diff --git a/Application.hs b/Application.hs
index 214003d..a526580 100644
--- a/Application.hs
+++ b/Application.hs
@@ -9,12 +9,8 @@ module Application
 import qualified Aws
 import           Control.Concurrent (forkIO, threadDelay)
 import           Control.Exception (catch)
-import           Control.Monad.Logger (runLoggingT, LoggingT, runStdoutLoggingT, defaultLogStr, LogLevel (LevelDebug))
-import           Control.Monad.Reader (MonadReader (..))
-import           Control.Monad.Reader (runReaderT, ReaderT)
-import           Control.Monad.Trans.Control
+import           Control.Monad.Logger (runLoggingT, LoggingT, defaultLogStr)
 import           Data.BlobStore (fileStore, storeWrite, cachedS3Store)
-import           Data.Conduit.Lazy (MonadActive, monadActive)
 import           Data.Hackage
 import           Data.Hackage.Views
 import           Data.Time (diffUTCTime)
diff --git a/Data/BlobStore.hs b/Data/BlobStore.hs
index 2a6f71c..65ee779 100644
--- a/Data/BlobStore.hs
+++ b/Data/BlobStore.hs
@@ -11,9 +11,7 @@ module Data.BlobStore
     ) where
 
 import ClassyPrelude.Yesod
-import Control.Exception.Lifted (bracketOnError)
 import qualified Filesystem as F
-import Control.Monad.Reader (MonadReader, ask)
 import Control.Monad.Trans.Resource (release)
 import qualified Aws
 import Aws.S3 as Aws
diff --git a/Data/Hackage.hs b/Data/Hackage.hs
index 3c91fb3..2082f88 100644
--- a/Data/Hackage.hs
+++ b/Data/Hackage.hs
@@ -14,13 +14,11 @@ import Types
 import Data.BlobStore
 import Data.Conduit.Lazy (MonadActive (..), lazyConsume)
 import qualified Codec.Archive.Tar as Tar
-import Control.Monad.Reader (MonadReader, ask, runReaderT)
 import Control.Monad.Logger (runNoLoggingT)
 import qualified Data.Text as T
 import Data.Conduit.Zlib (ungzip, gzip)
 import System.IO.Temp (withSystemTempFile, withSystemTempDirectory)
 import System.IO (IOMode (ReadMode), openBinaryFile)
-import Control.Monad.Catch (MonadMask)
 import Model (Uploaded (Uploaded), Metadata (..))
 import Filesystem (createTree)
 import Distribution.PackageDescription.Parse (parsePackageDescription, ParseResult (ParseOk))
diff --git a/Data/Slug.hs b/Data/Slug.hs
index 50d8f3a..cc60ef3 100644
--- a/Data/Slug.hs
+++ b/Data/Slug.hs
@@ -13,7 +13,6 @@ module Data.Slug
 import ClassyPrelude.Yesod
 import Database.Persist.Sql (PersistFieldSql (sqlType))
 import qualified System.Random.MWC as MWC
-import Control.Monad.Reader (MonadReader, ask)
 import GHC.Prim (RealWorld)
 import Text.Blaze (ToMarkup)
 
@@ -32,9 +31,9 @@ mkSlug t
   where
 
 mkSlugLen :: MonadThrow m => Int -> Int -> Text -> m Slug
-mkSlugLen minLen maxLen t
-    | length t < minLen = throwM $ InvalidSlugException t "Too short"
-    | length t > maxLen = throwM $ InvalidSlugException t "Too long"
+mkSlugLen minLen' maxLen' t
+    | length t < minLen' = throwM $ InvalidSlugException t "Too short"
+    | length t > maxLen' = throwM $ InvalidSlugException t "Too long"
     | any (not . validChar) t = throwM $ InvalidSlugException t "Contains invalid characters"
     | "-" `isPrefixOf` t = throwM $ InvalidSlugException t "Must not start with a hyphen"
     | otherwise = return $ Slug t
diff --git a/Foundation.hs b/Foundation.hs
index 9a73f08..65ea1fe 100644
--- a/Foundation.hs
+++ b/Foundation.hs
@@ -112,7 +112,7 @@ instance Yesod App where
         mcurr <- getCurrentRoute
         let notHome = mcurr /= Just HomeR
 
-        giveUrlRenderer $(hamletFile "templates/default-layout-wrapper.hamlet")
+        withUrlRenderer $(hamletFile "templates/default-layout-wrapper.hamlet")
 
     -- This is done to provide an optimization for serving static files from
     -- a separate domain. Please see the staticRoot setting in Settings.hs
diff --git a/Handler/Package.hs b/Handler/Package.hs
index 73dffb4..31e5469 100644
--- a/Handler/Package.hs
+++ b/Handler/Package.hs
@@ -20,8 +20,6 @@ import           Text.Email.Validate
 getPackageR :: PackageName -> Handler Html
 getPackageR pn = do
     let maxSnaps = 10
-        asInt :: Int -> Int
-        asInt = id
         haddocksLink ident version =
             HaddockR ident [concat [toPathPiece pn, "-", toPathPiece version]]
     muid <- maybeAuthId
@@ -38,8 +36,8 @@ getPackageR pn = do
         let getLiked uid = (>0) <$> count [LikePackage ==. pn, LikeVoter ==. uid]
         liked <- maybe (return False) getLiked muid
         downloads <- count [DownloadPackage ==. pn]
-        now <- liftIO getCurrentTime
-        let nowMinus30 = addUTCTime (-30 * 24 * 60 * 60) now
+        now' <- liftIO getCurrentTime
+        let nowMinus30 = addUTCTime (-30 * 24 * 60 * 60) now'
         recentDownloads <- count [DownloadPackage ==. pn, DownloadTimestamp >=. nowMinus30]
         metadata <- getBy404 (UniqueMetadata pn)
 
diff --git a/Handler/Snapshots.hs b/Handler/Snapshots.hs
index 4f8e710..067bc0d 100644
--- a/Handler/Snapshots.hs
+++ b/Handler/Snapshots.hs
@@ -17,8 +17,8 @@ import           Import
 -- inclined, or create a single monolithic file.
 getAllSnapshotsR :: Handler Html
 getAllSnapshotsR = do
-    now <- liftIO getCurrentTime
-    groups <- fmap (groupBy (on (==) (\(_,_,uploaded,_,_) -> uploaded)) . map (uncrapify now)) $
+    now' <- liftIO getCurrentTime
+    groups <- fmap (groupBy (on (==) (\(_,_,uploaded,_,_) -> uploaded)) . map (uncrapify now')) $
         runDB $ E.select $ E.from $ \(stackage `E.InnerJoin` user) -> do
           E.on (stackage E.^. StackageUser E.==. user E.^. UserId)
           E.orderBy [E.desc $ stackage E.^. StackageUploaded]
@@ -32,6 +32,6 @@ getAllSnapshotsR = do
     defaultLayout $ do
         setTitle "Stackage Server"
         $(widgetFile "all-snapshots")
-  where uncrapify now c =
-            let (E.Value ident, E.Value title, E.Value uploaded, E.Value display, E.Value handle) = c
-            in (ident,title,format (diff True) (diffUTCTime uploaded now),display,handle)
+  where uncrapify now' c =
+            let (E.Value ident, E.Value title, E.Value uploaded, E.Value display, E.Value handle') = c
+            in (ident,title,format (diff True) (diffUTCTime uploaded now'),display,handle')
diff --git a/Handler/StackageIndex.hs b/Handler/StackageIndex.hs
index 0e95139..38feeda 100644
--- a/Handler/StackageIndex.hs
+++ b/Handler/StackageIndex.hs
@@ -2,7 +2,6 @@ module Handler.StackageIndex where
 
 import Import
 import Data.BlobStore
-import Network.Wai (responseBuilder)
 
 getStackageIndexR :: PackageSetIdent -> Handler TypedContent
 getStackageIndexR ident = do
diff --git a/templates/all-snapshots.hamlet b/templates/all-snapshots.hamlet
index 39d13d0..7fafd1a 100644
--- a/templates/all-snapshots.hamlet
+++ b/templates/all-snapshots.hamlet
@@ -5,7 +5,7 @@
             <h3>
                 #{uploaded}
         <ul .snapshots>
-            $forall (ident, title, uploaded, display, handle) <- stackages
+            $forall (ident, title, _uploaded, display, handle) <- stackages
                 <li>
                     <strong>
                         <a href=@{StackageHomeR ident}>