diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,14 @@
+## persistent-migration 0.2.0
+
+Breaking changes:
+* Moved some types out of `Database.Persist.Migration.Operation` and into `Database.Persist.Migration.Core`
+
+Fixes:
+* Fix for GHC 8.8
+
+Other changes:
+* Re-export `rawSql` in `Database.Persist.Migration`
+
 ## persistent-migration 0.1.0
 
 Breaking changes:
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -1,10 +1,13 @@
 # persistent-migration
 
 [![CircleCI](https://circleci.com/gh/brandonchinn178/persistent-migration/tree/master.svg?style=svg)](https://circleci.com/gh/brandonchinn178/persistent-migration/tree/master)
+[![Hackage](https://img.shields.io/hackage/v/persistent-migration.svg)](https://hackage.haskell.org/package/persistent-migration)
 
 This is a migration library for the
 [persistent](http://www.stackage.org/package/persistent) package.
 
+## Overview
+
 By default, persistent provides a way to do automatic migrations; how to
 quickly and conveniently update the schema to match the definitions of the
 models. Because of its automatic nature, it will also balk at any operations
@@ -24,9 +27,10 @@
 run the `Operations` necessary to get from the current version to the latest
 version.
 
-```
+## Usage
+
+```haskell
 import Database.Persist.Migration
-import Database.Persist.Sql (PersistValue(..), rawSql)
 
 createPerson :: CreateTable
 createPerson = CreateTable
@@ -85,7 +89,7 @@
   ]
 ```
 
-```
+```haskell
 import Database.Persist.Migration (checkMigration, defaultSettings)
 import Database.Persist.Migration.Postgres (runMigration)
 
@@ -104,3 +108,22 @@
 ```
 
 For more examples, see `test/integration/Migration.hs`.
+
+## FAQs
+
+* I don't know the `SqlType` corresponding to my column's Haskell type
+
+As a general rule, complicated JSON serialization will be `SqlBlob`, but
+it might be `SqlString` for simpler data types. You can always choose one,
+and see if Persistent complains about it needing to be another type.
+
+For example, you might want to put `SqlBlob` first, and see if Persistent
+errors with something like:
+
+```
+More migrations detected:
+ * ALTER TABLE table ALTER COLUMN col TYPE VARCHAR
+```
+
+If Persistent tries to change the type to `VARCHAR`, then it probably
+wants `SqlString` instead.
diff --git a/persistent-migration.cabal b/persistent-migration.cabal
--- a/persistent-migration.cabal
+++ b/persistent-migration.cabal
@@ -1,11 +1,13 @@
--- This file has been generated from package.yaml by hpack version 0.28.2.
+cabal-version: 1.18
+
+-- This file has been generated from package.yaml by hpack version 0.33.0.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 809c91fc705a1d5507bcc49baa3cd4b3d0afd5c49c9b783cef1f88e649cd4073
+-- hash: ba05ddb62204797a742d3b09fe26c8f9469e7c342a690d1e19a803873653c5f9
 
 name:           persistent-migration
-version:        0.1.0
+version:        0.2.0
 synopsis:       Manual migrations for the persistent library
 description:    Manual migrations for the persistent library.
 category:       Database
@@ -16,7 +18,6 @@
 license:        BSD3
 license-file:   LICENSE
 build-type:     Simple
-cabal-version:  >= 1.18
 extra-doc-files:
     CHANGELOG.md
     README.md
@@ -25,11 +26,6 @@
   type: git
   location: https://github.com/brandonchinn178/persistent-migration
 
-flag dev
-  description: Turn on development settings.
-  manual: True
-  default: False
-
 library
   exposed-modules:
       Database.Persist.Migration
@@ -55,10 +51,10 @@
     , text
     , time
     , unordered-containers
-  if flag(dev)
-    ghc-options: -Werror
   if impl(ghc >= 8.0)
-    ghc-options: -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wnoncanonical-monad-instances -Wnoncanonical-monadfail-instances
+    ghc-options: -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wnoncanonical-monad-instances
+  if impl(ghc < 8.8)
+    ghc-options: -Wnoncanonical-monadfail-instances
   default-language: Haskell2010
 
 test-suite persistent-migration-integration
@@ -96,10 +92,10 @@
     , text
     , time
     , yaml
-  if flag(dev)
-    ghc-options: -Werror
   if impl(ghc >= 8.0)
-    ghc-options: -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wnoncanonical-monad-instances -Wnoncanonical-monadfail-instances
+    ghc-options: -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wnoncanonical-monad-instances
+  if impl(ghc < 8.8)
+    ghc-options: -Wnoncanonical-monadfail-instances
   default-language: Haskell2010
 
 test-suite persistent-migration-test
@@ -130,8 +126,8 @@
     , tasty-quickcheck
     , text
     , time
-  if flag(dev)
-    ghc-options: -Werror
   if impl(ghc >= 8.0)
-    ghc-options: -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wnoncanonical-monad-instances -Wnoncanonical-monadfail-instances
+    ghc-options: -Wcompat -Wincomplete-record-updates -Wincomplete-uni-patterns -Wnoncanonical-monad-instances
+  if impl(ghc < 8.8)
+    ghc-options: -Wnoncanonical-monadfail-instances
   default-language: Haskell2010
diff --git a/src/Database/Persist/Migration.hs b/src/Database/Persist/Migration.hs
--- a/src/Database/Persist/Migration.hs
+++ b/src/Database/Persist/Migration.hs
@@ -18,17 +18,18 @@
   , module Database.Persist.Migration.Utils.Sql
   , PersistValue(..)
   , SqlType(..)
+  , rawSql
   ) where
 
 import Control.Monad (unless)
 import Control.Monad.IO.Class (MonadIO)
 import qualified Data.Text as Text
-import Database.Persist (PersistValue(..), SqlType(..))
 import Database.Persist.Migration.Backend
 import Database.Persist.Migration.Core hiding (getMigration, runMigration)
 import Database.Persist.Migration.Operation
 import Database.Persist.Migration.Operation.Types
 import Database.Persist.Migration.Utils.Sql
+import Database.Persist.Sql (PersistValue(..), SqlType(..), rawSql)
 import qualified Database.Persist.Sql as Persistent
 
 -- | True if the persistent library detects more migrations unaccounted for.
@@ -39,7 +40,7 @@
 checkMigration :: MonadIO m => Persistent.Migration -> Persistent.SqlPersistT m ()
 checkMigration migration = do
   migrationText <- Persistent.showMigration migration
-  unless (null migrationText) $ fail $
+  unless (null migrationText) $ error $
     unlines $ "More migrations detected:" : bullets migrationText
   where
     bullets = map ((" * " ++ ) . Text.unpack)
diff --git a/src/Database/Persist/Migration/Core.hs b/src/Database/Persist/Migration/Core.hs
--- a/src/Database/Persist/Migration/Core.hs
+++ b/src/Database/Persist/Migration/Core.hs
@@ -10,14 +10,19 @@
 {-# LANGUAGE ExistentialQuantification #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE LambdaCase #-}
-{-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# OPTIONS_GHC -fno-warn-redundant-constraints #-}
 
 module Database.Persist.Migration.Core
-  ( MigrateSettings(..)
+  ( Version
+  , OperationPath
+  , (~>)
+  , Migration
+  , MigrationPath(..)
+  , opPath
+  , MigrateSettings(..)
   , defaultSettings
   , validateMigration
   , runMigration
@@ -32,14 +37,7 @@
 import qualified Data.Text as Text
 import Data.Time.Clock (getCurrentTime)
 import Database.Persist.Migration.Backend (MigrateBackend(..))
-import Database.Persist.Migration.Operation
-    ( Migration
-    , MigrationPath(..)
-    , Operation(..)
-    , Version
-    , opPath
-    , validateOperation
-    )
+import Database.Persist.Migration.Operation (Operation(..), validateOperation)
 import Database.Persist.Migration.Operation.Types
     (Column(..), ColumnProp(..), TableConstraint(..))
 import Database.Persist.Migration.Utils.Plan (getPath)
@@ -48,6 +46,34 @@
     (PersistValue(..), Single(..), SqlPersistT, rawExecute, rawSql)
 import Database.Persist.Types (SqlType(..))
 
+-- | The version of a database. An operation migrates from the given version to another version.
+--
+-- The version must be increasing, such that the lowest version is the first version and the highest
+-- version is the most up-to-date version.
+--
+-- A version represents a version of the database schema. In other words, any set of operations
+-- taken to get to version X *MUST* all result in the same database schema.
+type Version = Int
+
+-- | The path that an operation takes.
+type OperationPath = (Version, Version)
+
+-- | An infix constructor for 'OperationPath'.
+(~>) :: Version -> Version -> OperationPath
+(~>) = (,)
+
+-- | A migration list that defines operations to manually migrate a database schema.
+type Migration = [MigrationPath]
+
+-- | A path representing the operations needed to run to get from one version of the database schema
+-- to the next.
+data MigrationPath = OperationPath := [Operation]
+  deriving (Show)
+
+-- | Get the OperationPath in the MigrationPath.
+opPath :: MigrationPath -> OperationPath
+opPath (path := _) = path
+
 -- | Get the current version of the database, or Nothing if none exists.
 getCurrVersion :: MonadIO m => MigrateBackend -> SqlPersistT m (Maybe Version)
 getCurrVersion backend = do
@@ -136,12 +162,12 @@
   -> Migration
   -> SqlPersistT m [MigrateSql]
 getMigration backend _ migration = do
-  either fail return $ validateMigration migration
+  either error return $ validateMigration migration
   currVersion <- getCurrVersion backend
   operations <- either badPath return $ getOperations migration currVersion
-  either fail return $ mapM_ validateOperation operations
+  either error return $ mapM_ validateOperation operations
   concatMapM (mapReaderT liftIO . getMigrationSql backend) operations
   where
-    badPath (start, end) = fail $ "Could not find path: " ++ show start ++ " ~> " ++ show end
+    badPath (start, end) = error $ "Could not find path: " ++ show start ++ " ~> " ++ show end
     -- Utilities
     concatMapM f = fmap concat . mapM f
diff --git a/src/Database/Persist/Migration/Operation.hs b/src/Database/Persist/Migration/Operation.hs
--- a/src/Database/Persist/Migration/Operation.hs
+++ b/src/Database/Persist/Migration/Operation.hs
@@ -8,17 +8,10 @@
 -}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE RecordWildCards #-}
-{-# LANGUAGE TypeSynonymInstances #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
 module Database.Persist.Migration.Operation
-  ( Version
-  , OperationPath
-  , (~>)
-  , Migration
-  , MigrationPath(..)
-  , opPath
-  , Operation(..)
+  ( Operation(..)
   , validateOperation
   ) where
 
@@ -30,34 +23,6 @@
 import Database.Persist.Migration.Utils.Data (isConstr)
 import Database.Persist.Migration.Utils.Sql (MigrateSql)
 import Database.Persist.Sql (PersistValue, SqlPersistT)
-
--- | The version of a database. An operation migrates from the given version to another version.
---
--- The version must be increasing, such that the lowest version is the first version and the highest
--- version is the most up-to-date version.
---
--- A version represents a version of the database schema. In other words, any set of operations
--- taken to get to version X *MUST* all result in the same database schema.
-type Version = Int
-
--- | The path that an operation takes.
-type OperationPath = (Version, Version)
-
--- | An infix constructor for 'OperationPath'.
-(~>) :: Version -> Version -> OperationPath
-(~>) = (,)
-
--- | A migration list that defines operations to manually migrate a database schema.
-type Migration = [MigrationPath]
-
--- | A path representing the operations needed to run to get from one version of the database schema
--- to the next.
-data MigrationPath = OperationPath := [Operation]
-  deriving (Show)
-
--- | Get the OperationPath in the MigrationPath.
-opPath :: MigrationPath -> OperationPath
-opPath (path := _) = path
 
 -- | An operation that can be migrated.
 data Operation
diff --git a/src/Database/Persist/Migration/Postgres.hs b/src/Database/Persist/Migration/Postgres.hs
--- a/src/Database/Persist/Migration/Postgres.hs
+++ b/src/Database/Persist/Migration/Postgres.hs
@@ -22,7 +22,7 @@
 import qualified Data.Text as Text
 import Database.Persist.Migration
 import qualified Database.Persist.Migration.Core as Migration
-import Database.Persist.Sql (PersistValue, SqlPersistT, SqlType(..))
+import Database.Persist.Sql (SqlPersistT)
 
 -- | Run a migration with the Postgres backend.
 runMigration :: MigrateSettings -> Migration -> SqlPersistT IO ()
diff --git a/src/Database/Persist/Migration/Utils/Sql.hs b/src/Database/Persist/Migration/Utils/Sql.hs
--- a/src/Database/Persist/Migration/Utils/Sql.hs
+++ b/src/Database/Persist/Migration/Utils/Sql.hs
@@ -6,6 +6,7 @@
 
 Defines helper functions for writing SQL queries.
 -}
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
 
@@ -22,7 +23,9 @@
   ) where
 
 import Control.Monad.IO.Class (MonadIO(..))
+#if !MIN_VERSION_base(4,11,0)
 import Data.Monoid ((<>))
+#endif
 import Data.Text (Text)
 import qualified Data.Text as Text
 import Database.Persist.Sql (PersistValue(..), SqlPersistT)
diff --git a/test/integration/Migration.hs b/test/integration/Migration.hs
--- a/test/integration/Migration.hs
+++ b/test/integration/Migration.hs
@@ -1,4 +1,6 @@
 {-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE DerivingStrategies #-}
 {-# LANGUAGE ExistentialQuantification #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
@@ -8,8 +10,10 @@
 {-# LANGUAGE QuasiQuotes #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE StandaloneDeriving #-}
 {-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE UndecidableInstances #-}
 {-# OPTIONS_GHC -fno-warn-unused-top-binds #-}
 
 module Migration (testMigrations) where
@@ -18,22 +22,15 @@
 import Control.Monad (unless, when)
 import Data.ByteString.Lazy (ByteString, fromStrict)
 import Data.Maybe (mapMaybe)
+#if !MIN_VERSION_base(4,11,0)
 import Data.Monoid ((<>))
+#endif
 import Data.Pool (Pool)
 import Data.Text (Text)
 import Data.Yaml (array, encode, object, (.=))
 import Database.Persist (Entity(..), get, insertKey, insertMany_, selectList)
 import Database.Persist.Migration
-import Database.Persist.Migration.Utils.Sql (uncommas, uncommas')
-import Database.Persist.Sql
-    ( PersistValue(..)
-    , Single(..)
-    , SqlBackend
-    , SqlPersistT
-    , SqlType(..)
-    , rawExecute
-    , rawSql
-    )
+import Database.Persist.Sql (Single(..), SqlBackend, SqlPersistT, rawExecute)
 import Database.Persist.TH
     (mkMigrate, mkPersist, persistLowerCase, share, sqlSettings)
 import Test.Tasty (TestTree, testGroup)
diff --git a/test/integration/Property.hs b/test/integration/Property.hs
--- a/test/integration/Property.hs
+++ b/test/integration/Property.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE DuplicateRecordFields #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE LambdaCase #-}
@@ -11,7 +12,9 @@
 import Control.Monad.IO.Class (liftIO)
 import Data.List (nub)
 import Data.Maybe (mapMaybe)
+#if !MIN_VERSION_base(4,11,0)
 import Data.Monoid ((<>))
+#endif
 import Data.Pool (Pool)
 import qualified Data.Text as Text
 import qualified Data.Text.IO as Text
@@ -123,9 +126,9 @@
       table <- pick arbitrary
       fkTables <- pick $ getForeignKeyTables table
       runSqlPool' $ mapM_ (runOperation' . toOperation) (fkTables ++ [table])
-      isSuccess <- toBool <$> action (table, fkTables)
+      isSuccessful <- toBool <$> action (table, fkTables)
       runSqlPool' $ mapM_ dropTable' (table:fkTables)
-      unless isSuccess $ stop rejected
+      unless isSuccessful $ stop rejected
     dropTable' CreateTable'{ctName} = runOperation' $ DropTable ctName
 
 {- Helpers -}
diff --git a/test/integration/Utils/Backends.hs b/test/integration/Utils/Backends.hs
--- a/test/integration/Utils/Backends.hs
+++ b/test/integration/Utils/Backends.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE OverloadedStrings #-}
 
 module Utils.Backends
@@ -7,7 +8,9 @@
 import Control.Concurrent (threadDelay)
 import Control.Monad.Logger (runNoLoggingT)
 import qualified Data.ByteString.Char8 as ByteString
+#if !MIN_VERSION_base(4,11,0)
 import Data.Monoid ((<>))
+#endif
 import Data.Pool (Pool, destroyAllResources)
 import qualified Data.Text as Text
 import qualified Data.Text.IO as Text
diff --git a/test/unit/Migration.hs b/test/unit/Migration.hs
--- a/test/unit/Migration.hs
+++ b/test/unit/Migration.hs
@@ -7,7 +7,6 @@
 import qualified Data.Text as Text
 import Database.Persist.Migration
 import Database.Persist.Migration.Core (getMigration)
-import Database.Persist.Sql (SqlType(..))
 import Test.Tasty (TestName, TestTree, testGroup)
 
 import Utils.Backends
diff --git a/test/unit/Utils/Backends.hs b/test/unit/Utils/Backends.hs
--- a/test/unit/Utils/Backends.hs
+++ b/test/unit/Utils/Backends.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
@@ -70,6 +71,9 @@
     , connLimitOffset = error "connLimitOffset"
     , connLogFunc = \_ _ _ _ -> return ()
     , connMaxParams = error "connMaxParams"
+#if MIN_VERSION_persistent(2, 9, 0)
+    , connRepsertManySql = error "connRepsertManySql"
+#endif
     }
   where
     stmt = Statement
diff --git a/test/utils/Utils/QuickCheck.hs b/test/utils/Utils/QuickCheck.hs
--- a/test/utils/Utils/QuickCheck.hs
+++ b/test/utils/Utils/QuickCheck.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
@@ -19,7 +20,9 @@
 import Data.ByteString (ByteString)
 import qualified Data.ByteString.Char8 as ByteString
 import Data.List (nub)
+#if !MIN_VERSION_base(4,11,0)
 import Data.Monoid ((<>))
+#endif
 import Data.Text (Text)
 import qualified Data.Text as Text
 import qualified Data.Text.Encoding as Text
@@ -56,7 +59,7 @@
     let tableNames' = filter (/= name) tableNames
     cols <- vectorOf (length colNames') $ genColumn tableNames'
     let idCol = Column "id" SqlInt32 [NotNull, AutoIncrement]
-        cols' = map (\(colName', col) -> col{colName = colName'}) $ zip colNames' cols
+        cols' = zipWith (\colName' col -> col{colName = colName'}) colNames' cols
         ctSchema = idCol : cols'
 
     -- all of the columns that will be unique
@@ -171,7 +174,7 @@
   SqlTime -> PersistTimeOfDay <$> arbitrary
   SqlDayTime -> PersistUTCTime <$> arbitrary
   SqlBlob -> PersistByteString . ByteString.map cleanText <$> arbitrary
-  SqlOther _ -> fail "SqlOther not supported"
+  SqlOther _ -> error "SqlOther not supported"
   where
     cleanDouble :: Double -> Double
     cleanDouble x = if isInfinite x || isNaN x then 0 else x