default-Language: Haskell2010
   Other-Extensions:
      TemplateHaskell
diff --git a/test/TestExtendedReal.hs b/test/TestExtendedReal.hs
--- a/test/TestExtendedReal.hs
+++ b/test/TestExtendedReal.hs
@@ -2,12 +2,14 @@
 {-# LANGUAGE TemplateHaskell, ScopedTypeVariables #-}
 
 import Prelude hiding (isInfinite)
+import Control.DeepSeq
 import Control.Exception (SomeException, evaluate, try)
 import Control.Monad
 import Data.Maybe
 import System.IO.Unsafe (unsafePerformIO)
 import Test.HUnit hiding (Test)
 import Test.QuickCheck
+import Test.QuickCheck.Function
 import Test.Framework.TH
 import Test.Framework.Providers.HUnit
 import Test.Framework.Providers.QuickCheck2
@@ -137,15 +139,56 @@
 case_recip_NegInf :: IO ()
 case_recip_NegInf = recip (- inf) @?= (0 :: Extended Rational)
 
-prop_NegInf_smallest :: Property
-prop_NegInf_smallest =
+prop_minBound_smallest :: Property
+prop_minBound_smallest =
   forAll arbitrary $ \(a :: Extended Rational) ->
-    -inf <= a
+    minBound <= a
 
-prop_PosInf_largest :: Property
-prop_PosInf_largest =
+prop_maxBound_largest :: Property
+prop_maxBound_largest =
   forAll arbitrary $ \(a :: Extended Rational) ->
-    a <= inf
+    a <= maxBound
+
+prop_isFinite_fromRational :: Property
+prop_isFinite_fromRational =
+  forAll arbitrary $ \a -> isFinite (fromRational a :: Extended Rational)
+
+prop_isInfinite_PosInf :: Property
+prop_isInfinite_PosInf = property $ isInfinite PosInf
+
+prop_isInfinite_NegInf :: Property
+prop_isInfinite_NegInf = property $ isInfinite NegInf
+
+-- ----------------------------------------------------------------------
+-- Functor
+
+prop_Functor_id :: Property
+prop_Functor_id =
+  forAll arbitrary $ \(a :: Extended Integer) ->
+    fmap id a == a
+
+prop_Functor_comp :: Property
+prop_Functor_comp =
+  forAll arbitrary $ \(f :: Fun Integer Integer) ->
+  forAll arbitrary $ \(g :: Fun Integer Integer) ->
+  forAll arbitrary $ \(a :: Extended Integer) ->
+    fmap (apply f . apply g) a == fmap (apply f) (fmap (apply g) a)
+
+-- ----------------------------------------------------------------------
+-- Show / Read
+
+prop_read_show :: Property
+prop_read_show =
+  forAll arbitrary $ \(a :: Extended Rational) ->
+    read (show a) == a
+
+-- ----------------------------------------------------------------------
+-- deepseq
+
+prop_deepseq :: Property
+prop_deepseq =
+  forAll arbitrary $ \(a :: Extended Rational) ->
+    a `deepseq` () == ()
 
 -- ----------------------------------------------------------------------
 -- Test harness