diff --git a/dev.hs b/dev.hs
index 281cd7333..234b5286a 100644
--- a/dev.hs
+++ b/dev.hs
@@ -1,27 +1,130 @@
 -- dev.hs, for miscellaneous profiling/benchmarking/testing.
 
-import Hledger.Utils.Debug
+-- {-# LANGUAGE DeriveDataTypeable, StandaloneDeriving, DeriveGeneric #-}
+-- {-# LANGUAGE NoWarnUnusedImports #-}
+
 -- import System.Environment (getArgs)
-import Control.Monad.Except
+-- import Control.Monad.Except
 import Criterion.Main
 -- import Data.Text.Lazy as LT
 -- import System.Environment
--- import Hledger
+import System.TimeIt      (timeItT)
+import Text.Printf
+
+import Hledger
+-- import Hledger.Utils.Regex (toRegexCI)
+-- import Hledger.Utils.Debug
 -- import qualified Hledger.Read.JournalReader as JR
-import qualified Hledger.Read.TimelogReader as TR
+-- import qualified Hledger.Read.TimelogReader as TR
 -- import qualified Hledger.Read.TimelogReaderNoJU as TRNOJU
 -- import qualified Hledger.Read.TimelogReaderPP as TRPP
 
-inputjournal = "data/10000x1000x10.journal"
-inputtimelog = "data/sample.timelog"
+-- import Control.DeepSeq (NFData)
+-- import Data.Data
+-- import GHC.Generics (Generic)
+-- import Text.Regex.TDFA (Regex(..))
+--
+-- instance Generic Regex
+-- instance NFData Regex
+-- deriving instance Data (Regex)
+-- deriving instance Typeable (Regex)
+-- deriving instance Generic (Regex)
+-- instance NFData Regex
+
+journal =
+  -- "data/10000x1000x10.journal"
+  "data/10000x1000x10.journal"
+
+timelog = "data/sample.timelog"
+
+timeit :: String -> IO a -> IO (Double, a)
+timeit name action = do
+  printf "%s%s" name (replicate (40 - length name) ' ')
+  (t,a) <- timeItT action
+  printf "[%.2fs]\n" t
+  return (t,a)
+
+timeReadJournal :: String -> String -> IO (Double, Journal)
+timeReadJournal msg s = timeit msg $ either error id <$> readJournal Nothing Nothing True Nothing s
 
 main = do
-  --  
+  -- putStrLn $ regexReplaceCI "^aa" "xx" "aa:bb:cc:dd:ee"
 
   -- -- read the input journal
-  -- j <- either error id <$> readJournalFile Nothing Nothing True inputfile
-  -- -- sanity check we parsed it all
-  -- putStrLn $ show $ length $ jtxns j
+  s <- readFile journal
+  j <- either error id <$> readJournal Nothing Nothing True Nothing s
+  -- putStrLn $ show $ length $ jtxns j -- sanity check we parsed it all
+  let accts = map paccount $ journalPostings j
+
+  Criterion.Main.defaultMainWith defaultConfig $ [
+    --  bench ("toRegexCI") $ whnf toRegexCI "^aa"
+    -- ,bench ("toRegexCI") $ whnfIO (return $ toRegexCI "^aa")
+    -- ,bench ("toRegexCI x 1000") $ nfIO $ sequence_ (map (return . toRegexCI) (replicate 1000 "^aa"))
+    --  bench ("regexReplaceCI")             $ nf (regexReplaceCI "aa" "xx") "aa:bb:cc:dd:ee:1"
+    -- ,bench ("regexReplaceCI x 1000")      $ nf (map (regexReplaceCI "bb" "xx")) (replicate 1000 "aa:bb:cc:dd:ee;2")
+    -- ,bench ("regexReplaceCIMemo")         $ nf (regexReplaceCIMemo "ee" "xx") "aa:bb:cc:dd:ee:5"
+    -- ,bench ("regexReplaceCIMemo x 1000")  $ nf (map (regexReplaceCIMemo "ff" "xx")) (replicate 1000 "aa:bb:cc:dd:ee:6")
+     bench ("apply one regex alias to one posting") $
+       nf (map (accountNameApplyAliases [RegexAlias "^1:" "x:"])) (map paccount $ take 1 $ journalPostings j)
+    -- ,bench ("apply one regex alias to 20000 postings") $
+    --    nf (map (accountNameApplyAliases [RegexAlias "^1:" "x:"])) (map paccount $ journalPostings j)
+    -- ,bench ("apply 3 regex aliases to 20000 postings") $
+    --    nf (map (accountNameApplyAliases [
+    --                 RegexAlias "^1:" "x:"
+    --                ,RegexAlias "^2:" "x:"
+    --                ,RegexAlias "^3:" "x:"
+    --                ])) accts
+
+    -- ,bench ("readJournal") $ whnfIO $
+    --    either error id <$>
+    --    readJournal Nothing Nothing True Nothing s
+    -- ,bench ("readJournal with aliases") $ whnfIO $
+    --    either error id <$>
+    --    readJournal Nothing Nothing True Nothing (
+    --      unlines [
+    --         "alias /^fb:/=xx \n"
+    --         ,"alias /^f1:/=xx \n"
+    --         ,"alias /^e7:/=xx \n"
+    --         ] ++ s)
+
+    ]
+
+  -- (t0,j0) <- timeReadJournal ("read "++journal) s
+  -- (t0',j0') <- timeReadJournal ("read "++journal++" again") s
+  -- (t1,j1) <- timeReadJournal ("read "++journal++"with 3 simple aliases")
+  --            (unlines [
+  --                "alias fb=xx \n"
+  --                ,"alias f1=xx \n"
+  --                ,"alias e7=xx \n"
+  --                ] ++ s)
+  -- (t1',j1') <- timeReadJournal ("read "++journal++"with 3 simple aliases again")
+  --            (unlines [
+  --                "alias fb=xx \n"
+  --                ,"alias f1=xx \n"
+  --                ,"alias e7=xx \n"
+  --                ] ++ s)
+  -- (t2,j2) <- timeReadJournal ("read "++journal++"with 3 regex aliases")
+  --            (unlines [
+  --                "alias /^fb:/=xx \n"
+  --                ,"alias /^f1:/=xx \n"
+  --                ,"alias /^e7:/=xx \n"
+  --                ] ++ s)
+  -- (t2',j2') <- timeReadJournal ("read "++journal++"with 3 regex aliases again")
+  --            (unlines [
+  --                "alias /^fb:/=xx \n"
+  --                -- ,"alias /^f1:/=xx \n"
+  --                -- ,"alias /^e7:/=xx \n"
+  --                ] ++ s)
+  -- putStrLn $ show (
+  --   -- j0,
+  --   -- j0',
+  --   -- j1,
+  --   -- j1',
+  --   -- j2,
+  --   j2'
+  --   ) -- force evaluation, though it seems not to be needed
+
+  -- return ()
 
   -- benchmark timelog parsing
   -- s <- readFile inputtimelog