diff --git a/.github/scripts/install_deps.sh b/.github/scripts/install_deps.sh
index bad4c9a4..9e572ae6 100755
--- a/.github/scripts/install_deps.sh
+++ b/.github/scripts/install_deps.sh
@@ -2,7 +2,7 @@
 # This script requires `sh` instead of `bash` because the latter is not always installed on FreeBSD.
 set -eu
 
-case "${1%-*}" in
+case "${1%%-*}" in
 	ubuntu|debian)
 		sudo apt-get -qq update
 		sudo apt-get install -yq bison libpng-dev pkgconf
@@ -14,7 +14,8 @@ case "${1%-*}" in
 		brew install bison md5sha1sum make
 		# Export `bison` to allow using the version we install from Homebrew,
 		# instead of the outdated one preinstalled on macOS (which doesn't even support `-Wall`...)
-		export PATH="/opt/homebrew/opt/bison/bin:$PATH"
+		# This path  ↓ is used on Intel macOS, and this one ↓ on ARM ones.
+		export PATH="/usr/local/opt/bison/bin:/opt/homebrew/opt/bison/bin:$PATH"
 		printf 'PATH=%s\n' "$PATH" >>"$GITHUB_ENV" # Make it available to later CI steps too
 		;;
 	freebsd)
@@ -27,7 +28,8 @@ case "${1%-*}" in
 		bison() { win_bison "$@"; } # An alias doesn't work, so we use a function instead.
 		;;
 	*)
-		echo "::error:: Cannot install deps for OS '$1'"
+		echo "Cannot install deps for OS '$1'"
+		exit 1
 		;;
 esac
 
diff --git a/.github/workflows/create-release-artifacts.yml b/.github/workflows/create-release-artifacts.yml
index 4e17714c..6a07e83e 100644
--- a/.github/workflows/create-release-artifacts.yml
+++ b/.github/workflows/create-release-artifacts.yml
@@ -51,7 +51,7 @@ jobs:
           if-no-files-found: error
 
   macos:
-    runs-on: macos-14
+    runs-on: macos-26
     steps:
       - name: Checkout repo
         uses: actions/checkout@v6
diff --git a/.github/workflows/testing.yml b/.github/workflows/testing.yml
index c78f51e7..3712812e 100644
--- a/.github/workflows/testing.yml
+++ b/.github/workflows/testing.yml
@@ -36,11 +36,12 @@ jobs:
   unix:
     strategy:
       matrix:
-        os: [ubuntu-22.04, macos-14]
+        os: [ubuntu-22.04, macos-15-intel, macos-26]
         cxx: [g++, clang++]
         buildsys: [make, cmake]
-        exclude:
-          - { os: macos-14, cxx: g++ } # Don't use `g++` on macOS; it's just an alias to `clang++`.
+        exclude: # Don't use `g++` on macOS; it's just an alias to `clang++`.
+          - { os: macos-15-intel, cxx: g++ }
+          - { os: macos-26, cxx: g++ }
       fail-fast: false
     runs-on: ${{ matrix.os }}
     steps:
@@ -106,7 +107,7 @@ jobs:
           ctest --test-dir build --schedule-random
 
   macos-static:
-    runs-on: macos-14
+    runs-on: macos-26
     steps:
       - name: Checkout repo
         uses: actions/checkout@v6
@@ -145,7 +146,7 @@ jobs:
         uses: actions/cache@v5
         with:
           path: ${{ fromJSON(steps.test-deps-cache-params.outputs.paths) }}
-          key: macos-14-${{ steps.test-deps-cache-params.outputs.hash }}
+          key: macos-26-${{ steps.test-deps-cache-params.outputs.hash }}
       - name: Fetch test dependency repositories
         if: steps.test-deps-cache.outputs.cache-hit != 'true'
         continue-on-error: true
diff --git a/test/fetch-test-deps.sh b/test/fetch-test-deps.sh
index cc3e0f49..e2718634 100755
--- a/test/fetch-test-deps.sh
+++ b/test/fetch-test-deps.sh
@@ -58,7 +58,7 @@ case "$actionname" in
 		action() { # _ _ repo _
 			# libbet depends on PIL to build
 			if [ "$3" = "libbet" ]; then
-				case "${osname%-*}" in
+				case "${osname%%-*}" in
 					ubuntu | debian)
 						sudo apt-get install python3-pil
 						;;