diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 00000000..2e614077
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,144 @@
+name: CI
+
+on: [ push, pull_request, workflow_dispatch ]
+
+jobs:
+  CI:
+    name: ${{ matrix.name }}
+    runs-on: ${{ matrix.os }}
+    continue-on-error: ${{ contains(matrix.os, 'macos') }}
+    strategy:
+      fail-fast: false
+      matrix:
+        name: [ "Linux x64 (Ubuntu 20.04) - GCC 10" ]
+        os: [ ubuntu-20.04 ]
+        sanitize: [ false ]
+        build:
+          - { cc: gcc, cxx: g++, linker: ld }
+        include:
+          - name: "Linux x64 (Ubuntu 20.04) - Clang 10 with ASan and UBSan"
+            os: ubuntu-20.04
+            sanitize: true
+            build: { cc: clang-10, cxx: clang++-10, linker: ld.lld-10 }
+          - name: "macOS (10.15) - Xcode 12.3"
+            os: macos-10.15
+            sanitize: false
+            build: { cc: clang, cxx: clang++, linker: ld.lld }
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Update apt
+        if: contains(matrix.os, 'ubuntu')
+        env:
+          DEBIAN_FRONTEND: noninteractive
+        run: sudo -E apt-get update -qq -o Acquire::Retries=3
+
+      - name: Add libheif PPA
+        if: contains(matrix.os, 'ubuntu')
+        run: |
+          sudo add-apt-repository ppa:strukturag/libde265
+          sudo add-apt-repository ppa:strukturag/libheif
+
+      - name: Install Ubuntu dependencies
+        if: contains(matrix.os, 'ubuntu')
+        env:
+          DEBIAN_FRONTEND: noninteractive
+        run:
+          sudo -E apt-get install --fix-missing -qq -o Acquire::Retries=3
+            gtk-doc-tools gobject-introspection
+            python3-pip python3-setuptools python3-wheel
+            libfftw3-dev libexif-dev libjpeg-turbo8-dev
+            libpng-dev libwebp-dev libtiff5-dev
+            libheif-dev libexpat1-dev libcfitsio-dev
+            libmatio-dev libnifti-dev liborc-0.4-dev
+            liblcms2-dev libpoppler-glib-dev librsvg2-dev
+            libgif-dev libopenexr-dev libpango1.0-dev
+            libgsf-1-dev libopenslide-dev libffi-dev
+
+      - name: Install macOS dependencies
+        if: contains(matrix.os, 'macos')
+        run:
+          brew install
+            autoconf automake libtool
+            gtk-doc gobject-introspection
+            cfitsio fftw giflib
+            glib libexif libgsf
+            libheif libjpeg-turbo libmatio
+            librsvg libspng libtiff
+            little-cms2 openexr openslide
+            orc pango poppler webp
+
+      - name: Install Clang 10
+        env:
+          DEBIAN_FRONTEND: noninteractive
+        if: contains(matrix.os, 'ubuntu') && matrix.build.cc == 'clang-10'
+        run:
+          sudo -E apt-get install --fix-missing -qq -o Acquire::Retries=3
+            clang-10 libomp-10-dev lld-10 llvm-10
+
+      - name: Prepare build environment
+        run: |
+          echo "CC=${{ matrix.build.cc }}" >> $GITHUB_ENV
+          echo "CXX=${{ matrix.build.cxx }}" >> $GITHUB_ENV
+          echo "LD=${{ matrix.build.linker }}" >> $GITHUB_ENV
+          echo "CPPFLAGS=-Wall" >> $GITHUB_ENV
+
+      - name: Prepare Ubuntu environment
+        if: contains(matrix.os, 'ubuntu')
+        run: echo "JOBS=$(nproc)" >> $GITHUB_ENV
+
+      - name: Prepare macOS environment
+        if: contains(matrix.os, 'macos')
+        run: |
+          echo "JOBS=$(sysctl -n hw.logicalcpu)" >> $GITHUB_ENV
+          echo "PKG_CONFIG_PATH=/usr/local/opt/jpeg-turbo/lib/pkgconfig:/usr/local/opt/libxml2/lib/pkgconfig" >> $GITHUB_ENV
+
+      - name: Prepare sanitizers
+        if: matrix.sanitize
+        env:
+          LLVM_PREFIX: /usr/lib/llvm-10
+        run: |
+          ASAN_DSO=`$CC -print-file-name=libclang_rt.asan-x86_64.so`
+          echo "LDSHARED=$CC -shared" >> $GITHUB_ENV
+          echo "CPPFLAGS=-g -fsanitize=address,undefined -fno-omit-frame-pointer -fopenmp -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION" >> $GITHUB_ENV
+          echo "LDFLAGS=-g -fsanitize=address,undefined -shared-libasan -fopenmp=libomp" >> $GITHUB_ENV
+          echo "ASAN_DSO=$ASAN_DSO" >> $GITHUB_ENV
+          echo "ASAN_OPTIONS=suppressions=${{ github.workspace }}/suppressions/asan.supp" >> $GITHUB_ENV
+          echo "LSAN_OPTIONS=suppressions=${{ github.workspace }}/suppressions/lsan.supp" >> $GITHUB_ENV
+          echo "UBSAN_OPTIONS=suppressions=${{ github.workspace }}/suppressions/ubsan.supp:print_stacktrace=1" >> $GITHUB_ENV
+          echo "LD_LIBRARY_PATH=$LLVM_PREFIX/lib:`dirname $ASAN_DSO`" >> $GITHUB_ENV
+          echo "$LLVM_PREFIX/bin" >> $GITHUB_PATH
+          # workaround for https://github.com/google/sanitizers/issues/89
+          # otherwise libIlmImf-2_3.so ends up as <unknown module>
+          echo "DLCLOSE_PRELOAD=${{ github.workspace }}/dlclose.so" >> $GITHUB_ENV
+          echo -e '#include <stdio.h>\nint dlclose(void*handle){return 0;}' | $CC -shared -xc -odlclose.so -
+
+      - name: Configure libvips
+        run:
+          ./autogen.sh
+            --disable-dependency-tracking
+            --disable-deprecated || (cat config.log && exit 1)
+
+      - name: Build libvips
+        run: make V=0 -j$JOBS
+
+      - name: Check libvips
+        run: make V=0 check
+
+      - name: Install libvips
+        run: sudo make V=0 install
+
+      - name: Rebuild the shared library cache
+        if: contains(matrix.os, 'ubuntu')
+        run: sudo ldconfig
+
+      - name: Install pyvips
+        run: pip3 install pyvips[test]
+
+      - name: Run test suite
+        env:
+          VIPS_LEAK: 1
+          LD_PRELOAD: ${{ env.ASAN_DSO }} ${{ env.DLCLOSE_PRELOAD }}
+        run: python3 -m pytest -sv --log-cli-level=WARNING test/test-suite
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
deleted file mode 100644
index 89843490..00000000
--- a/.github/workflows/test.yml
+++ /dev/null
@@ -1,84 +0,0 @@
-name: Test
-
-# to-do:
-#   - add a macos test with brew etc.
-#   - build with clang/asan/etc. and run the fuzz tests
-
-on:
-  - push
-  - pull_request
-  - workflow_dispatch # manually triggered workflow
-
-jobs:
-  build:
-    runs-on: ubuntu-20.04
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v2
-
-      - name: Update apt
-        env:
-          DEBIAN_FRONTEND: noninteractive
-        run:
-          sudo apt-get update -qq -o Acquire::Retries=3
-
-      - name: Add libheif PPA
-        run: |
-          sudo add-apt-repository ppa:strukturag/libde265
-          sudo add-apt-repository ppa:strukturag/libheif
-
-      - name: Install platform dependencies
-        env:
-          DEBIAN_FRONTEND: noninteractive
-        run:
-          sudo apt-get install --fix-missing -qq -o Acquire::Retries=3
-                gtk-doc-tools
-                gobject-introspection
-                python3-pip
-                python3-setuptools
-                python3-wheel
-                libfftw3-dev
-                libexif-dev
-                libjpeg-turbo8-dev
-                libpng-dev
-                libwebp-dev
-                libtiff5-dev
-                libheif-dev
-                libexpat1-dev
-                libcfitsio-dev
-                libgsl-dev
-                libmatio-dev
-                libnifti-dev
-                liborc-0.4-dev
-                liblcms2-dev
-                libpoppler-glib-dev
-                librsvg2-dev
-                libgif-dev
-                libopenexr-dev
-                libpango1.0-dev
-                libgsf-1-dev
-                libopenslide-dev
-                libffi-dev
-
-      - name: Configure libvips
-        run: CFLAGS=-Wall CXXFLAGS=-Wall ./autogen.sh
-            --disable-dependency-tracking
-            --disable-deprecated
-
-      - name: Build libvips
-        run: make V=0 -j$(nproc)
-
-      - name: Check libvips
-        run: make V=0 check
-
-      - name: Install libvips
-        run: |
-          sudo make V=0 install
-          sudo ldconfig
-
-      - name: Install pyvips
-        run: pip3 install pyvips pytest
-
-      - name: Run test suite
-        run: VIPS_LEAK=1 python3 -m pytest
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index bebdeff5..00000000
--- a/.travis.yml
+++ /dev/null
@@ -1,163 +0,0 @@
-language: cpp
-
-env:
-  global:
-    - PYTHON=python3
-    - PYVIPS_VERSION=master
-
-addons:
-  apt:
-    update: true
-    sources: &common_sources
-      # add support for AVIF files
-      - sourceline: 'ppa:strukturag/libheif'
-      - sourceline: 'ppa:strukturag/libde265'
-    packages: &common_packages
-      - gtk-doc-tools
-      - gobject-introspection
-      - python3-pip
-      - python3-setuptools
-      - python3-wheel
-      - libfftw3-dev
-      - libexif-dev
-      - libjpeg-turbo8-dev
-      - libpng-dev
-      - libwebp-dev
-      - libtiff5-dev
-      - libheif-dev
-      - libexpat1-dev
-      - libcfitsio-dev
-      - libgsl-dev
-      - libmatio-dev
-      - libnifti-dev
-      - liborc-0.4-dev
-      - liblcms2-dev
-      - libpoppler-glib-dev
-      - librsvg2-dev
-      - libgif-dev
-      - libopenexr-dev
-      - libpango1.0-dev
-      - libgsf-1-dev
-      - libopenslide-dev
-      - libffi-dev
-  homebrew:
-    update: true
-    packages:
-      - ccache
-      - cfitsio
-      - fftw
-      - giflib
-      - glib
-      - gobject-introspection
-      - gtk-doc
-      - libexif
-      - libgsf
-      - libheif
-      - libjpeg-turbo
-      - libmatio
-      - librsvg
-      - libspng
-      - libtiff
-      - little-cms2
-      - openexr
-      - openslide
-      - orc
-      - pango
-      - poppler
-      - webp
-
-jobs:
-  allow_failures:
-    - os: osx
-  fast_finish: true
-  include:
-    - os: linux
-      dist: bionic
-      compiler: gcc
-      name: "Linux x64 (Ubuntu 18.04) - GCC 10"
-      addons:
-        apt:
-          sources:
-            - *common_sources
-            - ubuntu-toolchain-r-test
-          packages:
-            - *common_packages
-            - libmagick++-dev
-            - g++-10
-      env:
-        - JPEG=/usr
-        - JOBS=`nproc`
-        - WITH_MAGICK=yes
-        - CC="gcc-10"
-        - CXX="g++-10"
-        - LDSHARED="$CC -shared"
-        - CFLAGS="-Wcast-function-type"
-      cache: ccache
-    - os: linux
-      dist: bionic
-      compiler: clang
-      name: "Linux x64 (Ubuntu 18.04) - Clang 10 with ASan and UBSan"
-      addons:
-        apt:
-          sources:
-            - *common_sources
-            - sourceline: deb https://apt.llvm.org/bionic/ llvm-toolchain-bionic-10 main
-              key_url: https://apt.llvm.org/llvm-snapshot.gpg.key
-          packages:
-            - *common_packages
-            - clang-10
-            - libomp-10-dev
-      env:
-        - JPEG=/usr
-        - JOBS=`nproc`
-        - WITH_MAGICK=no
-        - CC="clang-10"
-        - CXX="clang++-10"
-        - LDSHARED="$CC -shared"
-        - CFLAGS="-fsanitize=address,undefined -fno-omit-frame-pointer -fopenmp -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION"
-        - CXXFLAGS="$CFLAGS"
-        - LDFLAGS="-fsanitize=address,undefined -shared-libasan -fopenmp=libomp"
-        - ASAN_DSO=`$CC -print-file-name=libclang_rt.asan-x86_64.so`
-        - ASAN_SYMBOLIZER_PATH=`which llvm-symbolizer-10`
-        - ASAN_OPTIONS="suppressions=$TRAVIS_BUILD_DIR/suppressions/asan.supp"
-        - LSAN_OPTIONS="suppressions=$TRAVIS_BUILD_DIR/suppressions/lsan.supp"
-        - UBSAN_OPTIONS="suppressions=$TRAVIS_BUILD_DIR/suppressions/ubsan.supp:print_stacktrace=1"
-        - LD_LIBRARY_PATH="/usr/lib/llvm-10/lib:`dirname $ASAN_DSO`"
-        - DLCLOSE_PRELOAD="$TRAVIS_BUILD_DIR/dlclose.so"
-      before_script:
-        # workaround for https://github.com/google/sanitizers/issues/89
-        # otherwise libIlmImf-2_2.so ends up as <unknown module>
-        - echo -e '#include <stdio.h>\nint dlclose(void*handle){return 0;}' | $CC -shared -xc -odlclose.so -
-      cache: ccache
-    - os: osx
-      osx_image: xcode11
-      name: "macOS (10.14.6) - Xcode 11"
-      env:
-        - JPEG=/usr/local/opt/jpeg-turbo
-        - JOBS="`sysctl -n hw.ncpu`"
-        - WITH_MAGICK=no
-        - PATH="/usr/local/opt/ccache/libexec:$PATH"
-        - PKG_CONFIG_PATH="/usr/local/opt/jpeg-turbo/lib/pkgconfig:/usr/local/opt/libxml2/lib/pkgconfig:$PKG_CONFIG_PATH"
-        - HOMEBREW_NO_AUTO_UPDATE=1
-        - CC="clang"
-        - CXX="clang++"
-      cache: ccache
-
-install:
-  - $PYTHON -m pip download --no-deps https://github.com/libvips/pyvips/archive/$PYVIPS_VERSION.tar.gz
-  - tar xf $PYVIPS_VERSION.tar.gz
-  - $PYTHON -m pip install --user --upgrade pyvips-$PYVIPS_VERSION/[test]
-  - ./autogen.sh
-    --disable-dependency-tracking
-    --disable-deprecated
-    --with-jpeg-includes=$JPEG/include
-    --with-jpeg-libraries=$JPEG/lib
-    --with-magick=$WITH_MAGICK
-  - make -j$JOBS -s
-
-script:
-  - make -j$JOBS -s -k V=0 VERBOSE=1 check
-  - LD_LIBRARY_PATH="$PWD/libvips/.libs:$LD_LIBRARY_PATH"
-    DYLD_LIBRARY_PATH=$PWD/libvips/.libs
-    LD_PRELOAD="$ASAN_DSO $DLCLOSE_PRELOAD"
-    $PYTHON -m pytest -sv --log-cli-level=WARNING test/test-suite
diff --git a/README.md b/README.md
index 80d2bbaa..8d362ff7 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # libvips : an image processing library
 
-[![Test](https://github.com/libvips/libvips/workflows/Test/badge.svg)](https://github.com/libvips/libvips/actions?query=workflow%3ATest)
+[![CI](https://github.com/libvips/libvips/workflows/CI/badge.svg)](https://github.com/libvips/libvips/actions)
 [![Fuzzing Status](https://oss-fuzz-build-logs.storage.googleapis.com/badges/libvips.svg)](https://bugs.chromium.org/p/oss-fuzz/issues/list?sort=-opened&can=2&q=proj:libvips)
 [![Coverity Status](https://scan.coverity.com/projects/6503/badge.svg)](https://scan.coverity.com/projects/jcupitt-libvips)
 [![Gitter](https://badges.gitter.im/libvips/devchat.svg)](https://gitter.im/libvips/devchat?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)
diff --git a/suppressions/lsan.supp b/suppressions/lsan.supp
index ec44e871..47d8282e 100644
--- a/suppressions/lsan.supp
+++ b/suppressions/lsan.supp
@@ -3,5 +3,6 @@ leak:python3
 leak:bash
 leak:libfontconfig.so
 leak:libglib-2.0.so
-leak:libIlmImf-2_2.so
+leak:libIlmImf-2_3.so
+leak:libIlmThread-2_3.so
 leak:libstdc++.so