diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
--- a/.travis.yml
+++ /dev/null
@@ -1,146 +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:
-      - "\x0313hybrid-vectors\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
-
-matrix:
-  include:
-    - compiler: "ghc-7.0.4"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.0,ghc-7.0.4], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.2.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.0,ghc-7.2.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.4.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,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: [ghc-ppa-tools,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: [ghc-ppa-tools,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: [ghc-ppa-tools,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: [ghc-ppa-tools,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: [ghc-ppa-tools,cabal-install-2.0,ghc-8.2.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.4.1"
-      env: GHCHEAD=true
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-head,ghc-8.4.1], sources: [hvr-ghc]}}
-    - compiler: "ghc-head"
-      env: GHCHEAD=true
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-head,ghc-head], sources: [hvr-ghc]}}
-
-  allow_failures:
-    - compiler: "ghc-7.0.4"
-    - compiler: "ghc-7.2.2"
-    - 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: \".\"\\n' > cabal.project"
-  - cat cabal.project
-  - if [ -f "./configure.ac" ]; then
-      (cd "." && autoreconf -i);
-    fi
-  - rm -f cabal.project.freeze
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} --project-file="cabal.project" --dep -j2 all
-  - rm -rf "."/.ghc.environment.* "."/dist
-  - DISTDIR=$(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.
-script:
-  # test that source-distributions can be generated
-  - (cd "." && cabal sdist)
-  - mv "."/dist/hybrid-vectors-*.tar.gz ${DISTDIR}/
-  - cd ${DISTDIR} || false
-  - find . -maxdepth 1 -name '*.tar.gz' -exec tar -xvf '{}' \;
-  - "printf 'packages: hybrid-vectors-*/*.cabal\\n' > cabal.project"
-  - cat cabal.project
-
-
-  # build & run tests, build benchmarks
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} all
-
-  # cabal check
-  - (cd hybrid-vectors-* && cabal check)
-
-  # haddock
-  - rm -rf ./dist-newstyle
-  - if $HADDOCK; then cabal new-haddock -w ${HC} ${TEST} ${BENCH} all; else echo "Skipping haddock generation";fi
-
-# REGENDATA ["-o",".travis.yml","--irc-channel=irc.freenode.org#haskell-lens","--no-no-tests-no-bench","--no-installed","cabal.project"]
-# EOF
diff --git a/hybrid-vectors.cabal b/hybrid-vectors.cabal
--- a/hybrid-vectors.cabal
+++ b/hybrid-vectors.cabal
@@ -1,8 +1,8 @@
 name:          hybrid-vectors
 category:      Data, Vector
-version:       0.2.2
+version:       0.2.3
 license:       BSD3
-cabal-version: >= 1.6
+cabal-version: >= 1.10
 license-file:  LICENSE
 author:        Edward A. Kmett
 maintainer:    Edward A. Kmett <ekmett@gmail.com>
@@ -14,7 +14,6 @@
 synopsis:      Hybrid vectors e.g. Mixed Boxed/Unboxed vectors
 extra-source-files:
   .ghci
-  .travis.yml
   .gitignore
   .vim.custom
 description: Hybrid vectors e.g. Mixed Boxed/Unboxed vectors.
@@ -26,7 +25,12 @@
              , GHC == 7.10.3
              , 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 == 9.0.2
+             , GHC == 9.2.2
 
 source-repository head
   type: git
@@ -36,8 +40,8 @@
   build-depends:
     base          >= 4       && < 5,
     deepseq       >= 1.1     && < 1.5,
-    primitive     >= 0.5     && < 0.7,
-    vector        >= 0.10    && < 0.13,
+    primitive     >= 0.5     && < 0.8,
+    vector        >= 0.10    && < 0.14,
     semigroups    >= 0.9     && < 1
 
   hs-source-dirs: src
@@ -48,6 +52,10 @@
     Data.Vector.Hybrid.Mutable
 
   ghc-options: -Wall -O2
+  default-language: Haskell2010
 
   if impl(ghc<6.13)
     Ghc-Options: -finline-if-enough-args -fno-method-sharing
+
+  if impl(ghc >= 8.6)
+    ghc-options: -Wno-star-is-type
diff --git a/src/Data/Vector/Hybrid/Internal.hs b/src/Data/Vector/Hybrid/Internal.hs
--- a/src/Data/Vector/Hybrid/Internal.hs
+++ b/src/Data/Vector/Hybrid/Internal.hs
@@ -1,6 +1,7 @@
 {-# LANGUAGE CPP, DeriveDataTypeable, FlexibleInstances, GADTs        #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving, KindSignatures               #-}
 {-# LANGUAGE MultiParamTypeClasses, ScopedTypeVariables, TypeFamilies #-}
+{-# LANGUAGE TypeOperators                                            #-}
 {-# LANGUAGE UndecidableInstances                                     #-}
 
 #ifndef MIN_VERSION_base
@@ -140,12 +141,14 @@
   {-# INLINE elemseq #-}
 
 instance (G.Vector u a, G.Vector v b, c ~ (a, b)) => Semigroup (Vector u v c) where
-  (<>) = mappend
+  (<>) = (G.++)
   sconcat = mconcat . F.toList
 
 instance (G.Vector u a, G.Vector v b, c ~ (a, b)) => Monoid (Vector u v c) where
+#if !(MIN_VERSION_base(4,11,0))
   mappend = (G.++)
   {-# INLINE mappend #-}
+#endif
   mempty = G.empty
   {-# INLINE mempty #-}
   mconcat = G.concat
@@ -162,7 +165,7 @@
   gfoldl       = G.gfoldl
   toConstr _   = error "toConstr" -- TODO: virtual constructor
   gunfold _ _  = error "gunfold"  -- TODO: virtual constructor
-  dataTypeOf _ = G.mkType "Data.Vector.Hybrid.Vector"
+  dataTypeOf _ = mkNoRepType "Data.Vector.Hybrid.Vector"
   dataCast1    = G.dataCast
 
 
