diff --git a/.ci/build_doxygen.sh b/.ci/build_doxygen.sh
deleted file mode 100644
index bd877d5..0000000
--- a/.ci/build_doxygen.sh
+++ /dev/null
@@ -1,25 +0,0 @@
-#!/bin/env sh
-# (Source me)
-
-set -evx
-
-#DOXYGEN_URL="http://doxygen.nl/files/doxygen-1.8.17.src.tar.gz"
-DOXYGEN_URL="https://github.com/doxygen/doxygen/archive/Release_1_8_15.tar.gz"
-cd "${DEPS_DIR}"
-
-if [[ ! -f "${DEPS_DIR}/doxygen/build/bin/doxygen" ]] ; then
-  echo "Downloading Doxygen"
-  mkdir -p doxygen
-  travis_retry wget --no-check-certificate --quiet -O - "${DOXYGEN_URL}" | tar --strip-components=1 -xz -C doxygen
-  cd doxygen
-  mkdir -p build
-  cd build
-  cmake ..
-  make -j2
-fi
-
-export PATH="${DEPS_DIR}/doxygen/build/bin:${PATH}"
-
-cd "${TRAVIS_BUILD_DIR}"
-
-set +evx
diff --git a/.ci/build_lcov.sh b/.ci/build_lcov.sh
deleted file mode 100644
index 7232e99..0000000
--- a/.ci/build_lcov.sh
+++ /dev/null
@@ -1,17 +0,0 @@
-#!/bin/env sh
-# (Source me)
-set -evx
-
-LCOV_URL="http://ftp.de.debian.org/debian/pool/main/l/lcov/lcov_1.13.orig.tar.gz"
-cd "${DEPS_DIR}"
-
-if [[ ! -f "${DEPS_DIR}/lcov/bin/lcov" ]] ; then
-  echo "Downloading lcov"
-  mkdir -p lcov
-  travis_retry wget --no-check-certificate --quiet -O - "${LCOV_URL}" | tar --strip-components=1 -xz -C lcov
-fi
-
-export PATH="${DEPS_DIR}/lcov/bin:${PATH}"
-cd "${TRAVIS_BUILD_DIR}"
-
-set +evx
diff --git a/.ci/make_and_test.sh b/.ci/make_and_test.sh
deleted file mode 100755
index a52c946..0000000
--- a/.ci/make_and_test.sh
+++ /dev/null
@@ -1,23 +0,0 @@
-#!/usr/bin/env bash
-echo -en "travis_fold:start:script.build\\r"
-echo "Building..."
-STD="$1"
-shift
-set -evx
-
-
-mkdir -p build
-cd build
-cmake .. -DCLI11_WARNINGS_AS_ERRORS=ON -DCLI11_SINGLE_FILE=ON -DCMAKE_CXX_STANDARD="$STD" -DCLI11_SINGLE_FILE_TESTS=ON -DCMAKE_BUILD_TYPE=Debug -DCMAKE_CXX_COMPILER_LAUNCHER=ccache $@
-cmake --build . -- -j2 --keep-going
-
-set +evx
-echo -en "travis_fold:end:script.build\\r"
-echo -en "travis_fold:start:script.test\\r"
-echo "Testing..."
-set -evx
-
-ctest --output-on-failure
-
-set +evx
-echo -en "travis_fold:end:script.test\\r"
diff --git a/.ci/run_codecov.sh b/.ci/run_codecov.sh
deleted file mode 100755
index fbc199c..0000000
--- a/.ci/run_codecov.sh
+++ /dev/null
@@ -1,27 +0,0 @@
-#!/usr/bin/env bash
-
-echo -en "travis_fold:start:script.build\\r"
-echo "Building..."
-set -evx
-
-cd "${TRAVIS_BUILD_DIR}"
-mkdir -p build
-cd build
-cmake .. -DCLI11_SINGLE_FILE_TESTS=OFF -DCLI11_EXAMPLES=OFF -DCMAKE_BUILD_TYPE=Coverage
-cmake --build . -- -j2
-cmake --build . --target CLI11_coverage
-
-set +evx
-echo -en "travis_fold:end:script.build\\r"
-echo -en "travis_fold:start:script.lcov\\r"
-echo "Capturing and uploading LCov..."
-set -evx
-
-lcov --directory . --capture --output-file coverage.info # capture coverage info
-lcov --remove coverage.info '*/tests/*' '*/examples/*' '*gtest*' '*gmock*' '/usr/*' --output-file coverage.info # filter out system
-lcov --list coverage.info #debug info
-# Uploading report to CodeCov
-bash <(curl -s https://codecov.io/bash) || echo "Codecov did not collect coverage reports"
-
-set +evx
-echo -en "travis_fold:end:script.lcov\\r"
diff --git a/.github/codecov.yml b/.github/codecov.yml
new file mode 100644
index 0000000..a0b0667
--- /dev/null
+++ b/.github/codecov.yml
@@ -0,0 +1,7 @@
+codecov:
+  notify:
+    after_n_builds: 4
+coverage:
+  status:
+    project:
+      informational: true
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index efb15d2..1226caa 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -6,7 +6,55 @@ on:
       - v*
   pull_request:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
+  coverage:
+    name: Coverage
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        std: ["11", "14", "17", "20"]
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Get LCov
+        run: |
+          wget https://github.com/linux-test-project/lcov/releases/download/v1.16/lcov-1.16.tar.gz
+          tar -xzf lcov-1.16.tar.gz
+          cd lcov-1.16
+          sudo make install
+
+      - name: Configure
+        run: |
+          cmake -S . -B build \
+            -DCMAKE_CXX_STANDARD=${{matrix.std}} \
+            -DCLI11_SINGLE_FILE_TESTS=OFF \
+            -DCLI11_EXAMPLES=OFF \
+            -DCMAKE_BUILD_TYPE=Coverage
+
+      - name: Build
+        run: cmake --build build -j4
+
+      - name: Test
+        run: cmake --build build --target CLI11_coverage
+
+      - name: Prepare coverage
+        run: |
+          lcov --directory . --capture --output-file coverage.info
+          lcov --remove coverage.info '*/tests/*' '*/examples/*' '/usr/*' --output-file coverage.info
+          lcov --list coverage.info
+        working-directory: build
+
+      - name: Upload coverage
+        run: |
+          curl -Os https://uploader.codecov.io/latest/linux/codecov
+          chmod +x codecov
+          ./codecov
+        working-directory: build
+
   clang-tidy:
     name: Clang-Tidy
     runs-on: ubuntu-latest
diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 11325d1..fd891ba 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -40,12 +40,12 @@ jobs:
           vmImage: "macOS-latest"
           cli11.std: 11
         Windows17:
-          vmImage: "vs2017-win2016"
+          vmImage: "windows-2019"
           cli11.std: 17
         Windows11:
-          vmImage: "vs2017-win2016"
+          vmImage: "windows-2019"
           cli11.std: 11
-        Windowslatest:
+        WindowsLatest:
           vmImage: "windows-2019"
           cli11.std: 20
           cli11.options: -DCMAKE_CXX_FLAGS="/std:c++latest /EHsc"
diff --git a/scripts/MakeSingleHeader.py b/scripts/MakeSingleHeader.py
index 6eaf749..4bc53dd 100755
--- a/scripts/MakeSingleHeader.py
+++ b/scripts/MakeSingleHeader.py
@@ -4,7 +4,7 @@ from __future__ import print_function, unicode_literals
 
 import os
 import re
-from argparse import ArgumentParser
+import argparse
 from subprocess import Popen, PIPE
 import warnings
 
@@ -128,8 +128,9 @@ def make_header(output, main_header, files, tag, namespace, macro=None, version=
 
 
 if __name__ == "__main__":
-    parser = ArgumentParser(
-        usage="Convert source to single header include. Can optionally add namespace and search-replace replacements (for macros)."
+    parser = argparse.ArgumentParser(
+        usage="Convert source to single header include. Can optionally add namespace and search-replace replacements (for macros).",
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
     )
     parser.add_argument("--output", default=None, help="Single header file output")
     parser.add_argument(
@@ -137,7 +138,7 @@ if __name__ == "__main__":
         default="CLI11.hpp.in",
         help="The main include file that defines the other files",
     )
-    parser.add_argument("files", nargs="*", help="The header files")
+    parser.add_argument("files", nargs="+", help="The header files")
     parser.add_argument("--namespace", default="CLI", help="Set the namespace")
     parser.add_argument("--tag", default="CLI11", help="Tag to look up")
     parser.add_argument(