diff --git a/.github/workflows/mapbase_build-base.yml b/.github/workflows/mapbase_build-base.yml
index d7892f49721..4c3196300e9 100644
--- a/.github/workflows/mapbase_build-base.yml
+++ b/.github/workflows/mapbase_build-base.yml
@@ -53,19 +53,19 @@ jobs:
     runs-on: windows-latest
 
     steps:
-    - uses: actions/checkout@v4
-    - uses: actions/setup-python@v5
+    - uses: actions/checkout@v7
+    - uses: actions/setup-python@v7
       with:
         python-version: '3.13'
 
     - name: Add MSBuild to PATH
-      uses: compnerd/gha-setup-vsdevenv@v6
+      uses: compnerd/gha-setup-vsdevenv@v7
 
       # HACKHACK: MSBuild doesn't seem to recognize Python even when its directory is within PATH,
       # so we currently have to make it call Python directly.
       # This assumes %Python3_ROOT_DIR% will always be set by setup-python above.
     - name: Implement Python workaround
-      if: inputs.project-group == 'game' || inputs.project-group == 'everything'
+      if: contains(inputs.project-group, 'game') || contains(inputs.project-group, 'everything')
       working-directory: 'src/game/server'
       shell: bash
       run: |
@@ -76,7 +76,7 @@ jobs:
       working-directory: 'src'
       shell: cmd
       run: |
-        devtools\bin\vpc.exe /${{inputs.game}} /win${{inputs.arch}} /define:SOURCESDK +${{inputs.project-group}} /mksln build.sln
+        devtools\bin\vpc.exe /${{inputs.game}} /win${{inputs.arch}} /define:SOURCESDK /define:CI_RUNNER +${{inputs.project-group}} /mksln build.sln
 
       # --------------------------------------------------------------------
 
@@ -91,7 +91,7 @@ jobs:
       # --------------------------------------------------------------------
 
     - name: Publish binaries
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v7
       with:
         name: '${{inputs.project-group}}_win${{inputs.arch}}_${{ inputs.configuration }}'
         path: |
@@ -101,17 +101,19 @@ jobs:
           game/mod_*/x64/bin
           !game/bin/x64/steam_api64.dll
           !game/bin/linux64/libsteam_api.so
+          game/*.exe
+          game/*.exe
         if-no-files-found: error
 
   build_ubuntu:
-    if: inputs.build-linux == true && inputs.project-group != 'maptools' # No Linux map tools for now
+    if: inputs.build-linux == true
     name: Linux
     runs-on: ubuntu-latest
     env:
       config: ${{ inputs.configuration }}
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v7
 
     - name: Install dependencies
       run: |
@@ -119,12 +121,11 @@ jobs:
         sudo apt-get -y install podman python3
 
     - name: Pick game
-      if: inputs.project-group == 'game' || inputs.project-group == 'shaders'
       working-directory: 'src'
       shell: bash
       run: |
         sed -i 's|/hl2mp /tf|/${{inputs.game}}|' buildgameprojects
-        sed -i 's|+game|+${{inputs.project-group}}|' buildgameprojects
+        sed -i 's|+game|/define:CI_RUNNER +${{inputs.project-group}}|' buildgameprojects
         sed -i 's|/linux64|/linux${{inputs.arch}}|' buildgameprojects
 
     - name: Set configuration
@@ -155,7 +156,7 @@ jobs:
     # For now, don't publish the .dbg files even though we publish .pdb files on Windows
     # (they're too big)
     - name: Publish binaries
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v7
       with:
         name: '${{inputs.project-group}}_linux${{inputs.arch}}_${{ inputs.configuration }}'
         path: |
@@ -168,4 +169,6 @@ jobs:
           !game/mod_*/bin/linux64/*_srv.so
           !game/mod_*/bin/*_srv.so
           !game/bin/linux64/libsteam_api.so
+          game/*
+          game/*
         if-no-files-found: error
diff --git a/.github/workflows/mapbase_build-games-x86.yml b/.github/workflows/mapbase_build-games-x86.yml
deleted file mode 100644
index 2a66fd46e0e..00000000000
--- a/.github/workflows/mapbase_build-games-x86.yml
+++ /dev/null
@@ -1,44 +0,0 @@
-#
-# MAPBASE SOURCE 2013 CI
-#
-# Builds game projects every time a pull request which modifies the game code is opened.
-# If you're using a fork of Mapbase, feel free to configure this to meet your repository's needs.
-#
-# See mapbase_build-base.yml for more information on how this works.
-
-name: Build Game [SP]
-
-on:
-  pull_request:
-    branches:
-      - develop
-      - mapbase-mp-2025
-    paths:
-      - '.github/workflows/mapbase_build-base.yml'
-      - '.github/workflows/mapbase_build-games.yml'
-      - 'src/vpc_scripts/**'
-      - 'src/game/**'
-      - '!src/game/server/tf/**'
-      - '!src/game/client/tf/**'
-      - '!src/game/shared/tf/**'
-      - '!src/game/server/hl2mp/**'
-      - '!src/game/client/hl2mp/**'
-      - '!src/game/shared/hl2mp/**'
-      - 'src/mathlib/**'
-      - 'src/responserules/runtime/**'
-      - 'src/tier1/**'
-      - 'src/vgui2/vgui_controls/**'
-      - 'src/vscript/**'
-
-jobs:
-  games:
-    strategy:
-      matrix:
-        configuration: [Release, Debug]
-    uses: ./.github/workflows/mapbase_build-base.yml
-    with:
-      configuration: ${{ matrix.configuration }}
-      game: 'hl2 /episodic' # Change this if your mod is not using these game projects
-      project-group: 'game'
-      build-linux: true # Disable this if you don't want to compile for Linux
-      arch: '32'
diff --git a/.github/workflows/mapbase_build-games.yml b/.github/workflows/mapbase_build-games.yml
deleted file mode 100644
index cdc880a5e84..00000000000
--- a/.github/workflows/mapbase_build-games.yml
+++ /dev/null
@@ -1,44 +0,0 @@
-#
-# MAPBASE SOURCE 2013 CI
-#
-# Builds game projects every time a pull request which modifies the game code is opened.
-# If you're using a fork of Mapbase, feel free to configure this to meet your repository's needs.
-#
-# See mapbase_build-base.yml for more information on how this works.
-
-name: Build Game [MP]
-
-on:
-  pull_request:
-    branches:
-      - develop
-      - mapbase-mp-2025
-    paths:
-      - '.github/workflows/mapbase_build-base.yml'
-      - '.github/workflows/mapbase_build-games.yml'
-      - 'src/vpc_scripts/**'
-      - 'src/game/**'
-      - '!src/game/server/hl2/**'
-      - '!src/game/client/hl2/**'
-      - '!src/game/shared/hl2/**'
-      - '!src/game/server/episodic/**'
-      - '!src/game/client/episodic/**'
-      - '!src/game/shared/episodic/**'
-      - 'src/mathlib/**'
-      - 'src/responserules/runtime/**'
-      - 'src/tier1/**'
-      - 'src/vgui2/vgui_controls/**'
-      - 'src/vscript/**'
-
-jobs:
-  games:
-    strategy:
-      matrix:
-        configuration: [Release, Debug]
-    uses: ./.github/workflows/mapbase_build-base.yml
-    with:
-      configuration: ${{ matrix.configuration }}
-      game: 'tf /hl2mp' # Change this if your mod is not using these game projects
-      project-group: 'game'
-      build-linux: true # Disable this if you don't want to compile for Linux
-      arch: '64'
diff --git a/.github/workflows/mapbase_build-generic.yml b/.github/workflows/mapbase_build-generic.yml
new file mode 100644
index 00000000000..1868cd1dda0
--- /dev/null
+++ b/.github/workflows/mapbase_build-generic.yml
@@ -0,0 +1,96 @@
+#
+# MAPBASE SOURCE 2013 CI
+#
+# Builds projects every time a pull request which modifies the code is opened.
+# If you're using a fork of Mapbase, feel free to configure this to meet your repository's needs.
+#
+# See mapbase_build-base.yml for more information on how this works.
+
+name: Build Projects
+
+on:
+  pull_request:
+    branches:
+      - develop
+      - mapbase-mp-2025
+      - feature/combined-sp-mp
+    paths:
+      - '.github/workflows/mapbase_build-generic.yml'
+      - 'src/**'
+
+jobs:
+  check-changes:
+    runs-on: ubuntu-latest
+    outputs:
+      project-groups: ${{ steps.combine-group.outputs.groups }}
+    steps:
+      - uses: actions/checkout@v7
+
+      - name: Identify file changes
+        uses: dorny/paths-filter@v4
+        id: filter
+        with:
+          filters: |
+            games:
+              - 'src/game/**'
+              - 'src/responserules/runtime/**'
+              - 'src/vgui2/vgui_controls/**'
+              - 'src/vscript/**'
+            shaders:
+              - 'src/materialsystem/**'
+            maptools:
+              - 'src/utils/vbsp/**'
+              - 'src/utils/vvis/**'
+              - 'src/utils/vvis_launcher/**'
+              - 'src/utils/vrad/**'
+              - 'src/utils/vrad_launcher/**'
+              - 'src/vscript/**'
+            everything:
+              - 'src/vpc_scripts/**'
+              - 'src/mathlib/**'
+              - 'src/tier1/**'
+              - '.github/workflows/mapbase_build-generic.yml'
+
+      - name: Combine project groups
+        id: combine-group
+        env:
+          in_games_group: ${{ steps.filter.outputs.games }}
+          in_shaders_group: ${{ steps.filter.outputs.shaders }}
+          in_maptools_group: ${{ steps.filter.outputs.maptools }}
+          in_everything_group: ${{ steps.filter.outputs.everything }}
+        run: |
+          all_groups=""
+          if [ "$in_everything_group" = "true" ]; then
+            # 'everything' encompasses all other groups
+            all_groups+=" +everything"
+          else
+            if [ "$in_games_group" = "true" ]; then
+              all_groups+=" +game"
+            fi
+            if [ "$in_shaders_group" = "true" ]; then
+              all_groups+=" +shaders"
+            fi
+            if [ "$in_maptools_group" = "true" ]; then
+              all_groups+=" +maptools"
+            fi
+          fi
+          echo "groups=${all_groups:2}" >> "$GITHUB_OUTPUT"
+
+  build:
+    needs: check-changes
+    strategy:
+      matrix:
+        arch: [32, 64]
+        configuration: [Release, Debug]
+        include:
+          - game: 'tf /hl2mp'
+            arch: 64
+          - game: 'hl2 /episodic'
+            arch: 32
+    uses: ./.github/workflows/mapbase_build-base.yml
+    with:
+      configuration: ${{ matrix.configuration }}
+      game: ${{ matrix.game }}
+      project-group: ${{ needs.check-changes.outputs.project-groups }}
+      build-linux: true # Disable this if you don't want to compile for Linux
+      arch: ${{ matrix.arch }}
diff --git a/.github/workflows/mapbase_build-maptools.yml b/.github/workflows/mapbase_build-maptools.yml
deleted file mode 100644
index 7cf3da92697..00000000000
--- a/.github/workflows/mapbase_build-maptools.yml
+++ /dev/null
@@ -1,39 +0,0 @@
-#
-# MAPBASE SOURCE 2013 CI
-#
-# Builds map tool projects every time a pull request which modifies the map tool code is opened.
-# If you're using a fork of Mapbase, feel free to configure this to meet your repository's needs.
-#
-# See mapbase_build-base.yml for more information on how this works.
-
-name: Build Map Tools
-
-on:
-  pull_request:
-    branches:
-      - develop
-      - mapbase-mp-2025
-    paths:
-      - '.github/workflows/mapbase_build-maptools.yml'
-      - 'src/vpc_scripts/**'
-      - 'src/utils/vbsp/**'
-      - 'src/utils/vvis/**'
-      - 'src/utils/vvis_launcher/**'
-      - 'src/utils/vrad/**'
-      - 'src/utils/vrad_launcher/**'
-      - 'src/mathlib/**'
-      - 'src/tier1/**'
-      - 'src/vgui2/vgui_controls/**'
-      - 'src/vscript/**'
-
-jobs:
-  maptools:
-    strategy:
-      matrix:
-        configuration: [Release, Debug]
-        arch: [32, 64]
-    uses: ./.github/workflows/mapbase_build-base.yml
-    with:
-      configuration: ${{ matrix.configuration }}
-      project-group: 'maptools'
-      arch: ${{ matrix.arch }}
diff --git a/.github/workflows/mapbase_build-shaders.yml b/.github/workflows/mapbase_build-shaders.yml
deleted file mode 100644
index a023369dd43..00000000000
--- a/.github/workflows/mapbase_build-shaders.yml
+++ /dev/null
@@ -1,39 +0,0 @@
-#
-# MAPBASE SOURCE 2013 CI
-#
-# Builds shader projects every time a pull request which modifies the shader code is opened.
-# If you're using a fork of Mapbase, feel free to configure this to meet your repository's needs.
-#
-# See mapbase_build-base.yml for more information on how this works.
-
-name: Build Shaders
-
-on:
-  pull_request:
-    branches:
-      - develop
-      - mapbase-mp-2025
-    paths:
-      - '.github/workflows/mapbase_build-shaders.yml'
-      - 'src/vpc_scripts/**'
-      - 'src/materialsystem/**'
-      - 'src/mathlib/**'
-
-jobs:
-  shaders:
-    strategy:
-      matrix:
-        configuration: [Release, Debug]
-        arch: [32, 64]
-        include:
-          - game: 'episodic' # Should be switched to 'tf /hl2mp' once we figure out what's wrong with the MP projects
-            arch: 64
-          - game: 'episodic'
-            arch: 32
-    uses: ./.github/workflows/mapbase_build-base.yml
-    with:
-      configuration: ${{ matrix.configuration }}
-      game: ${{ matrix.game }}
-      project-group: 'shaders'
-      build-linux: true # Disable this if you don't want to compile for Linux
-      arch: ${{ matrix.arch }}
diff --git a/src/materialsystem/stdshaders/stdshader_dx9_inc.vpc b/src/materialsystem/stdshaders/stdshader_dx9_inc.vpc
index f80b39347e2..d645d90f59d 100644
--- a/src/materialsystem/stdshaders/stdshader_dx9_inc.vpc
+++ b/src/materialsystem/stdshaders/stdshader_dx9_inc.vpc
@@ -16,8 +16,10 @@ $Configuration	"Debug"
 {
 	$General
 	{
-		$OutputDirectory		"Debug_dx9" [$WINDOWS]
-		$IntermediateDirectory	"Debug_dx9" [$WINDOWS]
+		// Causes problems when building multiple shader projects in parallel.
+		// It'd be nice to automate dependency, but for now, just fall back to game-based naming
+		$OutputDirectory		"Debug_dx9" [$WINDOWS&&!$MAPBASE]
+		$IntermediateDirectory	"Debug_dx9" [$WINDOWS&&!$MAPBASE]
 	}
 }
 
@@ -25,8 +27,8 @@ $Configuration	"Release"
 {
 	$General
 	{
-		$OutputDirectory		"Release_dx9" [$WINDOWS]
-		$IntermediateDirectory	"Release_dx9" [$WINDOWS]
+		$OutputDirectory		"Release_dx9" [$WINDOWS&&!$MAPBASE]
+		$IntermediateDirectory	"Release_dx9" [$WINDOWS&&!$MAPBASE]
 	}
 }
 
diff --git a/src/vpc_scripts/projects.vgc b/src/vpc_scripts/projects.vgc
index 0b172bfe735..a360c2a91ea 100644
--- a/src/vpc_scripts/projects.vgc
+++ b/src/vpc_scripts/projects.vgc
@@ -92,7 +92,7 @@ $Project "motionmapper"
 
 $Project "phonemeextractor"
 {
-	"utils\phonemeextractor\phonemeextractor.vpc" [$WIN32]
+	"utils\phonemeextractor\phonemeextractor.vpc" [$WIN32&&!$CI_RUNNER]
 }
 
 $Project "raytrace"