diff --git a/.github/workflows/win32.yml b/.github/workflows/win32.yml
deleted file mode 100644
index 809c00a..0000000
--- a/.github/workflows/win32.yml
+++ /dev/null
@@ -1,59 +0,0 @@
-name: Testbuild for Win32
-run-name: testbuild_win32
-on:
-  push:
-    branches:
-      - 'master'
-  pull_request:
-    types:
-      - edited
-      - opened
-      - synchronize
-concurrency:
-  # Cancel concurrent workflows for the same PR or commit hash.
-  group: ${{github.workflow}}-${{github.event_name == 'pull_request' && github.head_ref || github.sha}}
-  cancel-in-progress: true
-jobs:
-  build_mingw_x86_32:
-    runs-on: windows-latest
-    permissions:
-      actions: read
-      contents: read
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          - { sys: mingw32, env: i686 }
-    steps:
-    - uses: msys2/setup-msys2@v2
-      with:
-        msystem: ${{matrix.sys}}
-        update: true
-        install: >-
-          git
-          make
-          mingw-w64-${{matrix.env}}-gcc
-          mingw-w64-${{matrix.env}}-make
-    - name: Check out repository code
-      uses: actions/checkout@v7
-    - name: Build
-      shell: msys2 {0}
-      run: |
-        # Public runners come with 4 CPUs.
-        make -j4
-    - name: Create testbuild package
-      shell: msys2 {0}
-      run: |
-        # Create release directory tree
-        mkdir -p publish/quake2-ctf-win32-${{github.sha}}/misc/docs
-        # Copy release assets
-        cp -r release/* publish/quake2-ctf-win32-${{github.sha}}/
-        # Copy misc assets
-        cp LICENSE publish/quake2-ctf-win32-${{github.sha}}/misc/docs/LICENSE.txt
-        cp README.md publish/quake2-ctf-win32-${{github.sha}}/misc/docs/README.txt
-    - name: Upload testbuild package
-      uses: actions/upload-artifact@v7
-      with:
-        name: quake2-ctf-win32-${{github.sha}}
-        path: publish/
-        if-no-files-found: error
diff --git a/.github/workflows/win64.yml b/.github/workflows/win64.yml
deleted file mode 100644
index 7821e08..0000000
--- a/.github/workflows/win64.yml
+++ /dev/null
@@ -1,61 +0,0 @@
-name: Testbuild for Win64
-run-name: testbuild_win64
-on:
-  push:
-    branches:
-      - 'master'
-  pull_request:
-    types:
-      - edited
-      - opened
-      - synchronize
-concurrency:
-  # Cancel concurrent workflows for the same PR or commit hash.
-  group: ${{github.workflow}}-${{github.event_name == 'pull_request' && github.head_ref || github.sha}}
-  cancel-in-progress: true
-jobs:
-  build_mingw_x86_64:
-    runs-on: windows-latest
-    permissions:
-      actions: read
-      contents: read
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          - { sys: mingw64, env: x86_64 }
-    env:
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-    steps:
-    - uses: msys2/setup-msys2@v2
-      with:
-        msystem: ${{matrix.sys}}
-        update: true
-        install: >-
-          git
-          make
-          mingw-w64-${{matrix.env}}-gcc
-          mingw-w64-${{matrix.env}}-make
-    - name: Check out repository code
-      uses: actions/checkout@v7
-    - name: Build
-      shell: msys2 {0}
-      run: |
-        # Public runners come with 4 CPUs.
-        make -j4
-    - name: Create testbuild package
-      shell: msys2 {0}
-      run: |
-        # Create release directory tree
-        mkdir -p publish/quake2-ctf-win64-${{github.sha}}/misc/docs
-        # Copy release assets
-        cp -r release/* publish/quake2-ctf-win64-${{github.sha}}/
-        # Copy misc assets
-        cp LICENSE publish/quake2-ctf-win64-${{github.sha}}/misc/docs/LICENSE.txt
-        cp README.md publish/quake2-ctf-win64-${{github.sha}}/misc/docs/README.txt
-    - name: Upload testbuild package
-      uses: actions/upload-artifact@v7
-      with:
-        name: quake2-ctf-win64-${{github.sha}}
-        path: publish/
-        if-no-files-found: error
diff --git a/.github/workflows/win_mingw.yml b/.github/workflows/win_mingw.yml
new file mode 100644
index 0000000..1727a23
--- /dev/null
+++ b/.github/workflows/win_mingw.yml
@@ -0,0 +1,65 @@
+name: Testbuild for x86 and x86_64 Windows with MinGW
+on:
+  push:
+    branches:
+      - 'master'
+  pull_request:
+    types:
+      - edited
+      - opened
+      - synchronize
+concurrency:
+  # Cancel concurrent workflows for the same PR or commit hash.
+  group: ${{github.workflow}}-${{github.event_name == 'pull_request' && github.head_ref || github.sha}}
+  cancel-in-progress: true
+jobs:
+  build:
+    runs-on: windows-latest
+    permissions:
+      actions: read
+      contents: read
+    strategy:
+      fail-fast: false
+      # Abuse the build matrix to hack around inconsistent naming.
+      matrix:
+        include:
+          - arch: x86
+            family: i686
+            winapi: win32
+          - arch: x64
+            family: x86_64
+            winapi: win64
+    name: win_buildenv_${{matrix.winapi}}
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v7
+      - name: Setup build environment
+        shell: bash
+        run: |
+          curl -o makebuildenv.sh https://raw.githubusercontent.com/yquake2/yquake2/refs/heads/master/stuff/winbuild/makebuildenv.sh
+          chmod +x makebuildenv.sh
+          ./makebuildenv.sh buildenv
+          echo "${GITHUB_WORKSPACE}/buildenv/w64devkit-${{matrix.arch}}/bin/" >> ${GITHUB_PATH}
+      - name: Build
+        shell: sh -l {0}
+        run: |
+          cd ${GITHUB_WORKSPACE}
+          # Public runners come with 4 CPUs.
+          make -j4
+      - name: Create testbuild package
+        shell: bash
+        run: |
+          # Create release directory tree
+          mkdir -p publish/quake2-ctf-${{matrix.winapi}}-${{github.sha}}/misc/docs
+          # Copy release assets
+          cp -r release/* publish/quake2-ctf-${{matrix.winapi}}-${{github.sha}}/
+          # Copy misc assets
+          cp CHANGELOG publish/quake2-ctf-${{matrix.winapi}}-${{github.sha}}/misc/docs/CHANGELOG.txt
+          cp LICENSE publish/quake2-ctf-${{matrix.winapi}}-${{github.sha}}/misc/docs/LICENSE.txt
+          cp README.md publish/quake2-ctf-${{matrix.winapi}}-${{github.sha}}/misc/docs/README.txt
+      - name: Upload testbuild package
+        uses: actions/upload-artifact@v7
+        with:
+          name: quake2-ctf-${{matrix.winapi}}-${{github.sha}}
+          path: publish/
+          if-no-files-found: error
diff --git a/Makefile b/Makefile
index b3b1426..84c2211 100755
--- a/Makefile
+++ b/Makefile
@@ -58,6 +58,8 @@ ifeq ($(wildcard $(CONFIG_FILE)), $(CONFIG_FILE))
 include $(CONFIG_FILE)
 endif
 
+# ----------
+
 # Normalize QUIET value to either "x" or ""
 ifdef QUIET
 	override QUIET := "x"
@@ -65,17 +67,10 @@ else
 	override QUIET := ""
 endif
 
-# Detect the OS
-ifdef SystemRoot
-YQ2_OSTYPE ?= Windows
-else
-YQ2_OSTYPE ?= $(shell uname -s)
-endif
+# ----------
 
-# Special case for MinGW
-ifneq (,$(findstring MINGW,$(YQ2_OSTYPE)))
-YQ2_OSTYPE := Windows
-endif
+# Detect the OS, normalize some abiguous YQ2_OSTYPE strings.
+YQ2_OSTYPE ?= $(shell uname -s | sed -e 's/MINGW.*/Windows/' -e 's/Windows.*/Windows/')
 
 # Detect the architecture
 ifeq ($(YQ2_OSTYPE), Windows)
@@ -86,28 +81,17 @@ else # i686-w64-mingw32
 YQ2_ARCH ?= i386
 endif
 else # windows, but MINGW_CHOST not defined
-ifdef PROCESSOR_ARCHITEW6432
-# 64 bit Windows
-YQ2_ARCH ?= $(PROCESSOR_ARCHITEW6432)
-else
-# 32 bit Windows
-YQ2_ARCH ?= $(PROCESSOR_ARCHITECTURE)
-endif
+YQ2_ARCH ?= $(shell uname -m | sed -e 's/i.86/i386/')
 endif # windows but MINGW_CHOST not defined
 else
 ifneq ($(YQ2_OSTYPE), Darwin)
 # Normalize some abiguous YQ2_ARCH strings
-YQ2_ARCH ?= $(shell uname -m | sed -e 's/i.86/i386/' -e 's/amd64/x86_64/' -e 's/^arm.*/arm/')
+YQ2_ARCH ?= $(shell uname -m | sed -e 's/i.86/i386/' -e 's/amd64/x86_64/' -e 's/arm64/aarch64/' -e 's/^arm.*/arm/')
 else
 YQ2_ARCH ?= $(shell uname -m)
 endif
 endif
 
-# On Windows / MinGW $(CC) is undefined by default.
-ifeq ($(YQ2_OSTYPE),Windows)
-CC ?= gcc
-endif
-
 # Detect the compiler
 ifeq ($(shell $(CC) -v 2>&1 | grep -c "clang version"), 1)
 COMPILER := clang