diff --git a/circuit/slot_main.circom b/circuit/slot_main.circom
index 6dd9d1d..a2357bb 100644
--- a/circuit/slot_main.circom
+++ b/circuit/slot_main.circom
@@ -1,3 +1,3 @@
 pragma circom 2.0.0;
 include "sample_cells.circom";
-component main {public [entropy,slotRoot]} = SampleAndProveV1(1024, 9, 20);
+component main {public [entropy,slotRoot]} = SampleAndProveV1(1024, 5, 10);
diff --git a/reference/haskell/Sampling.hs b/reference/haskell/Sampling.hs
index f0c3ef3..4395490 100644
--- a/reference/haskell/Sampling.hs
+++ b/reference/haskell/Sampling.hs
@@ -13,10 +13,10 @@ import qualified ZK.Algebra.Curves.BN128.Fr.Mont as Fr
 
 --------------------------------------------------------------------------------
 
-samplingTest :: FilePath -> IO ()
-samplingTest fpath = do
+samplingTest :: SlotConfig -> FilePath -> IO ()
+samplingTest slotCfg fpath = do
   let entropy = 123456789 :: Fr
-  input <- calculateCircuitInput exSlotCfg entropy
+  input <- calculateCircuitInput slotCfg entropy
   exportCircuitInput fpath input
 
 --------------------------------------------------------------------------------
@@ -59,15 +59,18 @@ calculateCircuitInput slotCfg entropy = do
 -- | Export the inputs of the storage proof circuits in JSON format,
 -- which @circom@ can consume.
 --
+-- NOTE: large numbers (field elements) must be encoded as JSON strings,
+-- not numbers, as Javascript cannot handle large numbers!
+--
 exportCircuitInput :: FilePath -> CircuitInput -> IO ()
 exportCircuitInput fpath input = do
   h <- openFile fpath WriteMode
-  hPutStrLn h $ "{ \"entropy\":  " ++ show (_entropy  input)
-  hPutStrLn h $ ", \"slotRoot\": " ++ show (_slotRoot input)
+  hPutStrLn h $ "{ \"entropy\":  " ++ show (show (_entropy  input))
+  hPutStrLn h $ ", \"slotRoot\": " ++ show (show (_slotRoot input))
   hPutStrLn h $ ", \"cellData\": " 
-  hPrintListOfLists h (_cellData input)
+  hPrintListOfLists h ((map.map) show $ _cellData input)
   hPutStrLn h $ ", \"merklePaths\": " 
-  hPrintListOfLists h (_merklePaths input)
+  hPrintListOfLists h ((map.map) show $ _merklePaths input)
   hPutStrLn h $ "}"
   hClose h
 
@@ -86,7 +89,7 @@ hPrintList' h indentation xs = do
   hPutStrLn h (indentation False ++ "]")
 
 hPrintList :: Show a => Handle -> Int -> [a] -> IO ()
-hPrintList h indentBy xs = hPrintList' h (\_ -> indent indentBy) xs
+hPrintList h indentBy xs = hPrintList' h (\_ -> indent indentBy) $ xs
 
 hPrintListOfLists :: Show a => Handle -> [[a]] -> IO ()
 hPrintListOfLists h xss = 
diff --git a/reference/haskell/Slot.hs b/reference/haskell/Slot.hs
index 89be6d8..dfcaf64 100644
--- a/reference/haskell/Slot.hs
+++ b/reference/haskell/Slot.hs
@@ -52,8 +52,8 @@ fieldElemsPerCell cfg = (_cellSize cfg + 30) `div` 31
 --
 -- > template SampleAndProveV1( nCells, nFieldElemsPerCell, nSamples ) { ... }
 --
-circomMainComponentV1 :: FilePath -> SlotConfig -> IO ()
-circomMainComponentV1 circomFile slotCfg = do
+circomMainComponentV1 :: SlotConfig -> FilePath -> IO ()
+circomMainComponentV1 slotCfg circomFile = do
 
   let params =          show (_nCells           slotCfg)
              ++ ", " ++ show (fieldElemsPerCell slotCfg)
diff --git a/reference/haskell/testMain.hs b/reference/haskell/testMain.hs
index 36b8718..a82e3ef 100644
--- a/reference/haskell/testMain.hs
+++ b/reference/haskell/testMain.hs
@@ -4,8 +4,16 @@ module Main where
 import Slot
 import Sampling 
 
+mySlotCfg :: SlotConfig
+mySlotCfg = MkSlotCfg
+  { _cellSize = 128
+  , _nCells   = 1024
+  , _nSamples = 10
+  , _dataSrc  = FakeData 12345
+  }
+
 main :: IO ()
 main = do
-  let slotCfg = exSlotCfg
-  circomMainComponentV1 "slot_main.circom" slotCfg
-  samplingTest "input_example.json"
\ No newline at end of file
+  let slotCfg = mySlotCfg
+  circomMainComponentV1 slotCfg "slot_main.circom" 
+  samplingTest          slotCfg "input_example.json"
\ No newline at end of file