diff --git a/.ci/report-coverage.sh b/.ci/report-coverage.sh
new file mode 100755
index 00000000000..4e6ec06b257
--- /dev/null
+++ b/.ci/report-coverage.sh
@@ -0,0 +1,10 @@
+#!/bin/sh
+
+set -ex
+
+# Set --connect-timeout to work around https://github.com/curl/curl/issues/4461
+curl -S -L --connect-timeout 5 --retry 6 -s -o /tmp/codecov.sh https://codecov.io/bash
+
+for _ in 1 2 3 4 5; do
+  bash /tmp/codecov.sh -Z -X fix -f coverage.xml "$@" && break
+done
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
new file mode 100644
index 00000000000..4ae0877cd67
--- /dev/null
+++ b/.github/workflows/main.yml
@@ -0,0 +1,202 @@
+name: main
+
+on:
+  push:
+    branches:
+      - my-4.6-maintenance
+      - "[0-9]+.[0-9]+.x"
+    tags:
+      - "*"
+  pull_request:
+
+jobs:
+  tests:
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+        name: [
+          "ubuntu-py39",
+          "ubuntu-py38",
+          "ubuntu-py38 (pexpect, integration)",
+          "ubuntu-pypy3",
+
+          "macos-py36",
+
+          "windows-py37 (1)",
+          "windows-py37 (2)",
+
+          "xdist",
+
+          "linting",
+          "docs",
+          "doctesting",
+          "mypy",
+        ]
+
+        include:
+          - name: "ubuntu-py39"
+            python: "3.9"
+            os: ubuntu-latest
+            tox_env: "py39-coverage"
+          - name: "ubuntu-py38"
+            python: "3.8"
+            os: ubuntu-latest
+            tox_env: "py38-numpy-oldattrs-twisted-coverage"
+          - name: "ubuntu-pypy3"
+            python: "pypy3"
+            os: ubuntu-latest
+            tox_env: "pypy3-coverage"
+            pytest_addopts: "-m 'pypy_specific or acceptance_tests'"
+          - name: "ubuntu-py38 (pexpect, integration)"
+            python: "3.8"
+            os: ubuntu-latest
+            # NOTE: the lsof factor is not really useful currently, with its
+            # warnings being ignored.  This uses it here only to cover the
+            # LsofFdLeakChecker itself.
+            # (https://github.com/blueyed/pytest/issues/195)
+            tox_env: "py38-lsof-pexpect-coverage"
+            pytest_addopts: "-m 'uses_pexpect or integration'"
+            script_prefix: "env -u COLUMNS"
+
+          # Coverage for:
+          # - osx
+          # - pygments
+          # - verbosity=1
+          - name: "macos-py36"
+            python: "3.6"
+            os: macos-latest
+            tox_env: "py36-pygments-coverage"
+            pytest_addopts: "--verbosity=1"
+
+          - name: "windows-py37 (1)"
+            python: "3.7"
+            os: windows-latest
+            tox_env: "py37-coverage-grouped"
+            # Coverage for:
+            # - verbosity=2
+            pytest_addopts: "--verbosity=2 --test-group-count 2 --test-group=1"
+          - name: "windows-py37 (2)"
+            python: "3.7"
+            os: windows-latest
+            tox_env: "py37-coverage-grouped"
+            # Coverage for:
+            # - verbosity=2
+            pytest_addopts: "--verbosity=2 --test-group-count 2 --test-group=2"
+
+          - name: "xdist"
+            python: "3.8"
+            os: ubuntu-latest
+            tox_env: "py38-xdist-coverage"
+            pytest_addopts: "-m 'xdist_specific or acceptance_tests' -n 0"
+
+          - name: "linting"
+            python: "3.8"
+            os: ubuntu-latest
+            tox_env: "linting_ci"
+          - name: "docs"
+            python: "3.8"
+            os: ubuntu-latest
+            tox_env: "docs"
+          - name: "doctesting"
+            python: "3.8"
+            os: ubuntu-latest
+            tox_env: "doctesting-coverage"
+          - name: "mypy"
+            python: "3.8"
+            os: ubuntu-latest
+            tox_env: "mypy_ci"
+
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        fetch-depth: 2000
+    - run: git fetch --tags origin
+    - name: Set up Python ${{ matrix.python }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python }}
+
+    # Caching.
+    - name: set PY_CACHE_KEY
+      run: echo "PY_CACHE_KEY=$(python -c 'import hashlib, sys;print(hashlib.sha256(sys.version.encode()+sys.executable.encode()).hexdigest())')" >> $GITHUB_ENV
+    - name: Cache .tox
+      if: (matrix.tox_env != 'docs')
+      uses: actions/cache@v1
+      with:
+        path: ${{ github.workspace }}/.tox/${{ matrix.tox_env }}
+        key: "tox|${{ matrix.tox_env }}|${{ env.PY_CACHE_KEY }}|${{ hashFiles('tox.ini', 'setup.*') }}"
+    - name: Cache .tox (docs)
+      if: (matrix.tox_env == 'docs')
+      uses: actions/cache@v1
+      with:
+        path: ${{ github.workspace }}/.tox/${{ matrix.tox_env }}
+        # Work around tox not rebuilding on changed requirements file (https://github.com/tox-dev/tox/issues/149).
+        key: "tox|${{ matrix.tox_env }}|${{ env.PY_CACHE_KEY }}|${{ hashFiles('tox.ini', 'setup.*', 'doc/en/requirements.txt') }}"
+    - name: Cache .pre-commit
+      if: (matrix.tox_env == 'linting_ci')
+      uses: actions/cache@v1
+      with:
+        path: ~/.cache/pre-commit
+        key: pre-commit|${{ env.PY_CACHE_KEY }}|${{ hashFiles('.pre-commit-config.yaml') }}
+
+    - name: Install tox / version information
+      env:
+        PIP_DISABLE_PIP_VERSION_CHECK: "1"
+      run: |
+        python -m pip --version
+        python -m pip install git+https://github.com/blueyed/tox@master
+        python -m pip list
+
+    - name: Setup tox environment
+      id: setup_tox
+      run: python -m tox --notest -v --durations -e ${{ matrix.tox_env }}
+
+    - name: Test
+      env:
+        PYTEST_ADDOPTS: "-ra --durations=50 ${{ matrix.pytest_addopts }}"
+        COLUMNS: "120"
+        # UTF-8 mode for Windows (https://docs.python.org/3/using/windows.html#utf-8-mode).
+        PYTHONUTF8: "1"
+        TOX_TESTENV_PASSENV: "PYTHONUTF8"
+      run: "${{ matrix.script_prefix }} tox -e ${{ matrix.tox_env }}"
+
+    - name: Report coverage
+      if: always() && (contains(matrix.tox_env, '-coverage') && (steps.setup_tox.outcome == 'success'))
+      env:
+        CODECOV_TOKEN: d79f3a85-e675-4d75-8f55-3d0e4a99ebe8
+      run: "bash .ci/report-coverage.sh -n '${{ matrix.name }}' -F 'GHA,${{ runner.os }}'"
+
+  deploy:
+    if: github.event_name == 'push' && startsWith(github.event.ref, 'refs/tags') && github.repository == 'pytest-dev/pytest'
+    runs-on: ubuntu-latest
+    needs: [tests]
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        fetch-depth: 2000
+    - run: git fetch --tags origin
+    - name: Set up Python
+      uses: actions/setup-python@v2
+      with:
+        python-version: "3.7"
+    - name: Install dependencies
+      run: |
+        python -m pip --version
+        python -m pip install wheel setuptools git+https://github.com/blueyed/tox@master
+    - name: Build package
+      run: |
+        python setup.py sdist bdist_wheel
+    - name: Publish package to PyPI
+      uses: pypa/gh-action-pypi-publish@master
+      with:
+        user: __token__
+        password: ${{ secrets.pypi_token }}
+    - name: Publish GitHub release notes
+      env:
+        GH_RELEASE_NOTES_TOKEN: ${{ secrets.release_notes }}
+      run: |
+        sudo apt-get install pandoc
+        tox -e publish-gh-release-notes
+
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index b8d73a5e020..00000000000
--- a/.travis.yml
+++ /dev/null
@@ -1,80 +0,0 @@
-language: python
-dist: xenial
-python: '3.7.4'
-cache: false
-
-env:
-  global:
-    - PYTEST_ADDOPTS="-vv --showlocals --durations=100 --exitfirst"
-    - PYTEST_COVERAGE=1
-    - TOX=git+https://github.com/blueyed/tox@master
-    - TOX_EXTRA_ARGS=--durations
-
-# setuptools-scm needs all tags in order to obtain a proper version
-git:
-  depth: false
-
-install:
-  - python -m pip install $TOX
-
-jobs:
-  include:
-    # Coverage for:
-    # - TestArgComplete (linux only)
-    # - numpy
-    # - verbose=0
-    # - test_sys_breakpoint_interception (via pexpect).
-    - stage: baseline
-      env: TOXENV=py38-xdist
-      python: '3.8'
-
-    - env: TOXENV=py27-xdist
-      python: '2.7'
-
-    - stage: tests
-      env: TOXENV=py37-numpy-pexpect-twisted
-      python: '3.7.4'
-
-    - env: TOXENV=py36-xdist PYTEST_REORDER_TESTS=0
-      python: '3.6.9'
-
-    - env: TOXENV=py35-xdist
-      python: '3.5.9'
-
-    - env:
-        - TOXENV=py34-xdist
-        - TOX='tox==3.14.0'  # tox 3.14.1 dropped support for py34.
-        - TOX_EXTRA_ARGS=  # no --durations.
-      python: '3.4'
-
-    - env: TOXENV=linting,docs,doctesting
-      cache:
-        directories:
-          - $HOME/.cache/pre-commit
-
-before_script:
-  - |
-    # Do not (re-)upload coverage with cron runs.
-    if [[ "$TRAVIS_EVENT_TYPE" = cron ]]; then
-      PYTEST_COVERAGE=0
-    fi
-  - |
-    if [[ "$PYTEST_COVERAGE" = 1 ]]; then
-      export COVERAGE_FILE="$PWD/.coverage"
-      export COVERAGE_PROCESS_START="$PWD/.coveragerc"
-      export _PYTEST_TOX_COVERAGE_RUN="coverage run -m"
-      export _PYTEST_TOX_EXTRA_DEP=coverage-enable-subprocess
-    fi
-  - python -m tox --notest -v $TOX_EXTRA_ARGS
-
-script: env COLUMNS=120 python -m tox -v $TOX_EXTRA_ARGS
-
-after_success:
-  - |
-    if [[ "$PYTEST_COVERAGE" = 1 ]]; then
-      env CODECOV_NAME="$TOXENV-$TRAVIS_OS_NAME" scripts/report-coverage.sh
-    fi
-
-branches:
-  only:
-    - my-4.6-maintenance
diff --git a/tox.ini b/tox.ini
index 1c838ff5b02..0ff94f9c99d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,7 +2,6 @@
 isolated_build = True
 minversion = 3.5.3
 distshare = {homedir}/.tox/distshare
-# make sure to update environment list in travis.yml and appveyor.yml
 envlist =
     linting
     py27
@@ -11,6 +10,7 @@ envlist =
     py36
     py37
     py38
+    py39
     pypy
     pypy3
     {py27,py37}-{pexpect,xdist,twisted,numpy,pluggymaster}
@@ -22,39 +22,43 @@ envlist =
 [testenv]
 commands =
     {env:_PYTEST_TOX_COVERAGE_RUN:} pytest {posargs:{env:_PYTEST_TOX_DEFAULT_POSARGS:}}
+    doctesting: {env:_PYTEST_TOX_COVERAGE_RUN:} pytest --doctest-modules --pyargs _pytest
     coverage: coverage combine
-    coverage: coverage report
-passenv = USER USERNAME COVERAGE_* TRAVIS PYTEST_ADDOPTS
+    coverage: coverage report -m
+    coverage: coverage xml
+ignore_errors = true
+passenv = USER USERNAME COVERAGE_* PYTEST_ADDOPTS PYTEST_REORDER_TESTS TERM COLUMNS
+    coverage: CODECOV_* CI CI_* GITHUB_* TRAVIS TRAVIS_*
 setenv =
-    _PYTEST_TOX_DEFAULT_POSARGS={env:_PYTEST_TOX_POSARGS_LSOF:} {env:_PYTEST_TOX_POSARGS_PEXPECT:} {env:_PYTEST_TOX_POSARGS_TWISTED:} {env:_PYTEST_TOX_POSARGS_XDIST:}
+    _PYTEST_TOX_DEFAULT_POSARGS={env:_PYTEST_TOX_POSARGS_DOCTESTING:} {env:_PYTEST_TOX_POSARGS_LSOF:}
 
-    # Configuration to run with coverage similar to Travis/Appveyor, e.g.
+    # Configuration to run with coverage similar to CI, e.g.
     # "tox -e py37-coverage".
     coverage: _PYTEST_TOX_COVERAGE_RUN=coverage run -m
     coverage: _PYTEST_TOX_EXTRA_DEP=coverage-enable-subprocess
     coverage: COVERAGE_FILE={toxinidir}/.coverage
     coverage: COVERAGE_PROCESS_START={toxinidir}/.coveragerc
 
+    doctesting: _PYTEST_TOX_POSARGS_DOCTESTING=doc/en
+    grouped: PYTEST_REORDER_TESTS={env:PYTEST_REORDER_TESTS:0}
     nobyte: PYTHONDONTWRITEBYTECODE=1
-
     lsof: _PYTEST_TOX_POSARGS_LSOF=--lsof
-
-    pexpect: _PYTEST_TOX_PLATFORM=linux|darwin
-    pexpect: _PYTEST_TOX_POSARGS_PEXPECT=-m uses_pexpect
-
-    twisted: _PYTEST_TOX_POSARGS_TWISTED=testing/test_unittest.py
-
-    xdist: _PYTEST_TOX_POSARGS_XDIST=-n auto
+    oldattrs: _PYTEST_TOX_TWISTED=twisted<20.3.0
+    xdist: PYTEST_ADDOPTS=-n auto {env:PYTEST_ADDOPTS:}
 extras = testing
 deps =
+    doctesting: PyYAML
+    grouped: pytest-test-groups
+    oldattrs: attrs==17.4.0
     numpy: numpy
     pexpect: pexpect
     pluggymaster: git+https://github.com/pytest-dev/pluggy.git@master
-    twisted: twisted
-    twisted: unittest2
-    xdist: pytest-xdist>=1.13,<2
+    pygments: pygments
+    twisted: {env:_PYTEST_TOX_TWISTED:twisted}
+    xdist: pytest-xdist>=1.13
     {env:_PYTEST_TOX_EXTRA_DEP:}
-platform = {env:_PYTEST_TOX_PLATFORM:.*}
+    # Pin pylib for Windows (pending investigation of test failures).
+    py>=1.5.0,!=1.8.2,<1.9.0 ; sys_platform == 'win32'
 
 [testenv:py27-subprocess]
 deps =
@@ -69,7 +73,37 @@ commands =
 skip_install = True
 basepython = python3
 deps = pre-commit>=1.11.0
-commands = pre-commit run --all-files --show-diff-on-failure
+commands = pre-commit run --all-files --show-diff-on-failure {posargs:}
+
+# Special env to massage pre-commit config for CI:
+#  - removes mypy config from there, which gets run (more precise) via
+#    separate mypy env.
+#  - removes black config: fine if you want to use it via pre-commit/manually,
+#    but does not need to be enforced (slow, issues).
+[testenv:linting_ci]
+skip_install = True
+basepython = python3
+deps = {[testenv:linting]deps}
+whitelist_externals = sh
+ignore_errors = false
+commands =
+  sh -c "sed -e '/^-   repo: .*mirrors-mypy/,/^ \+args:/ d'  -e '/^-   repo: .*black$/,/^ \+args:/ d' .pre-commit-config.yaml > {envtmpdir}/pc.yaml"
+  pre-commit run --all-files --show-diff-on-failure --config {envtmpdir}/pc.yaml {posargs:}
+
+[testenv:mypy]
+deps =
+extras = checkqa-mypy, testing
+commands = mypy {posargs:src testing}
+
+# Checks default (configured) python_version, and the minimal one.
+[testenv:mypy_ci]
+deps = {[testenv:mypy]deps}
+extras = {[testenv:mypy]extras}
+whitelist_externals = sh
+commands =
+  mypy {posargs:src testing}
+  mypy --python-version 3.5 --warn-unused-ignores {posargs:src testing}
+  sh scripts/check-mypy-pyi.sh
 
 [testenv:docs]
 basepython = python3
@@ -116,9 +150,9 @@ commands =
 
 [testenv:py37-freeze]
 changedir = testing/freeze
-# Disable PEP 517 with pip, which does not work with PyInstaller currently.
 deps =
     pyinstaller
+ignore_errors = false
 commands =
     {envpython} create_executable.py
     {envpython} tox_run.py