diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,22 +1,5 @@
-0.3.3.1
-===
-
-- removed doctest-parallel test suite, use cabal-docspec in CI instead
-- updated CI to use cabal-docspec 0.0.0.20250606
-
-0.3.3
-===
-
-- GHC 9.14.1 support
-- simplified Cabal stanzas to best practice template
-
-0.3.2
-===
-
-- added Data instances
-
+# Changelog
 
-0.3.1
-===
+## 0.3.4.0
 
-- added doctests
+- Added `Read` instances for `FStyle` and `FormatN`.
diff --git a/formatn.cabal b/formatn.cabal
--- a/formatn.cabal
+++ b/formatn.cabal
@@ -1,6 +1,6 @@
 cabal-version: 3.0
 name: formatn
-version: 0.3.3.1
+version: 0.3.4.0
 license: BSD-3-Clause
 license-file: LICENSE
 copyright: Tony Day (c) 2016
diff --git a/src/Data/FormatN.hs b/src/Data/FormatN.hs
--- a/src/Data/FormatN.hs
+++ b/src/Data/FormatN.hs
@@ -403,7 +403,7 @@
   | FSPrec
   | FSCommaPrec
   | FSNone
-  deriving (Eq, Show, Generic, Data)
+  deriving (Eq, Show, Read, Generic, Data)
 
 -- | Compute the majority (modal) FormatStyle so a list of numbers can all have the same formatting
 --
@@ -623,7 +623,7 @@
     addLPad :: Bool,
     cutRightZeros :: Bool
   }
-  deriving (Eq, Show, Generic, Data)
+  deriving (Eq, Show, Read, Generic, Data)
 
 -- | The official FormatN
 defaultFormatN :: FormatN