diff --git a/.hlint.yaml b/.hlint.yaml
new file mode 100644
--- /dev/null
+++ b/.hlint.yaml
@@ -0,0 +1,4 @@
+- arguments: [--cpp-define=HLINT, --cpp-ansi]
+
+- ignore: {name: Use fmap}
+- ignore: {name: Use lambda-case}
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
--- a/.travis.yml
+++ /dev/null
@@ -1,153 +0,0 @@
-# This Travis job script has been generated by a script via
-#
-#   runghc make_travis_yml_2.hs '-o' '.travis.yml' '--irc-channel=irc.freenode.org#haskell-lens' '--no-no-tests-no-bench' '--no-installed' 'cabal.project'
-#
-# For more information, see https://github.com/hvr/multi-ghc-travis
-#
-language: c
-sudo: false
-
-git:
-  submodules: false  # whether to recursively clone submodules
-
-notifications:
-  irc:
-    channels:
-      - "irc.freenode.org#haskell-lens"
-    skip_join: true
-    template:
-      - "\x0313zippers\x03/\x0306%{branch}\x03 \x0314%{commit}\x03 %{build_url} %{message}"
-
-cache:
-  directories:
-    - $HOME/.cabal/packages
-    - $HOME/.cabal/store
-
-before_cache:
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/build-reports.log
-  # remove files that are regenerated by 'cabal update'
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/00-index.*
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/*.json
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.cache
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.tar
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.tar.idx
-
-  - rm -rfv $HOME/.cabal/packages/head.hackage
-
-addons:
-  apt:
-    packages: &apt_packages
-      - ghc-ppa-tools
-      - hlint
-
-matrix:
-  include:
-    - compiler: "ghc-7.4.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [*apt_packages,cabal-install-2.0,ghc-7.4.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.6.3"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [*apt_packages,cabal-install-2.0,ghc-7.6.3], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.8.4"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [*apt_packages,cabal-install-2.0,ghc-7.8.4], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.10.3"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [*apt_packages,cabal-install-2.0,ghc-7.10.3], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.0.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [*apt_packages,cabal-install-2.0,ghc-8.0.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.2.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [*apt_packages,cabal-install-2.0,ghc-8.2.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.4.1"
-      env: GHCHEAD=true
-      addons: {apt: {packages: [*apt_packages,cabal-install-head,ghc-8.4.1], sources: [hvr-ghc]}}
-    - compiler: "ghc-head"
-      env: GHCHEAD=true
-      addons: {apt: {packages: [*apt_packages,cabal-install-head,ghc-head], sources: [hvr-ghc]}}
-
-  allow_failures:
-    - compiler: "ghc-8.4.1"
-    - compiler: "ghc-head"
-
-before_install:
-  - HC=${CC}
-  - HCPKG=${HC/ghc/ghc-pkg}
-  - unset CC
-  - ROOTDIR=$(pwd)
-  - mkdir -p $HOME/.local/bin
-  - "PATH=/opt/ghc/bin:/opt/ghc-ppa-tools/bin:$HOME/local/bin:$PATH"
-  - HCNUMVER=$(( $(${HC} --numeric-version|sed -E 's/([0-9]+)\.([0-9]+)\.([0-9]+).*/\1 * 10000 + \2 * 100 + \3/') ))
-  - echo $HCNUMVER
-
-install:
-  - cabal --version
-  - echo "$(${HC} --version) [$(${HC} --print-project-git-commit-id 2> /dev/null || echo '?')]"
-  - BENCH=${BENCH---enable-benchmarks}
-  - TEST=${TEST---enable-tests}
-  - HADDOCK=${HADDOCK-true}
-  - INSTALLED=${INSTALLED-true}
-  - GHCHEAD=${GHCHEAD-false}
-  - travis_retry cabal update -v
-  - "sed -i.bak 's/^jobs:/-- jobs:/' ${HOME}/.cabal/config"
-  - rm -fv cabal.project cabal.project.local
-  # Overlay Hackage Package Index for GHC HEAD: https://github.com/hvr/head.hackage
-  - |
-    if $GHCHEAD; then
-      sed -i.bak 's/-- allow-newer:.*/allow-newer: *:base, *:template-haskell, *:ghc, *:Cabal/' ${HOME}/.cabal/config
-
-      echo 'repository head.hackage'                                                        >> ${HOME}/.cabal/config
-      echo '   url: http://head.hackage.haskell.org/'                                       >> ${HOME}/.cabal/config
-      echo '   secure: True'                                                                >> ${HOME}/.cabal/config
-      echo '   root-keys: 07c59cb65787dedfaef5bd5f987ceb5f7e5ebf88b904bbd4c5cbdeb2ff71b740' >> ${HOME}/.cabal/config
-      echo '              2e8555dde16ebd8df076f1a8ef13b8f14c66bad8eafefd7d9e37d0ed711821fb' >> ${HOME}/.cabal/config
-      echo '              8f79fd2389ab2967354407ec852cbe73f2e8635793ac446d09461ffb99527f6e' >> ${HOME}/.cabal/config
-      echo '   key-threshold: 3'                                                            >> ${HOME}/.cabal.config
-
-      cabal new-update head.hackage -v
-    fi
-  - grep -Ev -- '^\s*--' ${HOME}/.cabal/config | grep -Ev '^\s*$'
-  - "printf 'packages: \".\" \"./examples\"\\n' > cabal.project"
-  - cat cabal.project
-  - if [ -f "./configure.ac" ]; then
-      (cd "." && autoreconf -i);
-    fi
-  - if [ -f "./examples/configure.ac" ]; then
-      (cd "./examples" && autoreconf -i);
-    fi
-  - rm -f cabal.project.freeze
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} --project-file="cabal.project" --dep -j2 all
-  - rm -rf "."/.ghc.environment.* "./examples"/.ghc.environment.* "."/dist "./examples"/dist
-  - DISTDIR=$(mktemp -d /tmp/dist-test.XXXX)
-
-# Here starts the actual work to be performed for the package under test;
-# any command which exits with a non-zero exit code causes the build to fail.
-script:
-  # test that source-distributions can be generated
-  - (cd "." && cabal sdist)
-  - (cd "./examples" && cabal sdist)
-  - mv "."/dist/zippers-*.tar.gz "./examples"/dist/zippers-examples-*.tar.gz ${DISTDIR}/
-  - cd ${DISTDIR} || false
-  - find . -maxdepth 1 -name '*.tar.gz' -exec tar -xvf '{}' \;
-  - "printf 'packages: zippers-*/*.cabal zippers-examples-*/*.cabal\\n' > cabal.project"
-  - cat cabal.project
-
-
-  # build & run tests, build benchmarks
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} all
-  - if [ "x$TEST" = "x--enable-tests" ]; then cabal new-test -w ${HC} ${TEST} ${BENCH} all; fi
-
-  # cabal check
-  - (cd zippers-* && cabal check)
-  - (cd zippers-examples-* && cabal check)
-
-  # haddock
-  - rm -rf ./dist-newstyle
-  - if $HADDOCK; then cabal new-haddock -w ${HC} ${TEST} ${BENCH} all; else echo "Skipping haddock generation";fi
-
-  # hlint
-  - (cd zippers-* && hlint src --cpp-define=HLINT --cpp-ansi)
-
-# REGENDATA ["-o",".travis.yml","--irc-channel=irc.freenode.org#haskell-lens","--no-no-tests-no-bench","--no-installed","cabal.project"]
-# EOF
diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,19 @@
+0.3.2 [2021.11.16]
+------------------
+* Drop support for pre-8.0 versions of GHC.
+
+0.3.1 [2021.02.18]
+------------------
+* Allow building with `lens-5.*`.
+* The build-type has been changed from `Custom` to `Simple`.
+  To achieve this, the `doctests` test suite has been removed in favor of using
+  [`cabal-docspec`](https://github.com/phadej/cabal-extras/tree/master/cabal-docspec)
+  to run the doctests.
+
+0.3 [2019.05.10]
+----------------
+* `jerks` now has a `MonadFail` constraint instead of just `Monad`.
+
 0.2.5
 -----
 * Add `Semigroup` instance for `Jacket`.
diff --git a/HLint.hs b/HLint.hs
deleted file mode 100644
--- a/HLint.hs
+++ /dev/null
@@ -1,1 +0,0 @@
-import "hint" HLint.Default
diff --git a/README.markdown b/README.markdown
--- a/README.markdown
+++ b/README.markdown
@@ -1,7 +1,7 @@
 zippers
 ===
 
-[![Hackage](https://img.shields.io/hackage/v/zippers.svg)](https://hackage.haskell.org/package/zippers) [![Build Status](https://secure.travis-ci.org/ekmett/zippers.png?branch=master)](http://travis-ci.org/ekmett/zippers)
+[![Hackage](https://img.shields.io/hackage/v/zippers.svg)](https://hackage.haskell.org/package/zippers) [![Build Status](https://github.com/ekmett/zippers/workflows/Haskell-CI/badge.svg)](https://github.com/ekmett/zippers/actions?query=workflow%3AHaskell-CI)
 
 Zippers are a way of accessing and manipulating data deep within a structure. This library uses Lenses and Traversals from the lens library to do this effectively.
 
diff --git a/Setup.lhs b/Setup.lhs
--- a/Setup.lhs
+++ b/Setup.lhs
@@ -1,34 +1,7 @@
-\begin{code}
-{-# LANGUAGE CPP #-}
-{-# OPTIONS_GHC -Wall #-}
-module Main (main) where
-
-#ifndef MIN_VERSION_cabal_doctest
-#define MIN_VERSION_cabal_doctest(x,y,z) 0
-#endif
-
-#if MIN_VERSION_cabal_doctest(1,0,0)
-
-import Distribution.Extra.Doctest ( defaultMainWithDoctests )
-main :: IO ()
-main = defaultMainWithDoctests "doctests"
-
-#else
-
-#ifdef MIN_VERSION_Cabal
--- If the macro is defined, we have new cabal-install,
--- but for some reason we don't have cabal-doctest in package-db
---
--- Probably we are running cabal sdist, when otherwise using new-build
--- workflow
-import Warning ()
-#endif
-
-import Distribution.Simple
-
-main :: IO ()
-main = defaultMain
+#!/usr/bin/runhaskell
+> module Main (main) where
 
-#endif
+> import Distribution.Simple
 
-\end{code}
+> main :: IO ()
+> main = defaultMain
diff --git a/Warning.hs b/Warning.hs
deleted file mode 100644
--- a/Warning.hs
+++ /dev/null
@@ -1,5 +0,0 @@
-module Warning
-  {-# WARNING ["You are configuring this package without cabal-doctest installed.",
-               "The doctests test-suite will not work as a result.",
-               "To fix this, install cabal-doctest before configuring."] #-}
-  () where
diff --git a/benchmarks/zipper.hs b/benchmarks/zipper.hs
--- a/benchmarks/zipper.hs
+++ b/benchmarks/zipper.hs
@@ -19,8 +19,8 @@
       , bench "zipper"            $ nf zipTraverseRezip   ['a'..'z']
       ]
   , bgroup "downward"
-      [ bench "downward _1"       $ nf downwardAndRezip1 (['a'..'z'],['z'..'a'])
-      , bench "fromWithin"        $ nf downwardAndRezip2 (['a'..'z'],['z'..'a'])
+      [ bench "downward _1"       $ nf downwardAndRezip1 (['a'..'z'],['z','y'..'a'])
+      , bench "fromWithin"        $ nf downwardAndRezip2 (['a'..'z'],['z','y'..'a'])
       ]
   ]
 
diff --git a/src/Control/Zipper.hs b/src/Control/Zipper.hs
--- a/src/Control/Zipper.hs
+++ b/src/Control/Zipper.hs
diff --git a/src/Control/Zipper/Internal.hs b/src/Control/Zipper/Internal.hs
--- a/src/Control/Zipper/Internal.hs
+++ b/src/Control/Zipper/Internal.hs
@@ -38,33 +38,35 @@
 import Control.Applicative
 import Control.Category ((>>>))
 import Control.Monad
+import qualified Control.Monad.Fail as Fail
 import Control.Lens.Getter
-import Control.Lens.Indexed
 import Control.Lens.Internal.Context
 import Control.Lens.Internal.Indexed
 import Control.Lens.Lens
 import Control.Lens.Setter
 import Control.Lens.Traversal
 import Control.Lens.Type
+import Data.Foldable.WithIndex
 import Data.Functor.Apply
+import Data.Functor.WithIndex
 import Data.Maybe
-import Data.Monoid (Monoid(..), Last(..))
+import Data.Monoid (Last(..))
 import Data.Profunctor.Unsafe
-
-#if !(MIN_VERSION_base(4,8,0))
-import Data.Foldable
-#endif
+import Data.Traversable.WithIndex
 
 #if !(MIN_VERSION_base(4,11,0))
 import Data.Semigroup (Semigroup(..))
 #endif
 
+#if !MIN_VERSION_lens(5,0,0)
+import qualified Control.Lens.Indexed as Lens
+#endif
+
 -- $setup
 -- >>> :set -XNoOverloadedStrings
 -- >>> import Control.Lens
 -- >>> import Data.Char
-
-{-# ANN module "HLint: ignore Use foldl" #-}
+-- >>> import Data.Maybe (isNothing)
 
 ------------------------------------------------------------------------------
 -- * Jacket
@@ -152,6 +154,12 @@
     go Pure                = pure Pure
   {-# INLINE itraverse #-}
 
+#if !MIN_VERSION_lens(5,0,0)
+instance Lens.FunctorWithIndex     i (Jacket i) where imap = imap
+instance Lens.FoldableWithIndex    i (Jacket i) where ifoldMap = ifoldMap
+instance Lens.TraversableWithIndex i (Jacket i) where itraverse = itraverse
+#endif
+
 instance Semigroup (Jacket i a) where
   l <> r = Ap (size l + size r) (nullLeft l && nullLeft r) (nullRight r && nullRight l) (maximal l <> maximal r) l r
   {-# INLINE (<>) #-}
@@ -185,7 +193,7 @@
 
 instance Apply (Flow i b) where
   (<.>) = (<*>)
-  {- INLINE (<.>) #-}
+  {-# INLINE (<.>) #-}
 
 -- | This is an illegal 'Applicative'.
 instance Applicative (Flow i b) where
@@ -536,15 +544,27 @@
 --
 -- >>> fmap rezip $ zipper "silly" & within traverse >>= jerks rightward 3 <&> focus .~ 'k'
 -- "silky"
-jerks :: Monad m => (a -> m a) -> Int -> a -> m a
+jerks :: Fail.MonadFail m => (a -> m a) -> Int -> a -> m a
 jerks f n0
-  | n0 < 0    = fail "jerks: negative jerk count"
+  | n0 < 0    = \_ -> fail "jerks: negative jerk count"
   | otherwise = go n0
   where
     go 0 a = return a
     go n a = f a >>= go (n - 1)
 {-# INLINE jerks #-}
 
+-- | 'jerksError' is Like 'jerks', but it uses 'error' instead of 'fail' when
+-- the supplied 'Int' is negative. This allows 'jerksError' to have a 'Monad'
+-- constraint instead of the less general 'MonadFail'.
+jerksError :: Monad m => (a -> m a) -> Int -> a -> m a
+jerksError f n0
+  | n0 < 0    = \_ -> error "jerksError: negative jerk count"
+  | otherwise = go n0
+  where
+    go 0 a = return a
+    go n a = f a >>= go (n - 1)
+{-# INLINE jerksError #-}
+
 -- | Returns the number of siblings at the current level in the 'Zipper'.
 --
 -- @'teeth' z '>=' 1@
@@ -591,9 +611,12 @@
 -- Just "now working"
 jerkTo :: MonadPlus m => Int -> (h :> a:@i) -> m (h :> a:@i)
 jerkTo n z = case compare k n of
-  LT -> jerks rightward (n - k) z
+  -- We use jerksError here instead of jerks to avoid incurring a useless
+  -- MonadFail constraint (as we ensure that jerksError is never called with
+  -- a negative Int argument).
+  LT -> jerksError rightward (n - k) z
   EQ -> return z
-  GT -> jerks leftward (k - n) z
+  GT -> jerksError leftward (k - n) z
   where k = tooth z
 {-# INLINE jerkTo #-}
 
diff --git a/tests/doctests.hs b/tests/doctests.hs
deleted file mode 100644
--- a/tests/doctests.hs
+++ /dev/null
@@ -1,25 +0,0 @@
------------------------------------------------------------------------------
--- |
--- Module      :  Main (doctests)
--- Copyright   :  (C) 2012-14 Edward Kmett
--- License     :  BSD-style (see the file LICENSE)
--- Maintainer  :  Edward Kmett <ekmett@gmail.com>
--- Stability   :  provisional
--- Portability :  portable
---
--- This module provides doctests for a project based on the actual versions
--- of the packages it was built with. It requires a corresponding Setup.lhs
--- to be added to the project
------------------------------------------------------------------------------
-module Main where
-
-import Build_doctests (flags, pkgs, module_sources)
-import Data.Foldable (traverse_)
-import Test.DocTest
-
-main :: IO ()
-main = do
-    traverse_ putStrLn args
-    doctest args
-  where
-    args = flags ++ pkgs ++ module_sources
diff --git a/travis/cabal-apt-install b/travis/cabal-apt-install
deleted file mode 100644
--- a/travis/cabal-apt-install
+++ /dev/null
@@ -1,27 +0,0 @@
-#! /bin/bash
-set -eu
-
-APT="sudo apt-get -q -y"
-CABAL_INSTALL_DEPS="cabal install --only-dependencies --force-reinstall"
-
-$APT update
-$APT install dctrl-tools
-
-# Find potential system packages to satisfy cabal dependencies
-deps()
-{
-	local M='^\([^ ]\+\)-[0-9.]\+ (.*$'
-	local G=' -o ( -FPackage -X libghc-\L\1\E-dev )'
-	local E="$($CABAL_INSTALL_DEPS "$@" --dry-run -v 2> /dev/null \
-		| sed -ne "s/$M/$G/p" | sort -u)"
-	grep-aptavail -n -sPackage \( -FNone -X None \) $E | sort -u
-}
-
-$APT install $(deps "$@") libghc-quickcheck2-dev # QuickCheck is special
-$CABAL_INSTALL_DEPS "$@" # Install the rest via Hackage
-
-if ! $APT install hlint ; then
-	$APT install $(deps hlint)
-	cabal install hlint
-fi
-
diff --git a/travis/config b/travis/config
deleted file mode 100644
--- a/travis/config
+++ /dev/null
@@ -1,16 +0,0 @@
--- This provides a custom ~/.cabal/config file for use when hackage is down that should work on unix
---
--- This is particularly useful for travis-ci to get it to stop complaining
--- about a broken build when everything is still correct on our end.
---
--- This uses Luite Stegeman's mirror of hackage provided by his 'hdiff' site instead
---
--- To enable this, uncomment the before_script in .travis.yml
-
-remote-repo: hdiff.luite.com:http://hdiff.luite.com/packages/archive
-remote-repo-cache: ~/.cabal/packages
-world-file: ~/.cabal/world
-build-summary: ~/.cabal/logs/build.log
-remote-build-reporting: anonymous
-install-dirs user
-install-dirs global
diff --git a/zippers.cabal b/zippers.cabal
--- a/zippers.cabal
+++ b/zippers.cabal
@@ -1,6 +1,6 @@
 name:          zippers
 category:      zippers
-version:       0.2.5
+version:       0.3.2
 license:       BSD3
 cabal-version: >= 1.10
 license-file:  LICENSE
@@ -12,61 +12,43 @@
 copyright:     Copyright (C) 2013 Edward A. Kmett
 synopsis:      Traversal based zippers
 description:   Traversal based zippers.
-build-type:    Custom
-tested-with:   GHC == 7.4.2
-             , GHC == 7.6.3
-             , GHC == 7.8.4
-             , GHC == 7.10.3
-             , GHC == 8.0.2
+build-type:    Simple
+tested-with:   GHC == 8.0.2
              , GHC == 8.2.2
-             , GHC == 8.4.1
+             , GHC == 8.4.4
+             , GHC == 8.6.5
+             , GHC == 8.8.4
+             , GHC == 8.10.7
+             , GHC == 9.0.1
+             , GHC == 9.2.1
 
 extra-source-files:
   .ghci
   .gitignore
-  .travis.yml
+  .hlint.yaml
   .vim.custom
   CHANGELOG.markdown
-  HLint.hs
   README.markdown
-  Warning.hs
-  travis/cabal-apt-install
-  travis/config
 
 source-repository head
   type: git
   location: https://github.com/ekmett/zippers
 
-custom-setup
-  setup-depends:
-    base          >= 4 && < 5,
-    Cabal,
-    cabal-doctest >= 1 && < 1.1
-
 library
   hs-source-dirs: src
   default-language: Haskell2010
   ghc-options: -Wall
   build-depends:
-    base >= 4.5 && < 5,
-    lens >= 4 && < 5,
+    base >= 4.9 && < 5,
+    fail == 4.9.*,
+    indexed-traversable >= 0.1.1 && < 0.2,
+    lens >= 4 && < 6,
     profunctors >= 4 && < 6,
     semigroups >= 0.16 && < 1,
     semigroupoids >= 4 && < 6
   exposed-modules:
     Control.Zipper
     Control.Zipper.Internal
-
-test-suite doctests
-  type:    exitcode-stdio-1.0
-  main-is: doctests.hs
-  default-language: Haskell2010
-  build-depends:
-    base,
-    doctest >= 0.11.1 && < 0.14,
-    zippers
-  ghc-options: -Wall -threaded
-  hs-source-dirs: tests
 
 benchmark zipper
   type:             exitcode-stdio-1.0