diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5cbff92d..30b3934b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -7,30 +7,19 @@ env:
   SRC_DIR_PATH: desktop_version
 
 jobs:
-  build:
-    name: Build
+  build-mac:
+    name: Build (macos-latest)
 
-    runs-on: ${{ matrix.os }}
+    runs-on: macos-latest
 
     env:
       CXXFLAGS: -I/usr/local/include/SDL2
       LDFLAGS: -L/usr/local/lib
 
-    strategy:
-      matrix:
-        os: [ubuntu-18.04, macos-latest]
-
     steps:
     - uses: actions/checkout@v1
 
-    - name: Install dependencies (Linux)
-      if: startsWith(matrix.os, 'ubuntu')
-      run: |
-        sudo apt-get update
-        sudo apt-get install -y ninja-build libsdl2-dev libsdl2-mixer-dev
-
-    - name: Install dependencies (macOS)
-      if: startsWith(matrix.os, 'macos')
+    - name: Install dependencies
       run: brew install ninja sdl2 sdl2_mixer
 
     - name: CMake configure (default version)
@@ -69,6 +58,55 @@ jobs:
     - name: Build (no editor)
       run: ninja -C ${SRC_DIR_PATH}/build
 
+  build-lin:
+    name: Build (CentOS 7)
+
+    runs-on: ubuntu-latest
+    container: ghcr.io/leo60228/vvvvvv-build@sha256:485448ad437653d47ceb068a0f2b910f4eb336107d340a1f0d828ca95c987985
+
+    env:
+      CXXFLAGS: -I/usr/local/include/SDL2
+      LDFLAGS: -L/usr/local/lib
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: CMake configure (default version)
+      run: |
+        mkdir ${SRC_DIR_PATH}/build && cd ${SRC_DIR_PATH}/build
+        cmake ..
+    - name: Build (default version)
+      run: make -j $(nproc) -C ${SRC_DIR_PATH}/build
+
+    - name: CMake configure (official)
+      run: |
+        cd ${SRC_DIR_PATH}/build
+        cmake -DOFFICIAL_BUILD=ON ..
+    - name: Build (official)
+      run: |
+        make -j $(nproc) -C ${SRC_DIR_PATH}/build
+
+    - name: CMake configure (M&P)
+      run: |
+        cd ${SRC_DIR_PATH}/build
+        cmake -DOFFICIAL_BUILD=OFF -DMAKEANDPLAY=ON ..
+    - name: Build (M&P)
+      run: make -j $(nproc) -C ${SRC_DIR_PATH}/build
+
+    - name: CMake configure (no custom levels)
+      run: |
+        cd ${SRC_DIR_PATH}/build
+        cmake -DMAKEANDPLAY=OFF -DCUSTOM_LEVEL_SUPPORT=DISABLED ..
+    - name: Build (no custom levels)
+      run: make -j $(nproc) -C ${SRC_DIR_PATH}/build
+
+    - name: CMake configure (no editor)
+      run: |
+        cd ${SRC_DIR_PATH}/build
+        cmake -DCUSTOM_LEVEL_SUPPORT=NO_EDITOR ..
+    - name: Build (no editor)
+      run: make -j $(nproc) -C ${SRC_DIR_PATH}/build
+
   build-win:
     name: Build (windows-latest)
 
diff --git a/desktop_version/.dockerignore b/desktop_version/.dockerignore
new file mode 100644
index 00000000..4d9b1a27
--- /dev/null
+++ b/desktop_version/.dockerignore
@@ -0,0 +1,2 @@
+**
+!Dockerfile
diff --git a/desktop_version/Dockerfile b/desktop_version/Dockerfile
new file mode 100644
index 00000000..7f033991
--- /dev/null
+++ b/desktop_version/Dockerfile
@@ -0,0 +1,41 @@
+FROM centos:7
+
+# run first to improve caching (other things update more often than SDL2)
+WORKDIR /tmp
+RUN curl -O https://www.libsdl.org/release/SDL2-2.0.14.tar.gz
+RUN tar -xf SDL2-2.0.14.tar.gz
+RUN mkdir SDL2-2.0.14/build
+RUN curl -O https://www.libsdl.org/projects/SDL_mixer/release/SDL2_mixer-2.0.4.tar.gz
+RUN tar -xf SDL2_mixer-2.0.4.tar.gz
+RUN mkdir SDL2_mixer-2.0.4/build
+
+# add EPEL (for SDL2)
+RUN yum -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
+
+# install dependencies
+RUN yum -y install \
+    # used below
+    yum-utils \
+    # SDL2_mixer dependencies
+    libogg-devel libvorbis-devel \
+    # VVVVVV dependencies
+    gcc-c++ cmake make
+
+RUN yum-builddep -y SDL2
+
+RUN yum clean all
+
+WORKDIR /tmp/SDL2-2.0.14/build
+RUN ../configure
+RUN make -j $(nproc)
+RUN make install
+
+WORKDIR /tmp/SDL2_mixer-2.0.4/build
+RUN ../configure
+RUN make -j $(nproc)
+RUN make install
+
+WORKDIR /tmp
+RUN rm -rf SDL2-2.0.14.tar.gz SDL2-2.0.14/ SDL2_mixer-2.0.4.tar.gz SDL2_mixer-2.0.4/
+
+WORKDIR /