diff --git a/Cabal-described/src/Distribution/Utils/CharSet.hs b/Cabal-described/src/Distribution/Utils/CharSet.hs
index 45bfbb1300b..3cb9ba500a8 100644
--- a/Cabal-described/src/Distribution/Utils/CharSet.hs
+++ b/Cabal-described/src/Distribution/Utils/CharSet.hs
@@ -240,3 +240,8 @@ alphanum = foldl' (flip insert) empty [ c | c <- [ minBound .. maxBound ], isAlp
 upper :: CharSet
 upper = foldl' (flip insert) empty [ c | c <- [ minBound .. maxBound ], isUpper c ]
 {-# NOINLINE upper #-}
+
+-- $setup
+-- Use -XOverloadedStrings to avoid the error: Couldn't match type ‘[Char]’ with ‘CharSet’
+-- >>> :set -XOverloadedStrings
+-- >>> import Prelude (length)
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 9718bfd696c..b37298f2aee 100644
--- a/Makefile
+++ b/Makefile
@@ -3,6 +3,7 @@
 
 CABALBUILD := cabal build
 CABALRUN   := cabal run
+DOCTEST    := cabal repl --with-ghc=doctest --repl-options="-w" --project-file=cabal.project.doctest
 
 # default rules
 
@@ -85,9 +86,10 @@ ghcid-cli :
 #       https://github.com/haskell/cabal/issues/8734
 #       Just as well, cabal-install(-solver) doctests (the target below) bitrotted and need some care.
 doctest :
-	cabal repl --with-ghc=doctest --build-depends=QuickCheck --build-depends=template-haskell --repl-options="-w" --project-file="cabal.project.doctest" Cabal-syntax
-	cabal repl --with-ghc=doctest --build-depends=QuickCheck --build-depends=template-haskell --repl-options="-w" --project-file="cabal.project.doctest" Cabal
-
+	$(DOCTEST) Cabal-syntax
+	$(DOCTEST) Cabal-described
+	$(DOCTEST) --build-depends=QuickCheck Cabal
+	$(DOCTEST) cabal-install
 
 # This is not run as part of validate.sh (we need hackage-security, which is tricky to get).
 doctest-cli :
diff --git a/cabal-install/src/Distribution/Client/IndexUtils/ActiveRepos.hs b/cabal-install/src/Distribution/Client/IndexUtils/ActiveRepos.hs
index e65000e6b98..daa4ec86355 100644
--- a/cabal-install/src/Distribution/Client/IndexUtils/ActiveRepos.hs
+++ b/cabal-install/src/Distribution/Client/IndexUtils/ActiveRepos.hs
@@ -70,7 +70,7 @@ instance Pretty ActiveRepos where
 -- Just (ActiveRepos [ActiveRepoRest CombineStrategyMerge])
 --
 -- >>> simpleParsec "hackage.haskell.org, :rest, head.hackage:override" :: Maybe ActiveRepos
--- Just (ActiveRepos [ActiveRepo (RepoName "hackage.haskell.org") CombineStrategyMerge,ActiveRepoRest CombineStrategyMerge,ActiveRepo (RepoName "head.hackage") CombineStrategyOverride])
+-- Just (ActiveRepos [ActiveRepo (RepoName {unRepoName = "hackage.haskell.org"}) CombineStrategyMerge,ActiveRepoRest CombineStrategyMerge,ActiveRepo (RepoName {unRepoName = "head.hackage"}) CombineStrategyOverride])
 instance Parsec ActiveRepos where
   parsec =
     ActiveRepos [] <$ P.try (P.string ":none")
@@ -148,13 +148,13 @@ instance Parsec CombineStrategy where
 --
 -- >>> let repos = [RepoName "a", RepoName "b", RepoName "c"]
 -- >>> organizeByRepos (ActiveRepos [ActiveRepoRest CombineStrategyMerge]) id repos
--- Right [(RepoName "a",CombineStrategyMerge),(RepoName "b",CombineStrategyMerge),(RepoName "c",CombineStrategyMerge)]
+-- Right [(RepoName {unRepoName = "a"},CombineStrategyMerge),(RepoName {unRepoName = "b"},CombineStrategyMerge),(RepoName {unRepoName = "c"},CombineStrategyMerge)]
 --
 -- >>> organizeByRepos (ActiveRepos [ActiveRepo (RepoName "b") CombineStrategyOverride, ActiveRepoRest CombineStrategyMerge]) id repos
--- Right [(RepoName "b",CombineStrategyOverride),(RepoName "a",CombineStrategyMerge),(RepoName "c",CombineStrategyMerge)]
+-- Right [(RepoName {unRepoName = "b"},CombineStrategyOverride),(RepoName {unRepoName = "a"},CombineStrategyMerge),(RepoName {unRepoName = "c"},CombineStrategyMerge)]
 --
 -- >>> organizeByRepos (ActiveRepos [ActiveRepoRest CombineStrategyMerge, ActiveRepo (RepoName "b") CombineStrategyOverride]) id repos
--- Right [(RepoName "a",CombineStrategyMerge),(RepoName "c",CombineStrategyMerge),(RepoName "b",CombineStrategyOverride)]
+-- Right [(RepoName {unRepoName = "a"},CombineStrategyMerge),(RepoName {unRepoName = "c"},CombineStrategyMerge),(RepoName {unRepoName = "b"},CombineStrategyOverride)]
 --
 -- >>> organizeByRepos (ActiveRepos [ActiveRepoRest CombineStrategyMerge, ActiveRepo (RepoName "d") CombineStrategyOverride]) id repos
 -- Left "no repository provided d"
diff --git a/cabal-install/src/Distribution/Client/IndexUtils/IndexState.hs b/cabal-install/src/Distribution/Client/IndexUtils/IndexState.hs
index 8acf2b3bdc3..0e9cb6a73d3 100644
--- a/cabal-install/src/Distribution/Client/IndexUtils/IndexState.hs
+++ b/cabal-install/src/Distribution/Client/IndexUtils/IndexState.hs
@@ -68,10 +68,10 @@ instance Pretty TotalIndexState where
 -- Just (TIS IndexStateHead (fromList []))
 --
 -- >>> simpleParsec "2020-02-04T12:34:56Z, hackage.haskell.org HEAD" :: Maybe TotalIndexState
--- Just (TIS (IndexStateTime (TS 1580819696)) (fromList [(RepoName "hackage.haskell.org",IndexStateHead)]))
+-- Just (TIS (IndexStateTime (TS 1580819696)) (fromList [(RepoName {unRepoName = "hackage.haskell.org"},IndexStateHead)]))
 --
 -- >>> simpleParsec "hackage.haskell.org 2020-02-04T12:34:56Z" :: Maybe TotalIndexState
--- Just (TIS IndexStateHead (fromList [(RepoName "hackage.haskell.org",IndexStateTime (TS 1580819696))]))
+-- Just (TIS IndexStateHead (fromList [(RepoName {unRepoName = "hackage.haskell.org"},IndexStateTime (TS 1580819696))]))
 instance Parsec TotalIndexState where
   parsec = normalise . foldl' add headTotalIndexState <$> parsecLeadingCommaNonEmpty single0
     where
diff --git a/cabal-install/src/Distribution/Client/Types/RepoName.hs b/cabal-install/src/Distribution/Client/Types/RepoName.hs
index 2eb2fb15fc8..1a9b8012aa9 100644
--- a/cabal-install/src/Distribution/Client/Types/RepoName.hs
+++ b/cabal-install/src/Distribution/Client/Types/RepoName.hs
@@ -29,7 +29,7 @@ instance Pretty RepoName where
 -- |
 --
 -- >>> simpleParsec "hackage.haskell.org" :: Maybe RepoName
--- Just (RepoName "hackage.haskell.org")
+-- Just (RepoName {unRepoName = "hackage.haskell.org"})
 --
 -- >>> simpleParsec "0123" :: Maybe RepoName
 -- Nothing