diff --git a/.circleci/config.yml b/.circleci/config.yml
index 840c0d0..209b570 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -1,7 +1,7 @@
 version: 2.1
 
 orbs:
-  haskell: haskell-works/haskell-build@1.6.2
+  haskell: haskell-works/haskell-build@dev:jky
   github: haskell-works/github-release@1.2.1
   hackage: haskell-works/hackage@1.0.0
   display: haskell-works/display@1.0.1
diff --git a/hw-json-simd.cabal b/hw-json-simd.cabal
index 5fd8fbe..438970c 100644
--- a/hw-json-simd.cabal
+++ b/hw-json-simd.cabal
@@ -47,6 +47,10 @@ flag sse42
 
 common base                   { build-depends: base                 >= 4          && < 5      }
 common bytestring             { build-depends: bytestring           >= 0.10.6     && < 0.11   }
+common hedgehog               { build-depends: hedgehog             >= 0.5        && < 0.7    }
+common hspec                  { build-depends: hspec                >= 2.4        && < 3      }
+common hw-bits                { build-depends: hw-bits              >= 0.7.0.5    && < 0.8    }
+common hw-hspec-hedgehog      { build-depends: hw-hspec-hedgehog    >= 0.1.0.4    && < 0.2    }
 common hw-prim                { build-depends: hw-prim              >= 0.6.2.21   && < 0.7    }
 common lens                   { build-depends: lens                 >= 4          && < 5      }
 common optparse-applicative   { build-depends: optparse-applicative >= 0.14       && < 0.15   }
@@ -122,6 +126,10 @@ executable hw-json-simd
 test-suite hw-json-simd-test
   import:   base, config
           , bytestring
+          , hedgehog
+          , hspec
+          , hw-bits
+          , hw-hspec-hedgehog
           , hw-prim
           , lens
           , semigroups
@@ -131,6 +139,7 @@ test-suite hw-json-simd-test
   main-is:          Spec.hs
   autogen-modules:  Paths_hw_json_simd
   other-modules:    Paths_hw_json_simd
+                    HaskellWorks.Data.Json.Simd.Index.StandardSpec
   hs-source-dirs:   test
   ghc-options:      -threaded -rtsopts -with-rtsopts=-N
   build-depends:    hw-json-simd
diff --git a/test/HaskellWorks/Data/Json/Simd/Index/StandardSpec.hs b/test/HaskellWorks/Data/Json/Simd/Index/StandardSpec.hs
new file mode 100644
index 0000000..0b6763a
--- /dev/null
+++ b/test/HaskellWorks/Data/Json/Simd/Index/StandardSpec.hs
@@ -0,0 +1,83 @@
+{-# LANGUAGE FlexibleContexts  #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+module HaskellWorks.Data.Json.Simd.Index.StandardSpec
+  ( spec
+  ) where
+
+import Data.Semigroup                 ((<>))
+import HaskellWorks.Data.Bits.BitShow
+import HaskellWorks.Hspec.Hedgehog
+import Hedgehog
+import Test.Hspec
+
+import qualified Data.ByteString                            as BS
+import qualified Data.ByteString.Lazy                       as LBS
+import qualified HaskellWorks.Data.ByteString.Lazy          as LBS
+import qualified HaskellWorks.Data.Json.Simd.Index.Standard as SI
+
+{-# ANN module ("HLint: ignore Redundant do"        :: String) #-}
+
+makeStandardJsonIbs :: LBS.ByteString -> BS.ByteString
+makeStandardJsonIbs bs = let Right chunks = fmap fst <$> SI.makeStandardJsonIbBps (LBS.resegmentPadded 512 bs) in mconcat chunks
+
+makeStandardJsonBps :: LBS.ByteString -> BS.ByteString
+makeStandardJsonBps bs = let Right chunks = fmap snd <$> SI.makeStandardJsonIbBps (LBS.resegmentPadded 512 bs) in mconcat chunks
+
+spec :: Spec
+spec = describe "HaskellWorks.Data.Json.Succinct.Cursor.InterestBitsSpec" $ do
+  it "Evaluating interest bits" $ requireTest $ do
+    bitShow (makeStandardJsonBps ""           ) === ""
+    bitShow (makeStandardJsonBps "  \n \r \t ") === ""
+    bitShow (makeStandardJsonBps "1234 "      ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "1.1 "       ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "-1.1e-1 "   ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "false "     ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "true "      ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "\"hello\" " ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "\"\\\"\" "  ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "{ "         ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "} "         ) === "00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "[ "         ) === "10000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps "] "         ) === "00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps ": "         ) === ""
+    bitShow (makeStandardJsonBps ", "         ) === ""
+    bitShow (makeStandardJsonBps "{{}}"       ) === "11000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonBps " { { } } "  ) === "11000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+  it "Evaluating interest bits" $ requireTest $ do
+    bitShow (makeStandardJsonIbs ""           ) === ""
+    bitShow (makeStandardJsonIbs "  \n \r \t ") === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "1234 "      ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "1.1 "       ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "-1.1e-2 "   ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "false "     ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "true "      ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "\"hello\" " ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "\"\\\"\" "  ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "{ "         ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "} "         ) === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "[ "         ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "] "         ) === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs ": "         ) === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs ", "         ) === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "{{}}"       ) === "11000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs " { { } } "  ) === "01010000" <> mconcat (replicate 63 " 00000000")
+  it "Evaluating interest bits 2" $ requireTest $ do
+    bitShow (makeStandardJsonIbs ""           ) === ""
+    -- bitShow (makeStandardJsonIbs "  \n \r \t ") === "00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000"
+    bitShow (makeStandardJsonIbs "1234 "      ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "1.1 "       ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "-1.1 "      ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "-1.1e-2 "   ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "false "     ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "true "      ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "\"hello\" " ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "\"\\\"\" "  ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "{ "         ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "} "         ) === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "[ "         ) === "10000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "] "         ) === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs ": "         ) === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs ", "         ) === "00000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs "{{}}"       ) === "11000000" <> mconcat (replicate 63 " 00000000")
+    bitShow (makeStandardJsonIbs " { { } } "  ) === "01010000" <> mconcat (replicate 63 " 00000000")
diff --git a/test/Spec.hs b/test/Spec.hs
index cd4753f..a824f8c 100644
--- a/test/Spec.hs
+++ b/test/Spec.hs
@@ -1,2 +1 @@
-main :: IO ()
-main = putStrLn "Test suite not yet implemented"
+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}