diff --git a/ChangeLog.md b/ChangeLog.md
index 0833aa8..51abaee 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+## [0.1.2.8] - 2020-03-12
+### Added
+- `instance Traversable (Sequence mk w)`.
+
 ## [0.1.2.7] - 2020-02-11
 ### Changed
 - Support GHC-8.8.
diff --git a/package.yaml b/package.yaml
index 2b12fec..7257dcc 100644
--- a/package.yaml
+++ b/package.yaml
@@ -1,8 +1,8 @@
 name:                cobot-io
-version:             0.1.2.7
+version:             0.1.2.8
 github:              "less-wrong/cobot-io"
 license:             BSD3
-category:            Bio 
+category:            Bio
 author:              "Pavel Yakovlev, Bogdan Neterebskii, Alexander Sadovnikov"
 maintainer:          "pavel@yakovlev.me"
 copyright:           "2018-2019, Less Wrong Bio"
@@ -57,7 +57,7 @@ library:
     - TypeOperators
     - TemplateHaskell
     - FlexibleContexts
-      
+
 
 tests:
   cobot-io-test:
diff --git a/src/Bio/Sequence/Class.hs b/src/Bio/Sequence/Class.hs
index bd5d74c..f183125 100644
--- a/src/Bio/Sequence/Class.hs
+++ b/src/Bio/Sequence/Class.hs
@@ -87,6 +87,9 @@ instance Foldable (Sequence mk w) where
 
   length = V.length . _sequ
 
+instance Traversable (Sequence mk w) where
+  traverse f s@Sequence{..} = fmap (\newSeq -> s { _sequ = newSeq }) $ traverse f _sequ
+
 -- | Exported constructor for 'Sequence'. Should be used ONLY in module Bio.Sequence.
 --
 _sequenceInner :: Vector a -> [(mk, Range)] -> Vector w -> Sequence mk w a