diff --git a/.gitignore b/.gitignore
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,6 @@
-dist/
-dist-newstyle/
-shell.nix
+*~
+/dist/
+/dist-newstyle/
 cabal.project.local
+shell.nix
+/result/
diff --git a/.travis.yml b/.travis.yml
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,111 +1,149 @@
 # This Travis job script has been generated by a script via
 #
-#   runghc make_travis_yml_2.hs 'lens-toml-parser.cabal'
+#   haskell-ci 'lens-toml-parser.cabal' '--output' '.travis.yml'
 #
+# To regenerate the script (for example after adjusting tested-with) run
+#
+#   haskell-ci regenerate
+#
 # For more information, see https://github.com/haskell-CI/haskell-ci
 #
+# version: 0.10
+#
+version: ~> 1.0
 language: c
-sudo: false
-
+os: linux
+dist: xenial
 git:
-  submodules: false  # whether to recursively clone submodules
-
+  # whether to recursively clone submodules
+  submodules: false
 cache:
   directories:
     - $HOME/.cabal/packages
     - $HOME/.cabal/store
-
+    - $HOME/.hlint
 before_cache:
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/build-reports.log
+  - rm -fv $CABALHOME/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
-
-matrix:
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/00-index.*
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/*.json
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.cache
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.tar
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.tar.idx
+  - rm -rfv $CABALHOME/packages/head.hackage
+jobs:
   include:
-    - compiler: "ghc-8.6.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.4,ghc-8.6.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.4.4"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.4,ghc-8.4.4], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.2.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.4,ghc-8.2.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.0.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.4,ghc-8.0.2], sources: [hvr-ghc]}}
-
+    - compiler: ghc-8.8.3
+      addons: {"apt":{"sources":[{"sourceline":"deb http://ppa.launchpad.net/hvr/ghc/ubuntu xenial main","key_url":"https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x063dab2bdc0b3f9fcebc378bff3aeacef6f88286"}],"packages":["ghc-8.8.3","cabal-install-3.2"]}}
+      os: linux
+    - compiler: ghc-8.6.5
+      addons: {"apt":{"sources":[{"sourceline":"deb http://ppa.launchpad.net/hvr/ghc/ubuntu xenial main","key_url":"https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x063dab2bdc0b3f9fcebc378bff3aeacef6f88286"}],"packages":["ghc-8.6.5","cabal-install-3.2"]}}
+      os: linux
+    - compiler: ghc-8.4.4
+      addons: {"apt":{"sources":[{"sourceline":"deb http://ppa.launchpad.net/hvr/ghc/ubuntu xenial main","key_url":"https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x063dab2bdc0b3f9fcebc378bff3aeacef6f88286"}],"packages":["ghc-8.4.4","cabal-install-3.2"]}}
+      os: linux
+    - compiler: ghc-8.2.2
+      addons: {"apt":{"sources":[{"sourceline":"deb http://ppa.launchpad.net/hvr/ghc/ubuntu xenial main","key_url":"https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x063dab2bdc0b3f9fcebc378bff3aeacef6f88286"}],"packages":["ghc-8.2.2","cabal-install-3.2"]}}
+      os: linux
+    - compiler: ghc-8.0.2
+      addons: {"apt":{"sources":[{"sourceline":"deb http://ppa.launchpad.net/hvr/ghc/ubuntu xenial main","key_url":"https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x063dab2bdc0b3f9fcebc378bff3aeacef6f88286"}],"packages":["ghc-8.0.2","cabal-install-3.2"]}}
+      os: linux
 before_install:
-  - HC=${CC}
-  - HCPKG=${HC/ghc/ghc-pkg}
+  - HC=$(echo "/opt/$CC/bin/ghc" | sed 's/-/\//')
+  - WITHCOMPILER="-w $HC"
+  - HADDOCK=$(echo "/opt/$CC/bin/haddock" | sed 's/-/\//')
+  - HCPKG="$HC-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/') ))
+  - CABAL=/opt/ghc/bin/cabal
+  - CABALHOME=$HOME/.cabal
+  - export PATH="$CABALHOME/bin:$PATH"
+  - TOP=$(pwd)
+  - "HCNUMVER=$(${HC} --numeric-version|perl -ne '/^(\\d+)\\.(\\d+)\\.(\\d+)(\\.(\\d+))?$/; print(10000 * $1 + 100 * $2 + ($3 == 0 ? $5 != 1 : $3))')"
   - echo $HCNUMVER
-
+  - CABAL="$CABAL -vnormal+nowrap"
+  - set -o pipefail
+  - TEST=--enable-tests
+  - BENCH=--enable-benchmarks
+  - HEADHACKAGE=false
+  - rm -f $CABALHOME/config
+  - |
+    echo "verbose: normal +nowrap +markoutput"          >> $CABALHOME/config
+    echo "remote-build-reporting: anonymous"            >> $CABALHOME/config
+    echo "write-ghc-environment-files: always"          >> $CABALHOME/config
+    echo "remote-repo-cache: $CABALHOME/packages"       >> $CABALHOME/config
+    echo "logs-dir:          $CABALHOME/logs"           >> $CABALHOME/config
+    echo "world-file:        $CABALHOME/world"          >> $CABALHOME/config
+    echo "extra-prog-path:   $CABALHOME/bin"            >> $CABALHOME/config
+    echo "symlink-bindir:    $CABALHOME/bin"            >> $CABALHOME/config
+    echo "installdir:        $CABALHOME/bin"            >> $CABALHOME/config
+    echo "build-summary:     $CABALHOME/logs/build.log" >> $CABALHOME/config
+    echo "store-dir:         $CABALHOME/store"          >> $CABALHOME/config
+    echo "install-dirs user"                            >> $CABALHOME/config
+    echo "  prefix: $CABALHOME"                         >> $CABALHOME/config
+    echo "repository hackage.haskell.org"               >> $CABALHOME/config
+    echo "  url: http://hackage.haskell.org/"           >> $CABALHOME/config
 install:
-  - cabal --version
+  - ${CABAL} --version
   - echo "$(${HC} --version) [$(${HC} --print-project-git-commit-id 2> /dev/null || echo '?')]"
-  - BENCH=${BENCH---enable-benchmarks}
-  - TEST=${TEST---enable-tests}
-  - HADDOCK=${HADDOCK-true}
-  - UNCONSTRAINED=${UNCONSTRAINED-true}
-  - NOINSTALLEDCONSTRAINTS=${NOINSTALLEDCONSTRAINTS-false}
-  - GHCHEAD=${GHCHEAD-false}
-  - travis_retry cabal update -v
-  - "sed -i.bak 's/^jobs:/-- jobs:/' ${HOME}/.cabal/config"
-  - rm -fv cabal.project cabal.project.local
-  - grep -Ev -- '^\s*--' ${HOME}/.cabal/config | grep -Ev '^\s*$'
-  - "printf 'packages: \".\"\\n' > cabal.project"
-  - touch cabal.project.local
-  - "if ! $NOINSTALLEDCONSTRAINTS; then for pkg in $($HCPKG list --simple-output); do echo $pkg  | grep -vw -- lens-toml-parser | sed 's/^/constraints: /' | sed 's/-[^-]*$/ installed/' >> cabal.project.local; done; fi"
+  - |
+    echo "program-default-options"                >> $CABALHOME/config
+    echo "  ghc-options: $GHCJOBS +RTS -M6G -RTS" >> $CABALHOME/config
+  - cat $CABALHOME/config
+  - rm -fv cabal.project cabal.project.local cabal.project.freeze
+  - travis_retry ${CABAL} v2-update -v
+  # Generate cabal.project
+  - rm -rf cabal.project cabal.project.local cabal.project.freeze
+  - touch cabal.project
+  - |
+    echo "packages: ." >> cabal.project
+  - if [ $HCNUMVER -ge 80200 ] ; then echo 'package lens-toml-parser' >> cabal.project ; fi
+  - "if [ $HCNUMVER -ge 80200 ] ; then echo '  ghc-options: -Werror=missing-methods' >> cabal.project ; fi"
+  - |
+  - "for pkg in $($HCPKG list --simple-output); do echo $pkg | sed 's/-[^-]*$//' | (grep -vE -- '^(lens-toml-parser)$' || true) | sed 's/^/constraints: /' | sed 's/$/ installed/' >> cabal.project.local; done"
   - cat cabal.project || true
   - cat cabal.project.local || true
-  - if [ -f "./configure.ac" ]; then
-      (cd "." && autoreconf -i);
-    fi
-  - rm -f cabal.project.freeze
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} --project-file="cabal.project" --dep -j2 all
-  - cabal new-build -w ${HC} --disable-tests --disable-benchmarks --project-file="cabal.project" --dep -j2 all
-  - rm -rf .ghc.environment.* "."/dist
-  - DISTDIR=$(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.
+  - if [ -f "./configure.ac" ]; then (cd "." && autoreconf -i); fi
+  - ${CABAL} v2-freeze $WITHCOMPILER ${TEST} ${BENCH}
+  - "cat cabal.project.freeze | sed -E 's/^(constraints: *| *)//' | sed 's/any.//'"
+  - rm  cabal.project.freeze
+  - travis_wait 40 ${CABAL} v2-build $WITHCOMPILER ${TEST} ${BENCH} --dep -j2 all
+  - travis_wait 40 ${CABAL} v2-build $WITHCOMPILER --disable-tests --disable-benchmarks --dep -j2 all
 script:
-  # test that source-distributions can be generated
-  - cabal new-sdist all
+  - DISTDIR=$(mktemp -d /tmp/dist-test.XXXX)
+  # Packaging...
+  - ${CABAL} v2-sdist all
+  # Unpacking...
   - mv dist-newstyle/sdist/*.tar.gz ${DISTDIR}/
   - cd ${DISTDIR} || false
-  - find . -maxdepth 1 -name '*.tar.gz' -exec tar -xvf '{}' \;
-  - "printf 'packages: lens-toml-parser-*/*.cabal\\n' > cabal.project"
-  - touch cabal.project.local
-  - "if ! $NOINSTALLEDCONSTRAINTS; then for pkg in $($HCPKG list --simple-output); do echo $pkg  | grep -vw -- lens-toml-parser | sed 's/^/constraints: /' | sed 's/-[^-]*$/ installed/' >> cabal.project.local; done; fi"
+  - find . -maxdepth 1 -type f -name '*.tar.gz' -exec tar -xvf '{}' \;
+  - find . -maxdepth 1 -type f -name '*.tar.gz' -exec rm       '{}' \;
+  - PKGDIR_lens_toml_parser="$(find . -maxdepth 1 -type d -regex '.*/lens-toml-parser-[0-9.]*')"
+  # Generate cabal.project
+  - rm -rf cabal.project cabal.project.local cabal.project.freeze
+  - touch cabal.project
+  - |
+    echo "packages: ${PKGDIR_lens_toml_parser}" >> cabal.project
+  - if [ $HCNUMVER -ge 80200 ] ; then echo 'package lens-toml-parser' >> cabal.project ; fi
+  - "if [ $HCNUMVER -ge 80200 ] ; then echo '  ghc-options: -Werror=missing-methods' >> cabal.project ; fi"
+  - |
+  - "for pkg in $($HCPKG list --simple-output); do echo $pkg | sed 's/-[^-]*$//' | (grep -vE -- '^(lens-toml-parser)$' || true) | sed 's/^/constraints: /' | sed 's/$/ installed/' >> cabal.project.local; done"
   - cat cabal.project || true
   - cat cabal.project.local || true
+  # Building...
   # this builds all libraries and executables (without tests/benchmarks)
-  - cabal new-build -w ${HC} --disable-tests --disable-benchmarks all
-
+  - ${CABAL} v2-build $WITHCOMPILER --disable-tests --disable-benchmarks all
+  # Building with tests and benchmarks...
   # 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 lens-toml-parser-* && cabal check)
-
-  # haddock
-  - if $HADDOCK; then cabal new-haddock -w ${HC} ${TEST} ${BENCH} all; else echo "Skipping haddock generation";fi
-
-  # Build without installed constraints for packages in global-db
-  - if $UNCONSTRAINED; then rm -f cabal.project.local; echo cabal new-build -w ${HC} --disable-tests --disable-benchmarks all; else echo "Not building without installed constraints"; fi
+  - ${CABAL} v2-build $WITHCOMPILER ${TEST} ${BENCH} all
+  # Testing...
+  - ${CABAL} v2-test $WITHCOMPILER ${TEST} ${BENCH} all
+  # cabal check...
+  - (cd ${PKGDIR_lens_toml_parser} && ${CABAL} -vnormal check)
+  # haddock...
+  - ${CABAL} v2-haddock $WITHCOMPILER --with-haddock $HADDOCK ${TEST} ${BENCH} all
+  # Building without installed constraints for packages in global-db...
+  - rm -f cabal.project.local
+  - ${CABAL} v2-build $WITHCOMPILER --disable-tests --disable-benchmarks all
 
-# REGENDATA ["lens-toml-parser.cabal"]
+# REGENDATA ("0.10",["lens-toml-parser.cabal","--output",".travis.yml"])
 # EOF
diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -18,3 +18,7 @@
 
 * Loosened constraints on `base`, `containers`, `profunctors`, and `time`.
 * Tweaked tests/Main.hs to appease hlint.
+
+## 0.1.0.4  -- 2020-05-05
+
+* Loosened constraints on `base`, `hlint`, `profunctors`, and `time`.
diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2017-2018 Henry Till
+Copyright (c) 2017-2020 Henry Till
 
 Permission to use, copy, modify, and/or distribute this software for any purpose
 with or without fee is hereby granted, provided that the above copyright notice
diff --git a/lens-toml-parser.cabal b/lens-toml-parser.cabal
--- a/lens-toml-parser.cabal
+++ b/lens-toml-parser.cabal
@@ -2,7 +2,7 @@
 -- documentation, see http://haskell.org/cabal/users-guide/
 
 name:                lens-toml-parser
-version:             0.1.0.3
+version:             0.1.0.4
 synopsis:            Lenses for toml-parser
 description:         This library provides lenses for toml-parser.
 license:             ISC
@@ -10,11 +10,11 @@
 author:              Henry Till
 maintainer:          henrytill@gmail.com
 homepage:            https://github.com/xngns/lens-toml-parser
-copyright:           Copyright (c) 2017-2018, Henry Till
+copyright:           Copyright (c) 2017-2020, Henry Till
 category:            Language, Lenses
 build-type:          Simple
 cabal-version:       >=1.10
-tested-with:         GHC == 8.0.2, GHC == 8.2.2, GHC == 8.4.4, GHC == 8.6.2
+tested-with:         GHC == 8.0.2, GHC == 8.2.2, GHC == 8.4.4, GHC == 8.6.5, GHC == 8.8.3
 
 extra-source-files:
   .gitignore
@@ -31,10 +31,10 @@
   exposed-modules:     TOML.Lens
   -- other-modules:       
   -- other-extensions:    
-  build-depends:       base        >=4.8 && <4.13
+  build-depends:       base        >=4.8 && <5
                      , text        >=1.2 && <1.3
-                     , time        >=1.5 && <1.10
-                     , profunctors >=5.2 && <5.4
+                     , time        >=1.5 && <1.11
+                     , profunctors >=5.2 && <5.6
                      , toml-parser >=0.1 && <0.2
   hs-source-dirs:      src
   default-language:    Haskell2010
@@ -43,7 +43,7 @@
 test-suite tests
   type:                exitcode-stdio-1.0
   main-is:             Main.hs
-  build-depends:       base        >=4.8 && <4.13
+  build-depends:       base        >=4.8 && <5
                      , containers  >=0.5 && <0.7
                      , text        >=1.2 && <1.3
                      , dwergaz     >=0.2 && <0.3
@@ -58,7 +58,7 @@
   type:                exitcode-stdio-1.0
   main-is:             HLint.hs
   build-depends:       base
-                     , hlint >= 1.9 && <2.2
+                     , hlint >= 1.9 && <3
   hs-source-dirs:      tests
   default-language:    Haskell2010
   ghc-options:         -Wall
diff --git a/src/TOML/Lens.hs b/src/TOML/Lens.hs
--- a/src/TOML/Lens.hs
+++ b/src/TOML/Lens.hs
@@ -1,7 +1,7 @@
 -- |
 -- Module      : TOML.Lens
 -- Description : Lenses for toml-parser
--- Copyright   : (c) 2017-2018, Henry Till
+-- Copyright   : (c) 2017-2020, Henry Till
 -- License     : ISC
 -- Maintainer  : henrytill@gmail.com
 -- Stability   : experimental