diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -1,12 +1,12 @@
 lambdabot ![Build Status](https://travis-ci.org/lambdabot/lambdabot.png)
 ===============
 
-Lambdabot is an IRC bot written over several years by those on freenode's #haskell [IRC channel](https://wiki.haskell.org/IRC_channel). It also operates in an offline mode as a Haskell development tool, and embedded as an extension to ghci.
+Lambdabot is an IRC bot written over several years by those on Libera's (formerly freenode's) #haskell [IRC channel](https://wiki.haskell.org/IRC_channel). It also operates in an offline mode as a Haskell development tool, and embedded as an extension to ghci.
 
 PREREQUISITES
 -------------
 
-You'll need GHC >= 7.4.  cabal-install is highly recommended.
+You'll need GHC >= 8.2.  cabal-install is highly recommended.
 
 External executable dependencies:
 
@@ -65,7 +65,7 @@
 
 When doing so, configuration is passed in to the `lambdabotMain` function as a list of bindings.  Configuration variables are bound using the `:=>` operator (actually the data constructor of the `DSum` type), for example:
 
-    ghcBinary :=> "ghc-7.4.2"
+    ghcBinary :=> "ghc-8.10.5"
 
 So a typical custom lambdabot executable might look something like:
 
diff --git a/lambdabot-core.cabal b/lambdabot-core.cabal
--- a/lambdabot-core.cabal
+++ b/lambdabot-core.cabal
@@ -1,11 +1,11 @@
 name:                   lambdabot-core
-version:                5.3.0.1
+version:                5.3.0.2
 
 license:                GPL
 license-file:           LICENSE
 
 author:                 Don Stewart
-maintainer:             James Cook <mokus@deepbondi.net>
+maintainer:             Bertram Felgenhauer <int-e@gmx.de>
 
 category:               Development, Web
 synopsis:               Lambdabot core functionality
@@ -19,7 +19,7 @@
 
 build-type:             Simple
 cabal-version:          >= 1.10
-tested-with:            GHC == 8.2.2, GHC == 8.4.4, GHC == 8.6.5, GHC == 8.8.3, GHC == 8.10.1
+tested-with:            GHC == 8.2.2, GHC == 8.4.4, GHC == 8.6.5, GHC == 8.8.4, GHC == 8.10.4
 
 extra-source-files:     AUTHORS.md
                         COMMENTARY.md
diff --git a/src/Lambdabot/Util/Serial.hs b/src/Lambdabot/Util/Serial.hs
--- a/src/Lambdabot/Util/Serial.hs
+++ b/src/Lambdabot/Util/Serial.hs
@@ -132,10 +132,12 @@
 
         showPacked = gzip . P.unlines . concatMap (\(k,v) -> [k,v])
 
-instance Packable (M.Map P.ByteString (Bool, [(String, Int)])) where
+-- The following instance is used by the `poll` plugin.
+-- The `read` and `show` are there for backward compatibility.
+instance Packable (M.Map P.ByteString (Bool, [(P.ByteString, Int)])) where
     readPacked = M.fromList . readKV . P.lines
         where
-          readKV :: [P.ByteString] -> [(P.ByteString,(Bool, [(String, Int)]))]
+          readKV :: [P.ByteString] -> [(P.ByteString,(Bool, [(P.ByteString, Int)]))]
           readKV []         = []
           readKV (k:v:rest) = (k, (read . P.unpack) v) : readKV rest
           readKV _          = error "Vote.readPacked: parse failed"