diff --git a/BUILD.gn b/BUILD.gn
index 77e7db190..ce91fb10c 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -120,6 +120,7 @@ if (is_mac) {
   import("//build/config/mac/rules.gni")
   import("//build_overrides/v8.gni")
   import("//build/mac/tweak_info_plist.gni")
+  import("//build/util/version.gni")
   import("//media/cdm/ppapi/cdm_paths.gni")
 }
 if (is_win) {
@@ -164,8 +165,45 @@ if (is_mac) {
 #
 
 if (is_mac) {
-  # TODO(cef): Generate this value using version.py.
-  cef_version = "99.77.34.5"
+  cef_commit_number = exec_script(
+    "//cef/tools/commit_number.py",
+    [ rebase_path("//cef", root_build_dir) ],
+    "trim string", [])
+
+  cef_version_file = "//cef/VERSION"
+
+  # The tweak_info_plist.py script requires a version number with 4 parts. CEF
+  # uses a version number with 3 parts so just set the last part to 0.
+  cef_plist_version = exec_script(
+    "//build/util/version.py",
+    [
+      "-f",
+      rebase_path(cef_version_file, root_build_dir),
+      "-f",
+      rebase_path(chrome_version_file, root_build_dir),
+      "-t",
+      "@CEF_MAJOR@.@BUILD@.${cef_commit_number}.0",
+    ],
+    "trim string",
+    [ cef_version_file, chrome_version_file ])
+
+  # Need to be creative to match dylib version formatting requirements.
+  cef_dylib_version = exec_script(
+    "//build/util/version.py",
+    [
+      "-f",
+      rebase_path(cef_version_file, root_build_dir),
+      "-f",
+      rebase_path(chrome_version_file, root_build_dir),
+      "-t",
+      "@CEF_MAJOR@${cef_commit_number}.@BUILD_HI@.@BUILD_LO@",
+      "-e",
+      "BUILD_HI=int(BUILD)/256",
+      "-e",
+      "BUILD_LO=int(BUILD)%256",
+    ],
+    "trim string",
+    [ cef_version_file, chrome_version_file ])
 }
 
 # Read file lists from gypi files. The gypi_to_gn.py script does not support
@@ -1178,7 +1216,7 @@ if (is_mac) {
       "--keystone=0",
       "--scm=1",
       "--version",
-      cef_version,
+      cef_plist_version,
       "--branding",
       cef_framework_name,
     ]
@@ -1265,7 +1303,13 @@ if (is_mac) {
     # on one of the executables. However install_name_tool only operates
     # in-place, which is problematic to express in GN. Instead, use rpath-based
     # loading.
-    ldflags = [ "-Wl,-install_name,@rpath/Frameworks/$output_name.framework/$output_name" ]
+    ldflags = [
+      "-Wl,-install_name,@rpath/Frameworks/$output_name.framework/$output_name",
+      "-compatibility_version",
+      cef_dylib_version,
+      "-current_version",
+      cef_dylib_version,
+    ]
 
     if (is_component_build) {
       # Set up the rpath for the framework so that it can find dylibs in the
@@ -1345,7 +1389,7 @@ if (is_mac) {
         "--keystone=0",
         "--scm=0",
         "--version",
-        cef_version,
+        cef_plist_version,
       ]
     }
 
@@ -1396,7 +1440,7 @@ if (is_mac) {
       args = [
         "--scm=1",
         "--version",
-        cef_version,
+        cef_plist_version,
       ]
     }
 
diff --git a/tools/commit_number.py b/tools/commit_number.py
index 9865df899..bc03b1a51 100644
--- a/tools/commit_number.py
+++ b/tools/commit_number.py
@@ -11,7 +11,11 @@ if __name__ != "__main__":
     sys.stderr.write('This file cannot be loaded as a module!')
     sys.exit()
 
-if git.is_checkout('.'):
-  sys.stdout.write(git.get_commit_number())
+if len(sys.argv) < 2:
+  raise Exception('Path expected on command-line')
+
+path = sys.argv[1]
+if git.is_checkout(path):
+  sys.stdout.write(git.get_commit_number(path))
 else:
-  raise Exception('Not a valid checkout')
+  raise Exception('Not a valid checkout: ' + path)