diff --git a/changelog.md b/changelog.md
new file mode 100644
--- /dev/null
+++ b/changelog.md
@@ -0,0 +1,29 @@
+#####   2.3 
+  include missing TestReplaceOpen 
+    
+#####   2.2 
+  MatchSame -> MatchHint    
+
+#####   2.1 
+  *API changes*
+
+  moved type files to Type dir   
+
+  ReplaceOpen accepts both MatchArray and PosLen
+    
+#####   2.0 
+  ReplaceOpen : add Text instance
+    
+#####   1.9 
+  add ReplaceOpen. ReplaceOpen can replace in various data types in addition to String, ByteString. 
+
+  ReplaceOpen itself does not regex. It only processes results as MatchArray. 
+
+  Replace calls regex, then passes results to ReplaceOpen which replaces
+    
+#####   1.8 
+  replace, replaceGroup -> replace
+
+#####   1.7 
+  add MatchSame
+                                   
diff --git a/regex-do.cabal b/regex-do.cabal
--- a/regex-do.cabal
+++ b/regex-do.cabal
@@ -1,5 +1,5 @@
 name:                regex-do
-version:             2.2
+version:             2.3
 synopsis:            PCRE wrapper
 description:         format, search, replace (String | ByteString) with PCRE regex. Utf8-safe
 author:              Imants Cekusins
@@ -7,6 +7,7 @@
 category:            Regex, Search, String
 license:             PublicDomain
 license-file:        PublicDomain
+extra-source-files:  changelog.md
 cabal-version:       >=1.10
 build-type:          Simple
 homepage:            https://github.com/ciez/regex-do
@@ -35,7 +36,6 @@
   other-modules:
           Text.Regex.Do.Pcre.Matchf
           Text.Regex.Do.Pcre.Result
-
   ghc-options:  -fwarn-unused-imports
     
   build-depends:  base <= 5.0,
@@ -83,6 +83,7 @@
         TestRegex.TestReplace
         TestRegex.TestSplit
         TestRegex.TestTrim
+        TestRegex.TestReplaceOpen
 
   build-depends:  base <= 5.0,
                   hspec,
diff --git a/src/Text/Regex/Do/Pcre/Match.hs b/src/Text/Regex/Do/Pcre/Match.hs
--- a/src/Text/Regex/Do/Pcre/Match.hs
+++ b/src/Text/Regex/Do/Pcre/Match.hs
@@ -1,4 +1,4 @@
--- | see "Text.Regex.Base.RegexLike"
+-- | see "Text.Regex.Base.RegexLike" and "Text.Regex.Do.Pcre.MatchHint"
 module Text.Regex.Do.Pcre.Match
     (Match(..),
     R.extract,   -- | 'extract' is reexport from "Text.Regex.Base.RegexLike"
@@ -20,7 +20,7 @@
     '=~' is borrowed from "Text.Regex.PCRE.Wrap",
     is a short version of 'match'
 
-    See also "Text.Regex.Do.Pcre.MatchSame"       -}
+    See also "Text.Regex.Do.Pcre.MatchHint"       -}
 
 class Match a b out where
     match::Pattern a -> Body b -> out
@@ -37,7 +37,7 @@
 
      \["all"\]
 
-     "Text.Regex.Do.Pcre.MatchSame"     -}
+     "Text.Regex.Do.Pcre.MatchHint"     -}
 instance Rx_ a b => Match a b Bool where
     match p0 (Body b0) = R.matchTest (r_ p0) b0
 {- ^ test
@@ -46,7 +46,7 @@
 
     True
 
-    "Text.Regex.Do.Pcre.MatchSame"      -}
+    "Text.Regex.Do.Pcre.MatchHint"      -}
 
 -- | match all
 instance Rx_ a b => Match a b [[b]] where
@@ -55,7 +55,7 @@
 
      \[["well"\],\["well"\]]
 
-     "Text.Regex.Do.Pcre.MatchSame"    -}
+     "Text.Regex.Do.Pcre.MatchHint"    -}
 
 -- | match once
 instance Rx_ a b => Match a b [PosLen] where
@@ -66,7 +66,7 @@
 
      /Utf8/
 
-     "Text.Regex.Do.Pcre.MatchSame"     -}
+     "Text.Regex.Do.Pcre.MatchHint"     -}
 
 -- | match all
 instance Rx_ a b => Match a b [[PosLen]] where
diff --git a/src/Text/Regex/Do/Pcre/MatchHint.hs b/src/Text/Regex/Do/Pcre/MatchHint.hs
--- a/src/Text/Regex/Do/Pcre/MatchHint.hs
+++ b/src/Text/Regex/Do/Pcre/MatchHint.hs
@@ -1,5 +1,15 @@
 {- | this module uses
     <https://cdepillabout.github.io/haskell-type-families-presentation/#/ TypeFamilies>
+
+    this module is similar to "Text.Regex.Do.Pcre.Match". The differences are:
+
+    "Text.Regex.Do.Pcre.Match" is more flexible:
+        accepts 'Pattern' Regex,
+        accepts 'Pattern' and 'Body' of different types
+
+    "Text.Regex.Do.Pcre.Match" needs to infer result type
+
+    in this module the result type is determined by the hint
     -}
 
 {-# LANGUAGE TypeFamilies #-}
@@ -18,6 +28,10 @@
 
     handy when working with 'OverloadedStrings', in other cases when compiler needs a hint
 
+    >>> Test ("в"::ByteString) =~ "тихо в лесу"
+
+    True
+
     >>> Once ("^all"::String) =~ "all the time"
 
     \["all"\]
@@ -31,9 +45,9 @@
     match::hint (Pattern a) -> Body a -> F hint a
     match h0 = M.match $ unhint h0
 
-    (=~)::hint a  -- ^ pattern
+    (=~)::hint a  -- ^ hint & pattern
             -> a          -- ^ body
-            -> F hint a        -- ^ \- in ('-~') is the minus sign
+            -> F hint a   -- ^ type defined by the instance, determined by the hint
     (=~) h0 = (M.=~) $ unhint h0
 
 
diff --git a/src/Text/Regex/Do/Type/MatchHint.hs b/src/Text/Regex/Do/Type/MatchHint.hs
--- a/src/Text/Regex/Do/Type/MatchHint.hs
+++ b/src/Text/Regex/Do/Type/MatchHint.hs
@@ -1,7 +1,6 @@
 module Text.Regex.Do.Type.MatchHint where
 
-
-newtype Test a = Test a
+newtype Test a = Test a     -- ^ test: does body match pattern?
 newtype Once a = Once a     -- ^ values
 newtype All a = All a       -- ^ values
 newtype PosLen' a = PosLen' a   -- ^ once
diff --git a/test/TestRegex/TestReplaceOpen.hs b/test/TestRegex/TestReplaceOpen.hs
new file mode 100644
--- /dev/null
+++ b/test/TestRegex/TestReplaceOpen.hs
@@ -0,0 +1,25 @@
+{-# LANGUAGE OverloadedStrings #-}
+module TestRegex.TestReplaceOpen where
+
+import Test.Hspec
+import Text.Regex.Do.Pcre.ReplaceOpen as O
+import Text.Regex.Do.Type.Do
+import Data.Text
+import Text.Regex.Do.Convert()
+import Debug.Trace
+
+
+main::IO()
+main = hspec $ do
+       describe "TestRegex.TestReplaceOpen" $ do
+          it "case 1" $
+            O.replace (Just [(4,3)::PosLen]) (Replacement "4567") (Body "abc 123 def"::Body Text) `shouldBe` ("abc 4567 def"::Text)
+          it "case 2" $
+            O.replace (Just ([(4,3),(8,2)]::[PosLen])) replacer (Body "abc 123 def"::Body Text) `shouldBe` ("abc [1-2-3] def"::Text)
+
+
+replacer::GroupReplacer Text
+replacer = defaultReplacer 1 tweak1
+          where tweak1 str1 = case str1 of
+                                "123" -> "[1-2-3]"
+                                otherwise -> traceShow str1 "?"