diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
--- a/.travis.yml
+++ /dev/null
@@ -1,175 +0,0 @@
-# This Travis job script has been generated by a script via
-#
-#   haskell-ci '--output=.travis.yml' '--config=cabal.haskell-ci' 'cabal.project'
-#
-# 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
-os: linux
-dist: xenial
-git:
-  # whether to recursively clone submodules
-  submodules: false
-notifications:
-  irc:
-    channels:
-      - irc.freenode.org#haskell-lens
-    skip_join: true
-    template:
-      - "\x0313free\x03/\x0306%{branch}\x03 \x0314%{commit}\x03 %{build_url} %{message}"
-cache:
-  directories:
-    - $HOME/.cabal/packages
-    - $HOME/.cabal/store
-    - $HOME/.hlint
-before_cache:
-  - rm -fv $CABALHOME/packages/hackage.haskell.org/build-reports.log
-  # remove files that are regenerated by 'cabal update'
-  - 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-8.10.1
-      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-8.10.1","cabal-install-3.2"]}}
-      os: linux
-    - 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
-    - compiler: ghc-7.10.3
-      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-7.10.3","cabal-install-3.2"]}}
-      os: linux
-    - compiler: ghc-7.8.4
-      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-7.8.4","cabal-install-3.2"]}}
-      os: linux
-    - compiler: ghc-7.6.3
-      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-7.6.3","cabal-install-3.2"]}}
-      os: linux
-    - compiler: ghc-7.4.2
-      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-7.4.2","cabal-install-3.2"]}}
-      os: linux
-before_install:
-  - HC=$(echo "/opt/$CC/bin/ghc" | sed 's/-/\//')
-  - WITHCOMPILER="-w $HC"
-  - HADDOCK=$(echo "/opt/$CC/bin/haddock" | sed 's/-/\//')
-  - HCPKG="$HC-pkg"
-  - unset CC
-  - 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:
-  - ${CABAL} --version
-  - echo "$(${HC} --version) [$(${HC} --print-project-git-commit-id 2> /dev/null || echo '?')]"
-  - |
-    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
-    echo "packages: ./examples" >> cabal.project
-  - if [ $HCNUMVER -ge 80200 ] ; then echo 'package free' >> cabal.project ; fi
-  - "if [ $HCNUMVER -ge 80200 ] ; then echo '  ghc-options: -Werror=missing-methods' >> cabal.project ; fi"
-  - if [ $HCNUMVER -ge 80200 ] ; then echo 'package free-examples' >> cabal.project ; fi
-  - "if [ $HCNUMVER -ge 80200 ] ; then echo '  ghc-options: -Werror=missing-methods' >> cabal.project ; fi"
-  - |
-    echo "package free-examples"     >> cabal.project
-    echo "  flags: -mandelbrot-iter" >> cabal.project
-  - "for pkg in $($HCPKG list --simple-output); do echo $pkg | sed 's/-[^-]*$//' | (grep -vE -- '^(free|free-examples)$' || true) | sed 's/^/constraints: /' | sed 's/$/ installed/' >> cabal.project.local; done"
-  - cat cabal.project || true
-  - cat cabal.project.local || true
-  - if [ -f "./configure.ac" ]; then (cd "." && autoreconf -i); fi
-  - if [ -f "./examples/configure.ac" ]; then (cd "./examples" && 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} ${BENCH} --dep -j2 all
-script:
-  - DISTDIR=$(mktemp -d /tmp/dist-test.XXXX)
-  # Packaging...
-  - ${CABAL} v2-sdist all
-  # Unpacking...
-  - mv dist-newstyle/sdist/*.tar.gz ${DISTDIR}/
-  - cd ${DISTDIR} || false
-  - find . -maxdepth 1 -type f -name '*.tar.gz' -exec tar -xvf '{}' \;
-  - find . -maxdepth 1 -type f -name '*.tar.gz' -exec rm       '{}' \;
-  - PKGDIR_free="$(find . -maxdepth 1 -type d -regex '.*/free-[0-9.]*')"
-  - PKGDIR_free_examples="$(find . -maxdepth 1 -type d -regex '.*/free-examples-[0-9.]*')"
-  # Generate cabal.project
-  - rm -rf cabal.project cabal.project.local cabal.project.freeze
-  - touch cabal.project
-  - |
-    echo "packages: ${PKGDIR_free}" >> cabal.project
-    echo "packages: ${PKGDIR_free_examples}" >> cabal.project
-  - if [ $HCNUMVER -ge 80200 ] ; then echo 'package free' >> cabal.project ; fi
-  - "if [ $HCNUMVER -ge 80200 ] ; then echo '  ghc-options: -Werror=missing-methods' >> cabal.project ; fi"
-  - if [ $HCNUMVER -ge 80200 ] ; then echo 'package free-examples' >> cabal.project ; fi
-  - "if [ $HCNUMVER -ge 80200 ] ; then echo '  ghc-options: -Werror=missing-methods' >> cabal.project ; fi"
-  - |
-    echo "package free-examples"     >> cabal.project
-    echo "  flags: -mandelbrot-iter" >> cabal.project
-  - "for pkg in $($HCPKG list --simple-output); do echo $pkg | sed 's/-[^-]*$//' | (grep -vE -- '^(free|free-examples)$' || true) | sed 's/^/constraints: /' | sed 's/$/ installed/' >> cabal.project.local; done"
-  - cat cabal.project || true
-  - cat cabal.project.local || true
-  # Building with tests and benchmarks...
-  # build & run tests, build benchmarks
-  - ${CABAL} v2-build $WITHCOMPILER ${TEST} ${BENCH} all
-  # cabal check...
-  - (cd ${PKGDIR_free} && ${CABAL} -vnormal check)
-  - (cd ${PKGDIR_free_examples} && ${CABAL} -vnormal check)
-  # haddock...
-  - ${CABAL} v2-haddock $WITHCOMPILER --with-haddock $HADDOCK ${TEST} ${BENCH} all
-
-# REGENDATA ("0.10",["--output=.travis.yml","--config=cabal.haskell-ci","cabal.project"])
-# EOF
diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,7 @@
+5.1.6 [2020.12.31]
+------------------
+* Explicitly mark modules as `Safe`.
+
 5.1.5 [2020.12.16]
 ------------------
 * Move `indexed-traversable` (`FunctorWithIndex` etc) instances from `lens`.
diff --git a/README.markdown b/README.markdown
--- a/README.markdown
+++ b/README.markdown
@@ -1,7 +1,7 @@
 free
 ====
 
-[![Hackage](https://img.shields.io/hackage/v/free.svg)](https://hackage.haskell.org/package/free) [![Build Status](https://secure.travis-ci.org/ekmett/free.png?branch=master)](http://travis-ci.org/ekmett/free)
+[![Hackage](https://img.shields.io/hackage/v/free.svg)](https://hackage.haskell.org/package/free) [![Build Status](https://github.com/ekmett/free/workflows/Haskell-CI/badge.svg)](https://github.com/ekmett/free/actions?query=workflow%3AHaskell-CI)
 
 This package provides a common definitions for working with free monads, free applicatives, and cofree comonads in Haskell.
 
diff --git a/free.cabal b/free.cabal
--- a/free.cabal
+++ b/free.cabal
@@ -1,6 +1,6 @@
 name:          free
 category:      Control, Monads
-version:       5.1.5
+version:       5.1.6
 license:       BSD3
 cabal-version: 1.18
 license-file:  LICENSE
@@ -46,7 +46,6 @@
   .ghci
   .gitignore
   .hlint.yaml
-  .travis.yml
   .vim.custom
   README.markdown
   CHANGELOG.markdown
@@ -81,25 +80,40 @@
     GADTs
 
   build-depends:
-    base                 == 4.*,
-    comonad              >= 4 && < 6,
-    containers           < 0.7,
-    distributive         >= 0.2.1,
-    exceptions           >= 0.6 && < 0.11,
-    indexed-traversable  >= 0.1 && < 0.2,
-    mtl                  >= 2.0.1.0 && < 2.3,
-    profunctors          >= 4 && < 6,
-    semigroupoids        >= 4 && < 6,
-    th-abstraction       >= 0.4 && < 0.5,
-    transformers         >= 0.2.0   && < 0.6,
-    transformers-base    >= 0.4 && < 0.5,
+    base                 >= 4.5     && < 5,
+    comonad              >= 5.0.8   && < 6,
+    containers           >= 0.3     && < 0.7,
+    distributive         >= 0.5.2   && < 1,
+    exceptions           >= 0.10.4  && < 0.11,
+    indexed-traversable  >= 0.1.1   && < 0.2,
+    semigroupoids        >= 5.3.5   && < 6,
+    th-abstraction       >= 0.4.2.0 && < 0.5,
+    transformers         >= 0.3     && < 0.6,
+    transformers-base    >= 0.4.5.2 && < 0.5,
     template-haskell     >= 2.7.0.0 && < 2.18
 
+  -- GHC-7.8 bundles transformers-0.3,
+  -- mtl-2.2.* requires transformers >=0.4
+  if impl(ghc >=7.10)
+    build-depends:
+      mtl               >= 2.2.2 && < 2.3
+  else
+    build-depends:
+      mtl               >= 2.1.3.1 && < 2.3
+
+  -- recent profunctors dropped support for GHCs older than 7.8
+  if impl(ghc >=7.8)
+    build-depends:
+      profunctors >= 5.6.1 && < 6
+  else
+    build-depends:
+      profunctors >= 5.2.2 && < 5.3
+
   if !impl(ghc >= 8.2)
-    build-depends: bifunctors >= 4 && < 6
+    build-depends: bifunctors >= 5.5.9 && < 6
 
   if !impl(ghc >= 8.0)
-    build-depends: semigroups >= 0.8.3.1 && < 1
+    build-depends: semigroups >= 0.18.5 && < 1
 
   -- Ensure Data.Functor.Classes is always available
   if impl(ghc >= 7.10)
@@ -141,3 +155,8 @@
       ghc-options: -Wnoncanonical-monadfail-instances
   else
     build-depends: fail == 4.9.*
+
+  if impl(ghc >= 9.0)
+    -- these flags may abort compilation with GHC-8.10
+    -- https://gitlab.haskell.org/ghc/ghc/-/merge_requests/3295
+    ghc-options: -Winferred-safe-imports -Wmissing-safe-haskell-mode
diff --git a/src/Control/Alternative/Free.hs b/src/Control/Alternative/Free.hs
--- a/src/Control/Alternative/Free.hs
+++ b/src/Control/Alternative/Free.hs
@@ -4,8 +4,11 @@
 {-# LANGUAGE ScopedTypeVariables #-}
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
-{-# OPTIONS_GHC -Wall #-}
 #include "free-common.h"
 
 -----------------------------------------------------------------------------
diff --git a/src/Control/Alternative/Free/Final.hs b/src/Control/Alternative/Free/Final.hs
--- a/src/Control/Alternative/Free/Final.hs
+++ b/src/Control/Alternative/Free/Final.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE CPP #-}
 {-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE Safe #-}
 
 -----------------------------------------------------------------------------
 -- |
diff --git a/src/Control/Applicative/Free.hs b/src/Control/Applicative/Free.hs
--- a/src/Control/Applicative/Free.hs
+++ b/src/Control/Applicative/Free.hs
@@ -3,8 +3,11 @@
 {-# LANGUAGE GADTs #-}
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
-{-# OPTIONS_GHC -Wall #-}
 #include "free-common.h"
 
 -----------------------------------------------------------------------------
diff --git a/src/Control/Applicative/Free/Fast.hs b/src/Control/Applicative/Free/Fast.hs
--- a/src/Control/Applicative/Free/Fast.hs
+++ b/src/Control/Applicative/Free/Fast.hs
@@ -3,12 +3,13 @@
 {-# LANGUAGE RankNTypes         #-}
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
-{-# OPTIONS_GHC -Wall #-}
+#include "free-common.h"
 
-#ifndef MIN_VERSION_base
-#define MIN_VERSION_base(x,y,z) 1
-#endif
 --------------------------------------------------------------------------------
 -- |
 -- A faster free applicative.
diff --git a/src/Control/Applicative/Free/Final.hs b/src/Control/Applicative/Free/Final.hs
--- a/src/Control/Applicative/Free/Final.hs
+++ b/src/Control/Applicative/Free/Final.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE CPP #-}
 {-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE Safe #-}
 #include "free-common.h"
 
 -----------------------------------------------------------------------------
diff --git a/src/Control/Applicative/Trans/Free.hs b/src/Control/Applicative/Trans/Free.hs
--- a/src/Control/Applicative/Trans/Free.hs
+++ b/src/Control/Applicative/Trans/Free.hs
@@ -3,8 +3,11 @@
 {-# LANGUAGE GADTs #-}
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
-{-# OPTIONS_GHC -Wall #-}
 #include "free-common.h"
 
 -----------------------------------------------------------------------------
diff --git a/src/Control/Comonad/Cofree.hs b/src/Control/Comonad/Cofree.hs
--- a/src/Control/Comonad/Cofree.hs
+++ b/src/Control/Comonad/Cofree.hs
@@ -7,8 +7,13 @@
 {-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE StandaloneDeriving #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
 #include "free-common.h"
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Control.Comonad.Cofree
diff --git a/src/Control/Comonad/Cofree/Class.hs b/src/Control/Comonad/Cofree/Class.hs
--- a/src/Control/Comonad/Cofree/Class.hs
+++ b/src/Control/Comonad/Cofree/Class.hs
@@ -2,8 +2,10 @@
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE FunctionalDependencies #-}
 {-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE Safe #-}
 {-# LANGUAGE UndecidableInstances #-}
 #include "free-common.h"
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Control.Comonad.Cofree.Class
diff --git a/src/Control/Comonad/Trans/Cofree.hs b/src/Control/Comonad/Trans/Cofree.hs
--- a/src/Control/Comonad/Trans/Cofree.hs
+++ b/src/Control/Comonad/Trans/Cofree.hs
@@ -6,6 +6,10 @@
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
 #include "free-common.h"
 
diff --git a/src/Control/Comonad/Trans/Coiter.hs b/src/Control/Comonad/Trans/Coiter.hs
--- a/src/Control/Comonad/Trans/Coiter.hs
+++ b/src/Control/Comonad/Trans/Coiter.hs
@@ -4,6 +4,10 @@
 {-# LANGUAGE MultiParamTypeClasses #-}
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
 #include "free-common.h"
 
diff --git a/src/Control/Monad/Free.hs b/src/Control/Monad/Free.hs
--- a/src/Control/Monad/Free.hs
+++ b/src/Control/Monad/Free.hs
@@ -7,8 +7,13 @@
 {-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE StandaloneDeriving #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
 #include "free-common.h"
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Control.Monad.Free
diff --git a/src/Control/Monad/Free/Ap.hs b/src/Control/Monad/Free/Ap.hs
--- a/src/Control/Monad/Free/Ap.hs
+++ b/src/Control/Monad/Free/Ap.hs
@@ -6,6 +6,10 @@
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
 #include "free-common.h"
 
diff --git a/src/Control/Monad/Free/Church.hs b/src/Control/Monad/Free/Church.hs
--- a/src/Control/Monad/Free/Church.hs
+++ b/src/Control/Monad/Free/Church.hs
@@ -4,6 +4,7 @@
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE UndecidableInstances #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE Safe #-}
 #include "free-common.h"
 
 -----------------------------------------------------------------------------
diff --git a/src/Control/Monad/Free/Class.hs b/src/Control/Monad/Free/Class.hs
--- a/src/Control/Monad/Free/Class.hs
+++ b/src/Control/Monad/Free/Class.hs
@@ -2,12 +2,14 @@
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE FunctionalDependencies #-}
 {-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE Safe #-}
 {-# LANGUAGE UndecidableInstances #-}
 #if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ >= 704
 {-# LANGUAGE DefaultSignatures #-}
 {-# LANGUAGE TypeFamilies #-}
 #endif
 {-# OPTIONS_GHC -fno-warn-deprecations #-}
+{-# LANGUAGE Safe #-}
 #include "free-common.h"
 
 -----------------------------------------------------------------------------
diff --git a/src/Control/Monad/Free/TH.hs b/src/Control/Monad/Free/TH.hs
--- a/src/Control/Monad/Free/TH.hs
+++ b/src/Control/Monad/Free/TH.hs
@@ -2,6 +2,11 @@
 #if __GLASGOW_HASKELL__ >= 800
 {-# OPTIONS_GHC -Wno-overlapping-patterns #-}
 #endif
+#if MIN_VERSION_template_haskell(2,12,0)
+{-# LANGUAGE Safe #-}
+#else
+{-# LANGUAGE Trustworthy #-}
+#endif
 #include "free-common.h"
 
 -----------------------------------------------------------------------------
diff --git a/src/Control/Monad/Trans/Free.hs b/src/Control/Monad/Trans/Free.hs
--- a/src/Control/Monad/Trans/Free.hs
+++ b/src/Control/Monad/Trans/Free.hs
@@ -7,6 +7,10 @@
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
 #include "free-common.h"
 
diff --git a/src/Control/Monad/Trans/Free/Ap.hs b/src/Control/Monad/Trans/Free/Ap.hs
--- a/src/Control/Monad/Trans/Free/Ap.hs
+++ b/src/Control/Monad/Trans/Free/Ap.hs
@@ -7,6 +7,10 @@
 #if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
 #endif
 #include "free-common.h"
 
diff --git a/src/Control/Monad/Trans/Free/Church.hs b/src/Control/Monad/Trans/Free/Church.hs
--- a/src/Control/Monad/Trans/Free/Church.hs
+++ b/src/Control/Monad/Trans/Free/Church.hs
@@ -2,6 +2,7 @@
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE Safe #-}
 {-# LANGUAGE UndecidableInstances #-}
 #include "free-common.h"
 
diff --git a/src/Control/Monad/Trans/Iter.hs b/src/Control/Monad/Trans/Iter.hs
--- a/src/Control/Monad/Trans/Iter.hs
+++ b/src/Control/Monad/Trans/Iter.hs
@@ -3,7 +3,13 @@
 {-# LANGUAGE UndecidableInstances #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE Rank2Types #-}
+#if __GLASGOW_HASKELL__ >= 707
 {-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE Safe #-}
+#else
+-- Manual Typeable instances
+{-# LANGUAGE Trustworthy #-}
+#endif
 #include "free-common.h"
 
 -----------------------------------------------------------------------------
diff --git a/src/Data/Functor/Classes/Compat.hs b/src/Data/Functor/Classes/Compat.hs
--- a/src/Data/Functor/Classes/Compat.hs
+++ b/src/Data/Functor/Classes/Compat.hs
@@ -1,5 +1,6 @@
 #include "free-common.h"
 #ifdef LIFTED_FUNCTOR_CLASSES
+{-# LANGUAGE Safe #-}
 module Data.Functor.Classes.Compat (
     mappend,
     module Data.Functor.Classes,
@@ -13,6 +14,7 @@
 #else
 {-# LANGUAGE DeriveTraversable #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE Trustworthy #-}
 module Data.Functor.Classes.Compat (
     Lift1 (..),
     on,