diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+## [0.1.2.7] - 2020-02-11
+### Changed
+- Support GHC-8.8.
+
 ## [0.1.2.6] - 2019-12-12
 ### Fixed
 - Fixes for instance of `StructureModels` for `Mae` when working with structures without explicit chain names.
diff --git a/cobot-io.cabal b/cobot-io.cabal
--- a/cobot-io.cabal
+++ b/cobot-io.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 0f03c19b37ba0793d464c62245414745d11715571fb56535d09dedf96fc5f683
+-- hash: b98bae8044cc69e013da5d57a2077a7d9b4f9330def6ecd281f524600c734fa9
 
 name:           cobot-io
-version:        0.1.2.6
+version:        0.1.2.7
 synopsis:       Biological data file formats and IO
 description:    Please see the README on GitHub at <https://github.com/less-wrong/cobot-io#readme>
 category:       Bio
diff --git a/src/Bio/FASTA.hs b/src/Bio/FASTA.hs
--- a/src/Bio/FASTA.hs
+++ b/src/Bio/FASTA.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module Bio.FASTA
   ( module T
   , fromFile
@@ -6,16 +8,21 @@
   ) where
 
 import           Bio.FASTA.Parser
-import           Bio.FASTA.Type             as T
-import           Bio.FASTA.Writer           (fastaToText)
-import           Control.Monad.IO.Class     (MonadIO, liftIO)
-import           Data.Attoparsec.Text       (parseOnly)
-import           Data.Text.IO               (readFile, writeFile)
-import           Prelude            hiding  (writeFile, readFile)
+import           Bio.FASTA.Type         as T
+import           Bio.FASTA.Writer       (fastaToText)
+import           Control.Monad.IO.Class (MonadIO, liftIO)
+import           Data.Attoparsec.Text   (parseOnly)
+import           Data.Text.IO           (readFile, writeFile)
+#if !MIN_VERSION_base(4,13,0)
+import           Control.Monad.Fail     (MonadFail (..))
+import           Prelude                hiding (fail, readFile, writeFile)
+#else
+import           Prelude                hiding (readFile, writeFile)
+#endif
 
 -- | Reads 'FastaSequence' from given file.
 --
-fromFile :: MonadIO m => FilePath -> m (Fasta Char)
+fromFile :: (MonadFail m, MonadIO m) => FilePath -> m (Fasta Char)
 fromFile f = liftIO (readFile f) >>= either fail pure . parseOnly fastaP
 
 -- | Writes 'FastaSequence' to file.
diff --git a/src/Bio/GB.hs b/src/Bio/GB.hs
--- a/src/Bio/GB.hs
+++ b/src/Bio/GB.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module Bio.GB
   ( module T
   , fromFile
@@ -15,10 +17,14 @@
 import           Data.Bifunctor         (first)
 import           Data.Text              (Text, pack)
 import qualified Data.Text.IO           as TIO (readFile, writeFile)
+#if !MIN_VERSION_base(4,13,0)
+import           Control.Monad.Fail     (MonadFail(..))
+import           Prelude                hiding (fail)
+#endif
 
 -- | Reads 'GenBankSequence' from givem file.
 --
-fromFile :: MonadIO m => FilePath -> m GenBankSequence
+fromFile :: (MonadFail m, MonadIO m) => FilePath -> m GenBankSequence
 fromFile f = liftIO (TIO.readFile f) >>= either fail pure . parseOnly genBankP
 
 -- | Writes 'GenBankSequence' to file.
diff --git a/src/Bio/MAE.hs b/src/Bio/MAE.hs
--- a/src/Bio/MAE.hs
+++ b/src/Bio/MAE.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE AllowAmbiguousTypes #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
@@ -34,10 +35,14 @@
 import           Data.Vector            (Vector)
 import qualified Data.Vector            as V (fromList)
 import           Linear.V3              (V3 (..))
+#if !MIN_VERSION_base(4,13,0)
+import           Control.Monad.Fail     (MonadFail(..))
+import           Prelude                hiding (fail)
+#endif
 
 -- | Reads 'Mae' from givem file.
 --
-fromFile :: MonadIO m => FilePath -> m Mae
+fromFile :: (MonadFail m, MonadIO m) => FilePath -> m Mae
 fromFile f = liftIO (TIO.readFile f) >>= either fail pure . parseOnly maeP
 
 -- | Reads 'Mae' from 'Text'.
diff --git a/src/Bio/MMTF.hs b/src/Bio/MMTF.hs
--- a/src/Bio/MMTF.hs
+++ b/src/Bio/MMTF.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 module Bio.MMTF
   ( module Bio.MMTF.Type
@@ -22,14 +24,18 @@
 import           Data.Vector            (Vector, empty, toList, (!))
 import           Linear.V3              (V3 (..))
 import           Network.HTTP.Simple    (getResponseBody, httpLBS)
+#if !MIN_VERSION_base(4,13,0)
+import           Control.Monad.Fail     (MonadFail(..))
+import           Prelude                hiding (fail)
+#endif
 
 -- | Decodes a 'ByteString' to 'MMTF'
 --
-decode :: Monad m => ByteString -> m MMTF
+decode :: MonadFail m => ByteString -> m MMTF
 decode = unpack
 
 -- | Fetches MMTF structure from RSCB
-fetch :: MonadIO m => String -> m MMTF
+fetch :: (MonadFail m, MonadIO m) => String -> m MMTF
 fetch pdbid = do let url = fromString $ "https://mmtf.rcsb.org/v1.0/full/" <> pdbid
                  resp <- httpLBS url
                  decode (getResponseBody resp)
diff --git a/src/Bio/MMTF/Decode.hs b/src/Bio/MMTF/Decode.hs
--- a/src/Bio/MMTF/Decode.hs
+++ b/src/Bio/MMTF/Decode.hs
@@ -14,19 +14,19 @@
 
 -- | Parses format data from ObjectMap
 --
-formatData :: Monad m => Map Text Object -> m FormatData
+formatData :: MonadFail m => Map Text Object -> m FormatData
 formatData mp = do v <- atP mp "mmtfVersion"  asStr
                    p <- atP mp "mmtfProducer" asStr
                    pure $ FormatData v p
 
 -- | Parses model data from ObjectMap
 --
-modelData :: Monad m => Map Text Object -> m ModelData
+modelData :: MonadFail m => Map Text Object -> m ModelData
 modelData mp = ModelData . l2v <$> atP mp "chainsPerModel" asIntList
 
 -- | Parses chain data from ObjectMap
 --
-chainData :: Monad m => Map Text Object -> m ChainData
+chainData :: MonadFail m => Map Text Object -> m ChainData
 chainData mp = do gpc <- atP mp "groupsPerChain" asIntList
                   cil <- codec5 . parseBinary <$> atP   mp "chainIdList"   asBinary
                   cnl <- codec5 . parseBinary <$> atPMD mp "chainNameList" asBinary empty
@@ -34,7 +34,7 @@
 
 -- | Parses atom data from ObjectMap
 --
-atomData :: Monad m => Map Text Object -> m AtomData
+atomData :: MonadFail m => Map Text Object -> m AtomData
 atomData mp = do ail' <-       codec8 . parseBinary <$> atPMD mp "atomIdList"    asBinary empty
                  all' <- c2s . codec6 . parseBinary <$> atPMD mp "altLocList"    asBinary empty
                  bfl' <-      codec10 . parseBinary <$> atPMD mp "bFactorList"   asBinary empty
@@ -46,7 +46,7 @@
 
 -- | Parses group data from ObjectMap
 --
-groupData :: Monad m => Map Text Object -> m GroupData
+groupData :: MonadFail m => Map Text Object -> m GroupData
 groupData mp = do gl' <-                                        atP   mp "groupList"          asObjectList >>= traverse (transformObjectMap >=> groupType)
                   gtl' <-              codec4 . parseBinary <$> atP   mp "groupTypeList"     asBinary
                   gil' <-              codec8 . parseBinary <$> atP   mp "groupIdList"       asBinary
@@ -57,7 +57,7 @@
 
 -- | Parses group type from ObjectMap
 --
-groupType :: Monad m => Map Text Object -> m GroupType
+groupType :: MonadFail m => Map Text Object -> m GroupType
 groupType mp = do fcl' <-          atP mp "formalChargeList" asIntList
                   anl' <-          atP mp "atomNameList"     asStrList
                   el'  <-          atP mp "elementList"      asStrList
@@ -70,7 +70,7 @@
 
 -- | Parses structure data from ObjectMap
 --
-structureData :: Monad m => Map Text Object -> m StructureData
+structureData :: MonadFail m => Map Text Object -> m StructureData
 structureData mp = do ttl' <-                                  atPMD mp "title"               asStr        ""
                       sid' <-                                  atPMD mp "structureId"         asStr        ""
                       dd'  <-                                  atPMD mp "depositionDate"      asStr        ""
@@ -98,21 +98,21 @@
 
 -- | Parses bio assembly data from ObjectMap
 --
-bioAssembly :: Monad m => Map Text Object -> m Assembly
+bioAssembly :: MonadFail m => Map Text Object -> m Assembly
 bioAssembly mp = do nme' <- atP mp "name"          asStr
                     tlt' <- atP mp "transformList" asObjectList >>= traverse (transformObjectMap >=> transform)
                     pure $ Assembly (l2v tlt') nme'
 
 -- | Parses transform data from ObjectMap
 --
-transform :: Monad m => Map Text Object -> m Transform
+transform :: MonadFail m => Map Text Object -> m Transform
 transform mp = do cil' <- atP mp "chainIndexList" asIntList
                   mtx' <- atP mp "matrix"         asFloatList >>= m44Dec
                   pure $ Transform (l2v cil') mtx'
 
 -- | Parses entity data from ObjectMap
 --
-entity :: Monad m => Map Text Object -> m Entity
+entity :: MonadFail m => Map Text Object -> m Entity
 entity mp = do cil' <- atP mp "chainIndexList" asIntList
                dsc' <- atP mp "description"    asStr
                tpe' <- atP mp "type"           asStr
diff --git a/src/Bio/MMTF/Decode/Codec.hs b/src/Bio/MMTF/Decode/Codec.hs
--- a/src/Bio/MMTF/Decode/Codec.hs
+++ b/src/Bio/MMTF/Decode/Codec.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module Bio.MMTF.Decode.Codec where
 
 import           Data.Binary          (Binary, decode)
@@ -9,6 +11,10 @@
 import           Data.Text            (Text)
 import qualified Data.Text            as T (pack)
 
+#if !MIN_VERSION_base(4,13,0)
+import Bio.MMTF.Decode.MessagePack (MonadFail)
+#endif
+
 import           Bio.MMTF.Type
 import           Bio.Structure
 
@@ -161,11 +167,11 @@
         | n == 7    = Coil
         | otherwise = Undefined
 
-ucDec :: Monad m => [Float] -> m UnitCell
+ucDec :: MonadFail m => [Float] -> m UnitCell
 ucDec [a,b,c,d,e,f] = pure $ UnitCell a b c d e f
 ucDec _             = fail "Wrong list format for unit cell"
 
-m44Dec :: Monad m => [Float] -> m M44
+m44Dec :: MonadFail m => [Float] -> m M44
 m44Dec [ a11, a12, a13, a14
        , a21, a22, a23, a24
        , a31, a32, a33, a34
diff --git a/src/Bio/MMTF/Decode/MessagePack.hs b/src/Bio/MMTF/Decode/MessagePack.hs
--- a/src/Bio/MMTF/Decode/MessagePack.hs
+++ b/src/Bio/MMTF/Decode/MessagePack.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module Bio.MMTF.Decode.MessagePack where
 
 import           Data.ByteString.Lazy  (ByteString, fromStrict)
@@ -8,14 +10,20 @@
 import           Data.Text             (Text)
 import qualified Data.Text             as T (unpack)
 
-transformObjectMap :: Monad m => Object -> m (Map Text Object)
-transformObjectMap (ObjectMap kv) = let mkPair :: Monad m => (Object, Object) -> m (Text, Object)
+#if !MIN_VERSION_base(4,13,0)
+-- Data.MessagePack includes MonadFail constraints only for GHC-8.8+, so we can't use
+-- "real" Control.Monad.Fail.MonadFail here on GHC-8.6.
+type MonadFail m = Monad m
+#endif
+
+transformObjectMap :: MonadFail m => Object -> m (Map Text Object)
+transformObjectMap (ObjectMap kv) = let mkPair :: MonadFail m => (Object, Object) -> m (Text, Object)
                                         mkPair (ObjectStr txt, v) = pure (txt, v)
                                         mkPair _ = fail "Non-string key"
                                     in  fromList <$> traverse mkPair kv
 transformObjectMap _ = fail "Wrong MessagePack MMTF format"
 
-atP :: Monad m => Map Text Object -> Text -> (Text -> Object -> m a) -> m a
+atP :: MonadFail m => Map Text Object -> Text -> (Text -> Object -> m a) -> m a
 atP m k conv =
   case M.lookup k m of
     Just x  -> conv k x
@@ -25,45 +33,45 @@
 atPM :: Monad m => Map Text Object -> Text -> (Text -> Object -> m a) -> m (Maybe a)
 atPM m k conv = traverse (conv k) $ M.lookup k m
 
-atPMD :: Monad m => Map Text Object -> Text -> (Text -> Object -> m a) -> a -> m a
+atPMD :: MonadFail m => Map Text Object -> Text -> (Text -> Object -> m a) -> a -> m a
 atPMD m k conv def = do x <- atPM m k conv
                         case x of
                           Just r  -> pure r
                           Nothing -> pure def
-                       
-asStr :: Monad m => Text -> Object -> m Text
+
+asStr :: MonadFail m => Text -> Object -> m Text
 asStr _ (ObjectStr s) = pure s
 asStr m _             = fail $ T.unpack m <> ": not a string data"
 
-asChar :: Monad m => Text -> Object -> m Char
+asChar :: MonadFail m => Text -> Object -> m Char
 asChar m = (head . T.unpack <$>) . asStr m
 
-asInt :: (Monad m, Integral a) => Text -> Object -> m a
+asInt :: (MonadFail m, Integral a) => Text -> Object -> m a
 asInt _ (ObjectInt i)  = pure (fromIntegral i)
 asInt _ (ObjectWord w) = pure (fromIntegral w)
 asInt m _              = fail $ T.unpack m <> ": not an int data"
 
-asFloat :: Monad m => Text -> Object -> m Float
+asFloat :: MonadFail m => Text -> Object -> m Float
 asFloat _ (ObjectFloat  f) = pure f
 asFloat _ (ObjectDouble f) = pure (realToFrac f)
 asFloat m _                = fail $ T.unpack m <> ": not a float data"
 
-asIntList :: (Monad m, Integral a) => Text -> Object -> m [a]
+asIntList :: (MonadFail m, Integral a) => Text -> Object -> m [a]
 asIntList m (ObjectArray l) = traverse (asInt m) l
 asIntList m _               = fail $ T.unpack m <> ": not an array of ints data"
 
-asStrList :: Monad m => Text -> Object -> m [Text]
+asStrList :: MonadFail m => Text -> Object -> m [Text]
 asStrList m (ObjectArray l) = traverse (asStr m) l
 asStrList m _               = fail $ T.unpack m <> ": not an array of string data"
 
-asFloatList :: Monad m => Text -> Object -> m [Float]
+asFloatList :: MonadFail m => Text -> Object -> m [Float]
 asFloatList m (ObjectArray l) = traverse (asFloat m) l
 asFloatList m _               = fail $ T.unpack m <> ": not an array of float data"
 
-asObjectList :: Monad m => Text -> Object -> m [Object]
+asObjectList :: MonadFail m => Text -> Object -> m [Object]
 asObjectList _ (ObjectArray l) = pure l
 asObjectList m _               = fail $ T.unpack m <> ": not an array data"
 
-asBinary :: Monad m => Text -> Object -> m ByteString
+asBinary :: MonadFail m => Text -> Object -> m ByteString
 asBinary _ (ObjectBin bs) = pure (fromStrict bs)
 asBinary m _              = fail $ T.unpack m <> ": not a binary data"
diff --git a/src/Bio/Uniprot.hs b/src/Bio/Uniprot.hs
--- a/src/Bio/Uniprot.hs
+++ b/src/Bio/Uniprot.hs
@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module Bio.Uniprot
   ( module T
   , parseRecord
@@ -9,12 +11,16 @@
 import           Data.Attoparsec.Text   ( parseOnly )
 import           Control.Monad.IO.Class ( MonadIO )
 import           Network.HTTP.Simple    ( httpBS, getResponseBody )
+#if !MIN_VERSION_base(4,13,0)
+import           Control.Monad.Fail     ( MonadFail(..) )
+import           Prelude                hiding ( fail )
+#endif
 
 import           Bio.Uniprot.Type       as T
 import           Bio.Uniprot.Parser
 
 -- | Fetches Uniprot record from Uniprot
-fetch :: MonadIO m => String -> m Record
+fetch :: (MonadFail m, MonadIO m) => String -> m Record
 fetch recid = do let url = fromString $ "https://www.uniprot.org/uniprot/" <> recid <> ".txt"
                  resp <- httpBS url
                  case parseOnly parseRecord (decodeUtf8 $ getResponseBody resp) of