diff --git a/.github/workflows/precommit.yml b/.github/workflows/precommit.yml
index 859dcd34c..4c4818a39 100644
--- a/.github/workflows/precommit.yml
+++ b/.github/workflows/precommit.yml
@@ -13,18 +13,17 @@ on:
 
 jobs:
   build-and-test:
-    name: Build and test ${{matrix.cfg.name}} ${{matrix.os.name}}
+    name: Build and test ${{matrix.cfg.name}}
 
-    runs-on: ${{matrix.os.id}}
+    runs-on: ${{matrix.cfg.os}}
 
     strategy:
       matrix:
-        os:
-          - { name: 'Linux', id: 'ubuntu-20.04' }
         cfg:
-          - { name: 'GCC', cc: gcc-10, cxx: g++-10, config: --copt=-Wno-maybe-uninitialized }
-          - { name: 'LLVM+libstdc++', cc: clang, cxx: clang++, config: --copt=-Wno-uninitialized }
-          - { name: 'LLVM+libc++', cc: clang, cxx: clang++, config: --config=libc++ --copt=-Wno-uninitialized }
+          - { name: 'Linux GCC', os: 'ubuntu-20.04', cc: gcc-10, cxx: g++-10, config: --copt=-Wno-maybe-uninitialized }
+          - { name: 'Linux LLVM+libstdc++', os: 'ubuntu-20.04', cc: clang, cxx: clang++, config: --copt=-Wno-uninitialized }
+          - { name: 'Linux LLVM+libc++', os: 'ubuntu-20.04', cc: clang, cxx: clang++, config: --config=libc++ --copt=-Wno-uninitialized }
+          - { name: 'MacOS LLVM+libc++', os: 'macos-10.15', config: --config=libc++ --copt=-Wno-uninitialized }
 
     env:
       CC:  ${{matrix.cfg.cc}}
@@ -32,16 +31,26 @@ jobs:
 
     steps:
       - uses: actions/checkout@v2
-      - name: install infrastructure
+      - name: install infrastructure (Linux)
+        if: matrix.cfg.os == 'ubuntu-20.04'
         run: |
           sudo apt-get update
           sudo apt-get install gettext python2-dev python3-dev libsdl2-dev libosmesa6-dev python-numpy-dev python3-numpy-dev python-pil python3-pil python-enum34
           sudo find /usr -type f -name Python.h -o -name arrayobject.h -o -name functional -o -name -filesystem
           sudo ln -s /usr/lib/llvm-10/include/c++/v1 /usr/include/c++/v1
-      - name: build
+      - name: install infrastructure (MacOS)
+        if: matrix.cfg.os == 'macos-10.15'
+        run: |
+          brew install SDL2
+          sudo -H pip install numpy
+          sudo -H pip3 install numpy
+          sudo find -L /usr /Library -type f -name SDL.h -o -name glib.h -o -name Python.h -o -name arrayobject.h
+      - name: build (Linux)
+        if: matrix.cfg.os == 'ubuntu-20.04'
         run: |
           bazel --bazelrc=.precommit.bazelrc build ${{matrix.cfg.config}} --copt=-Wno-sign-compare //...
-      - name: run-tests
+      - name: run-tests (Linux)
+        if: matrix.cfg.os == 'ubuntu-20.04'
         timeout-minutes: 45
         run: |
           bazel --bazelrc=.precommit.bazelrc test  ${{matrix.cfg.config}} --copt=-Wno-sign-compare //...
@@ -49,6 +58,12 @@ jobs:
           bazel --bazelrc=.precommit.bazelrc test  ${{matrix.cfg.config}} --copt=-Wno-sign-compare //python/tests:python_module_test.py3 --test_tag_filters="" --test_arg=--verbose
           bazel --bazelrc=.precommit.bazelrc test  ${{matrix.cfg.config}} --copt=-Wno-sign-compare //python/tests:dmenv_module_test.py2 --test_tag_filters="" --test_arg=--verbose
           bazel --bazelrc=.precommit.bazelrc test  ${{matrix.cfg.config}} --copt=-Wno-sign-compare //python/tests:dmenv_module_test.py3 --test_tag_filters="" --test_arg=--verbose
-      - name: run-agent
+      - name: run-agent (Linux)
+        if: matrix.cfg.os == 'ubuntu-20.04'
         run: |
           bazel --bazelrc=.precommit.bazelrc run   ${{matrix.cfg.config}} --copt=-Wno-sign-compare --define headless=osmesa //:python_random_agent
+      - name: build-and-run-tests (MacOS)
+        if: matrix.cfg.os == 'macos-10.15'
+        timeout-minutes: 45
+        run: |
+          bazel --bazelrc=.precommit.bazelrc build ${{matrix.cfg.config}} --copt=-Wno-sign-compare -c opt --dynamic_mode=off --show_progress_rate_limit=10 //:game_lib_headless_macos
diff --git a/BUILD b/BUILD
index 195c6572d..75f602249 100644
--- a/BUILD
+++ b/BUILD
@@ -827,6 +827,27 @@ cc_library(
     alwayslink = 1,
 )
 
+cc_library(
+    name = "game_lib_headless_macos",
+    srcs = IOQ3_COMMON_SRCS + [
+        CODE_DIR + "/deepmind/dmlab_connect.c",
+        CODE_DIR + "/null/null_input.c",
+        CODE_DIR + "/null/null_snddma.c",
+
+        ## OpenGL rendering
+        CODE_DIR + "/deepmind/headless_macos_glimp.c",
+        CODE_DIR + "/deepmind/glimp_common.h",
+        CODE_DIR + "/deepmind/glimp_common.c",
+    ],
+    hdrs = ["public/dmlab.h"],
+    copts = IOQ3_COMMON_COPTS,
+    defines = IOQ3_COMMON_DEFINES,
+    linkopts = ["-framework OpenGL"],
+    tags = ["manual"],  # don't build on Linux with //...
+    deps = IOQ3_COMMON_DEPS,
+    alwayslink = 1,
+)
+
 cc_library(
     name = "game_lib_headless_osmesa",
     srcs = IOQ3_COMMON_SRCS + [
@@ -929,11 +950,13 @@ config_setting(
 
 config_setting(
     name = "dmlab_graphics_osmesa_or_glx",
+    constraint_values = ["@platforms//os:linux"],
     define_values = {"graphics": "osmesa_or_glx"},
 )
 
 config_setting(
     name = "dmlab_graphics_osmesa_or_egl",
+    constraint_values = ["@platforms//os:linux"],
     define_values = {"graphics": "osmesa_or_egl"},
 )
 
@@ -947,6 +970,7 @@ cc_binary(
     linkstatic = 1,
     visibility = ["//testing:__subpackages__"],
     deps = [":dmlab.lds"] + select({
+        "is_macos": [":game_lib_headless_macos"],
         "dmlab_graphics_osmesa_or_egl": [":game_lib_headless_egl"],
         "dmlab_graphics_osmesa_or_glx": [":game_lib_headless_glx"],
         "//conditions:default": [":game_lib_headless_egl"],
diff --git a/engine/code/deepmind/headless_macos_glimp.c b/engine/code/deepmind/headless_macos_glimp.c
new file mode 100644
index 000000000..659b704eb
--- /dev/null
+++ b/engine/code/deepmind/headless_macos_glimp.c
@@ -0,0 +1,58 @@
+#include <dlfcn.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <OpenGL/OpenGL.h>
+#include <OpenGL/gl3.h>
+
+#include "glimp_common.h"
+
+static CGLContextObj context;
+
+void GLimp_MakeCurrent(void) {
+}
+
+void GLimp_Init(void) {
+  CGLPixelFormatObj pix;
+  GLint npix;
+  int attribs[] = {
+    kCGLPFAAccelerated,     // no software rendering
+    kCGLPFAOpenGLProfile,
+    kCGLOGLPVersion_Legacy,
+    0
+  };
+
+  GLimp_CommonPreInit();
+
+  // NOTE: in headless mode there is no GUI, hence output to console instead of message boxes
+
+  if (CGLChoosePixelFormat((CGLPixelFormatAttribute*)attribs, &pix, &npix) != kCGLNoError) {
+    // Sys_Error("GLimp_Init - choose pixel format error!\n");
+    printf("GLimp_Init - choose pixel format error!\n");
+    exit(1);
+  }
+  if (CGLCreateContext(pix, NULL, &context) != kCGLNoError) {
+    // Sys_Error("GLimp_Init - create context error!\n");
+    printf("GLimp_Init - create context error!\n");
+    exit(1);
+  }
+  if (CGLSetCurrentContext(context) != kCGLNoError) {
+    // Sys_Error("GLimp_Init - set current context error!");
+    printf("GLimp_Init - set current context error!\n");
+    exit(1);
+  }
+  CGLDestroyPixelFormat(pix);
+
+  printf("Renderer: %s\nVersion: %s\n", glGetString(GL_RENDERER), glGetString(GL_VERSION));
+
+  GLimp_CommonPostInit();
+}
+
+void* GLimp_GetProcAddress(const char* func) {
+  return dlsym(RTLD_SELF, func);
+}
+
+void GLimp_Shutdown(void) {
+  CGLSetCurrentContext(NULL);
+  CGLDestroyContext(context);
+}