diff --git a/BUILD.gn b/BUILD.gn
index 5fd2b638359..1aff52e981f 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -86,6 +86,12 @@ group("create_sdk") {
   ]
 }
 
+group("create_sdk_nnbd") {
+  public_deps = [
+    "sdk_nnbd:create_sdk_nnbd",
+  ]
+}
+
 if (defined(dart_host_sdk_toolchain) &&
     dart_host_sdk_toolchain != host_toolchain) {
   group("create_host_sdk") {
diff --git a/sdk_nnbd/BUILD.gn b/sdk_nnbd/BUILD.gn
index 9a4a1c59387..6d960001cd8 100644
--- a/sdk_nnbd/BUILD.gn
+++ b/sdk_nnbd/BUILD.gn
@@ -9,8 +9,8 @@
 #
 # Warning:
 # If you need to copy something into dart-sdk/lib/foo in addition to the stuff
-# copied there by :copy_libraries, then you must depend on ":copy_libraries",
-# or ":copy_libraries" may delete/overwrite your addition, and the build will
+# copied there by :copy_libraries_nnbd, then you must depend on ":copy_libraries_nnbd",
+# or ":copy_libraries_nnbd" may delete/overwrite your addition, and the build will
 # fail.
 
 import("../build/dart/copy_tree.gni")
@@ -18,12 +18,15 @@ import("../runtime/runtime_args.gni")
 
 declare_args() {
   # Build a SDK with less stuff. It excludes dart2js, ddc, and web libraries.
-  dart_platform_sdk = true
+  dart_platform_sdk_nnbd = true
 
   # Path to stripped dart binaries relative to build output directory.
-  dart_stripped_binary = "dart"
-  dartaotruntime_stripped_binary = "dartaotruntime"
-  gen_snapshot_stripped_binary = "gen_snapshot"
+  # TODO(rnystrom): These should use different filenames once the runtime's
+  # BUILD.gn file has additional rules to generate the NNBD versions of these
+  # executables.
+  dart_stripped_binary_nnbd = "dart"
+  dartaotruntime_stripped_binary_nnbd = "dartaotruntime"
+  gen_snapshot_stripped_binary_nnbd = "gen_snapshot"
 }
 
 # The directory layout of the SDK is as follows:
@@ -252,10 +255,10 @@ copy_tree_specs = []
 # bin/resources/dartdoc/templates
 copy_tree_specs += [
   {
-    target = "copy_dartdoc_templates"
-    visibility = [ ":copy_dartdoc_files" ]
+    target = "copy_dartdoc_templates_nnbd"
+    visibility = [ ":copy_dartdoc_files_nnbd" ]
     source = "../third_party/pkg/dartdoc/lib/templates"
-    dest = "$root_out_dir/dart-sdk/bin/resources/dartdoc/templates"
+    dest = "$root_out_dir/dart-sdk-nnbd/bin/resources/dartdoc/templates"
     ignore_patterns = "{}"
   },
 ]
@@ -264,10 +267,10 @@ copy_tree_specs += [
 # bin/resources/dartdoc/resources
 copy_tree_specs += [
   {
-    target = "copy_dartdoc_resources"
-    visibility = [ ":copy_dartdoc_files" ]
+    target = "copy_dartdoc_resources_nnbd"
+    visibility = [ ":copy_dartdoc_files_nnbd" ]
     source = "../third_party/pkg/dartdoc/lib/resources"
-    dest = "$root_out_dir/dart-sdk/bin/resources/dartdoc/resources"
+    dest = "$root_out_dir/dart-sdk-nnbd/bin/resources/dartdoc/resources"
     ignore_patterns = "{}"
   },
 ]
@@ -276,13 +279,13 @@ copy_tree_specs += [
 foreach(library, _full_sdk_libraries) {
   copy_tree_specs += [
     {
-      target = "copy_${library}_library"
+      target = "copy_${library}_library_nnbd"
       visibility = [
-        ":copy_platform_sdk_libraries",
-        ":copy_full_sdk_libraries",
+        ":copy_platform_sdk_libraries_nnbd",
+        ":copy_full_sdk_libraries_nnbd",
       ]
       source = "lib/$library"
-      dest = "$root_out_dir/dart-sdk/lib/$library"
+      dest = "$root_out_dir/dart-sdk-nnbd/lib/$library"
       ignore_patterns = "*.svn,doc,*.py,*.gypi,*.sh,.gitignore"
     },
   ]
@@ -291,13 +294,13 @@ foreach(library, _full_sdk_libraries) {
 if (is_win) {
   copy_tree_specs += [
     {
-      target = "copy_7zip"
-      visibility = [ ":create_common_sdk" ]
+      target = "copy_7zip_nnbd"
+      visibility = [ ":create_common_sdk_nnbd" ]
       deps = [
-        ":copy_libraries",
+        ":copy_libraries_nnbd",
       ]
       source = "../third_party/7zip"
-      dest = "$root_out_dir/dart-sdk/lib/_internal/pub/asset/7zip"
+      dest = "$root_out_dir/dart-sdk-nnbd/lib/_internal/pub/asset/7zip"
       ignore_patterns = ".svn"
     },
   ]
@@ -306,23 +309,23 @@ if (is_win) {
 if (target_cpu == "x64") {
   copy_tree_specs += [
     {
-      target = "copy_language_model"
-      visibility = [ ":create_common_sdk" ]
+      target = "copy_language_model_nnbd"
+      visibility = [ ":create_common_sdk_nnbd" ]
       deps = [
-        ":copy_libraries",
+        ":copy_libraries_nnbd",
       ]
       source = "../pkg/analysis_server/language_model"
-      dest = "$root_out_dir/dart-sdk/model"
+      dest = "$root_out_dir/dart-sdk-nnbd/model"
       ignore_patterns = "{}"
     },
     {
-      target = "copy_libtensorflowlite_c"
-      visibility = [ ":create_common_sdk" ]
+      target = "copy_libtensorflowlite_c_nnbd"
+      visibility = [ ":create_common_sdk_nnbd" ]
       deps = [
-        ":copy_libraries",
+        ":copy_libraries_nnbd",
       ]
       source = "../third_party/pkg/tflite_native/lib/src/blobs"
-      dest = "$root_out_dir/dart-sdk/bin/snapshots"
+      dest = "$root_out_dir/dart-sdk-nnbd/bin/snapshots"
       ignore_patterns = "{}"
     },
   ]
@@ -330,7 +333,7 @@ if (target_cpu == "x64") {
 
 # This generates targets for everything in copy_tree_specs. The targets have the
 # same name as the "target" fields in the scopes of copy_tree_specs.
-copy_trees("copy_trees") {
+copy_trees("copy_trees_nnbd") {
   sources = copy_tree_specs
 }
 
@@ -348,18 +351,19 @@ if (target_os != current_os && target_os == "fuchsia") {
   # make a link to the symlink rather than the symlink's target, and the
   # relative symlink interpreted from a different containing directory
   # will not find the actual binary.
-  action("copy_dart") {
-    visibility = [ ":create_common_sdk" ]
+  action("copy_dart_nnbd") {
+    visibility = [ ":create_common_sdk_nnbd" ]
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     dart_label = "../runtime/bin:dart"
     deps = [
       dart_label,
     ]
     dart_out = get_label_info(dart_label, "root_out_dir")
     sources = [
-      "$dart_out/$dart_stripped_binary",
+      "$dart_out/$dart_stripped_binary_nnbd",
     ]
     outputs = [
-      "$root_out_dir/dart-sdk/bin/$dart_stripped_binary",
+      "$root_out_dir/dart-sdk-nnbd/bin/$dart_stripped_binary_nnbd",
     ]
     script = "/bin/ln"
     args = [
@@ -369,31 +373,33 @@ if (target_os != current_os && target_os == "fuchsia") {
     ]
   }
 } else {
-  copy("copy_dart") {
-    visibility = [ ":create_common_sdk" ]
+  copy("copy_dart_nnbd") {
+    visibility = [ ":create_common_sdk_nnbd" ]
     deps = [
+      # TODO(rnystrom): This probably needs to be forked for NNBD.
       "../runtime/bin:dart",
     ]
     dart_out = get_label_info("../runtime/bin:dart", "root_out_dir")
     if (is_win) {
       sources = [
+        # TODO(rnystrom): This probably needs to be forked for NNBD.
         "$dart_out/dart.exe",
       ]
     } else {
       sources = [
-        "$dart_out/$dart_stripped_binary",
+        "$dart_out/$dart_stripped_binary_nnbd",
       ]
     }
     if (is_win) {
       sources += [ "$dart_out/dart.lib" ]
     }
     outputs = [
-      "$root_out_dir/dart-sdk/bin/{{source_file_part}}",
+      "$root_out_dir/dart-sdk-nnbd/bin/{{source_file_part}}",
     ]
   }
 }
 
-copy("copy_dartaotruntime") {
+copy("copy_dartaotruntime_nnbd") {
   deps = [
     "../runtime/bin:dartaotruntime",
   ]
@@ -405,38 +411,40 @@ copy("copy_dartaotruntime") {
     ]
   } else {
     sources = [
-      "$dartaotruntime_out/$dartaotruntime_stripped_binary",
+      "$dartaotruntime_out/$dartaotruntime_stripped_binary_nnbd",
     ]
   }
   if (is_win) {
     sources += [ "$dartaotruntime_out/dartaotruntime.lib" ]
   }
   outputs = [
-    "$root_out_dir/dart-sdk/bin/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/bin/{{source_file_part}}",
   ]
 }
 
-copy("copy_gen_snapshot") {
+copy("copy_gen_snapshot_nnbd") {
   deps = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "../runtime/bin:gen_snapshot",
   ]
   gen_snapshot_out =
       get_label_info("../runtime/bin:gen_snapshot", "root_out_dir")
   if (is_win) {
     sources = [
+      # TODO(rnystrom): This probably needs to be forked for NNBD.
       "$gen_snapshot_out/gen_snapshot.exe",
     ]
   } else {
     sources = [
-      "$gen_snapshot_out/$gen_snapshot_stripped_binary",
+      "$gen_snapshot_out/$gen_snapshot_stripped_binary_nnbd",
     ]
   }
   outputs = [
-    "$root_out_dir/dart-sdk/bin/utils/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/bin/utils/{{source_file_part}}",
   ]
 }
 
-copy("copy_dart2aot") {
+copy("copy_dart2aot_nnbd") {
   ext = ""
   if (is_win) {
     ext = ".bat"
@@ -445,14 +453,14 @@ copy("copy_dart2aot") {
     "bin/dart2aot$ext",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/bin/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/bin/{{source_file_part}}",
   ]
 }
 
-copy("copy_dart2native") {
+copy("copy_dart2native_nnbd") {
   deps = [
-    ":copy_gen_kernel_snapshot",
-    ":copy_gen_snapshot",
+    ":copy_gen_kernel_snapshot_nnbd",
+    ":copy_gen_snapshot_nnbd",
   ]
   ext = ""
   if (is_win) {
@@ -462,26 +470,27 @@ copy("copy_dart2native") {
     "bin/dart2native$ext",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/bin/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/bin/{{source_file_part}}",
   ]
 }
 
-copy("copy_gen_kernel_snapshot") {
+copy("copy_gen_kernel_snapshot_nnbd") {
   deps = [
     "../utils/gen_kernel",
   ]
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$root_gen_dir/gen_kernel.dart.snapshot",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/bin/snapshots/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/bin/snapshots/{{source_file_part}}",
   ]
 }
 
 # A template for copying the things in _platform_sdk_scripts and
 # _full_sdk_scripts into bin/
-template("copy_sdk_script") {
-  assert(defined(invoker.name), "copy_sdk_script must define 'name'")
+template("copy_sdk_script_nnbd") {
+  assert(defined(invoker.name), "copy_sdk_script_nnbd must define 'name'")
   name = invoker.name
   ext = ""
   if (is_win) {
@@ -489,29 +498,29 @@ template("copy_sdk_script") {
   }
   copy(target_name) {
     visibility = [
-      ":copy_platform_sdk_scripts",
-      ":copy_full_sdk_scripts",
+      ":copy_platform_sdk_scripts_nnbd",
+      ":copy_full_sdk_scripts_nnbd",
     ]
     sources = [
       "bin/${name}_sdk$ext",
     ]
     outputs = [
-      "$root_out_dir/dart-sdk/bin/$name$ext",
+      "$root_out_dir/dart-sdk-nnbd/bin/$name$ext",
     ]
   }
 }
 
 foreach(sdk_script, _full_sdk_scripts) {
-  copy_sdk_script("copy_${sdk_script}_script") {
+  copy_sdk_script_nnbd("copy_${sdk_script}_script_nnbd") {
     name = sdk_script
   }
 }
 
 foreach(script, _scripts) {
-  copy("copy_${script}_script") {
+  copy("copy_${script}_script_nnbd") {
     visibility = [
-      ":copy_platform_sdk_scripts",
-      ":copy_full_sdk_scripts",
+      ":copy_platform_sdk_scripts_nnbd",
+      ":copy_full_sdk_scripts_nnbd",
     ]
     ext = ""
     if (is_win) {
@@ -521,159 +530,164 @@ foreach(script, _scripts) {
       "bin/$script$ext",
     ]
     outputs = [
-      "$root_out_dir/dart-sdk/bin/{{source_file_part}}",
+      "$root_out_dir/dart-sdk-nnbd/bin/{{source_file_part}}",
     ]
   }
 }
 
 # This is the main target for copying scripts in _platform_sdk_scripts to bin/
-group("copy_platform_sdk_scripts") {
-  visibility = [ ":create_platform_sdk" ]
+group("copy_platform_sdk_scripts_nnbd") {
+  visibility = [ ":create_platform_sdk_nnbd" ]
   public_deps = []
   foreach(sdk_script, _platform_sdk_scripts) {
-    public_deps += [ ":copy_${sdk_script}_script" ]
+    public_deps += [ ":copy_${sdk_script}_script_nnbd" ]
   }
   foreach(script, _scripts) {
-    public_deps += [ ":copy_${script}_script" ]
+    public_deps += [ ":copy_${script}_script_nnbd" ]
   }
 }
 
 # This is the main target for copying scripts in _full_sdk_scripts to bin/
-group("copy_full_sdk_scripts") {
-  visibility = [ ":create_full_sdk" ]
+group("copy_full_sdk_scripts_nnbd") {
+  visibility = [ ":create_full_sdk_nnbd" ]
   public_deps = []
   foreach(sdk_script, _full_sdk_scripts) {
-    public_deps += [ ":copy_${sdk_script}_script" ]
+    public_deps += [ ":copy_${sdk_script}_script_nnbd" ]
   }
   foreach(script, _scripts) {
-    public_deps += [ ":copy_${script}_script" ]
+    public_deps += [ ":copy_${script}_script_nnbd" ]
   }
 }
 
 # This loop generates "copy" targets that put snapshots into bin/snapshots
 foreach(snapshot, _full_sdk_snapshots) {
-  copy("copy_${snapshot[0]}_snapshot") {
+  copy("copy_${snapshot[0]}_snapshot_nnbd") {
     visibility = [
-      ":copy_platform_sdk_snapshots",
-      ":copy_full_sdk_snapshots",
+      ":copy_platform_sdk_snapshots_nnbd",
+      ":copy_full_sdk_snapshots_nnbd",
     ]
     deps = [
       snapshot[1],
     ]
     sources = [
+      # TODO(rnystrom): This probably needs to be forked for NNBD.
       "$root_gen_dir/${snapshot[0]}.dart.snapshot",
     ]
     outputs = [
-      "$root_out_dir/dart-sdk/bin/snapshots/{{source_file_part}}",
+      "$root_out_dir/dart-sdk-nnbd/bin/snapshots/{{source_file_part}}",
     ]
   }
 }
 
 # This is the main rule for copying snapshots from _platform_sdk_snapshots to
 # bin/snapshots
-group("copy_platform_sdk_snapshots") {
-  visibility = [ ":create_platform_sdk" ]
+group("copy_platform_sdk_snapshots_nnbd") {
+  visibility = [ ":create_platform_sdk_nnbd" ]
   public_deps = []
   foreach(snapshot, _platform_sdk_snapshots) {
-    public_deps += [ ":copy_${snapshot[0]}_snapshot" ]
+    public_deps += [ ":copy_${snapshot[0]}_snapshot_nnbd" ]
   }
 }
 
 # This is the main rule for copying snapshots from _full_sdk_snapshots to
 # bin/snapshots
-group("copy_full_sdk_snapshots") {
-  visibility = [ ":create_full_sdk" ]
+group("copy_full_sdk_snapshots_nnbd") {
+  visibility = [ ":create_full_sdk_nnbd" ]
   public_deps = []
   foreach(snapshot, _full_sdk_snapshots) {
-    public_deps += [ ":copy_${snapshot[0]}_snapshot" ]
+    public_deps += [ ":copy_${snapshot[0]}_snapshot_nnbd" ]
   }
 }
 
 # This rule writes the .packages file for dartdoc resources.
-write_file("$root_out_dir/dart-sdk/bin/resources/dartdoc/.packages",
+write_file("$root_out_dir/dart-sdk-nnbd/bin/resources/dartdoc/.packages",
            "dartdoc:.")
 
 # This is the main rule for copying the files that dartdoc needs.
-group("copy_dartdoc_files") {
-  visibility = [ ":create_common_sdk" ]
+group("copy_dartdoc_files_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   public_deps = [
-    ":copy_dartdoc_resources",
-    ":copy_dartdoc_templates",
+    ":copy_dartdoc_resources_nnbd",
+    ":copy_dartdoc_templates_nnbd",
   ]
 }
 
 # This rule copies analyzer summaries to lib/_internal
-copy("copy_analysis_summaries") {
-  visibility = [ ":create_common_sdk" ]
+copy("copy_analysis_summaries_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   deps = [
-    ":copy_libraries",
+    ":copy_libraries_nnbd",
     "../utils/dartanalyzer:generate_summary_strong",
   ]
   sources = [
     "$root_gen_dir/strong.sum",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/_internal/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/_internal/{{source_file_part}}",
   ]
 }
 
 # This rule copies dill files to lib/_internal.
-copy("copy_vm_dill_files") {
-  visibility = [ ":create_common_sdk" ]
+copy("copy_vm_dill_files_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   deps = [
-    ":copy_libraries",
+    ":copy_libraries_nnbd",
     "../runtime/vm:kernel_platform_files",
   ]
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$root_out_dir/vm_platform_strong.dill",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/_internal/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/_internal/{{source_file_part}}",
   ]
 }
 
-copy("copy_abi_dill_files") {
-  visibility = [ ":create_sdk_with_abi_versions" ]
+copy("copy_abi_dill_files_nnbd") {
+  visibility = [ ":create_sdk_with_abi_versions_nnbd" ]
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "../tools/abiversions",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/_internal/abiversions",
+    "$root_out_dir/dart-sdk-nnbd/lib/_internal/abiversions",
   ]
 }
 
-copy("copy_dart2js_dill_files") {
-  visibility = [ ":create_full_sdk" ]
+copy("copy_dart2js_dill_files_nnbd") {
+  visibility = [ ":create_full_sdk_nnbd" ]
   deps = [
-    ":copy_libraries",
+    ":copy_libraries_nnbd",
     "../utils/compiler:compile_dart2js_platform",
     "../utils/compiler:compile_dart2js_server_platform",
   ]
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$root_out_dir/dart2js_platform.dill",
     "$root_out_dir/dart2js_server_platform.dill",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/_internal/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/_internal/{{source_file_part}}",
   ]
 }
 
 # This rule copies ddc summaries to lib/_internal
-copy("copy_dev_compiler_summary") {
-  visibility = [ ":copy_dev_compiler_sdk" ]
+copy("copy_dev_compiler_summary_nnbd") {
+  visibility = [ ":copy_dev_compiler_sdk_nnbd" ]
   deps = [
-    ":copy_libraries",
+    ":copy_libraries_nnbd",
     "../utils/dartdevc:dartdevc_kernel_sdk_outline",
     "../utils/dartdevc:dartdevc_sdk",
   ]
   gen_dir = get_label_info("../utils/dartdevc:dartdevc_sdk", "target_gen_dir")
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     # TODO(vsm): Remove post CFE.
     "$gen_dir/ddc_sdk.sum",
     "$gen_dir/kernel/ddc_sdk.dill",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/_internal/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/_internal/{{source_file_part}}",
   ]
 }
 
@@ -681,129 +695,135 @@ copy("copy_dev_compiler_summary") {
 # DDC to Kernel (DDK) migration.
 
 # This rule copies DDC's JS SDK and require.js to lib/dev_compiler/amd.
-copy("copy_dev_compiler_js_amd") {
-  visibility = [ ":copy_dev_compiler_js" ]
+copy("copy_dev_compiler_js_amd_nnbd") {
+  visibility = [ ":copy_dev_compiler_js_nnbd" ]
   deps = [
     "../utils/dartdevc:dartdevc_sdk",
   ]
   gen_dir = get_label_info("../utils/dartdevc:dartdevc_sdk", "target_gen_dir")
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$gen_dir/js/amd/dart_sdk.js",
     "$gen_dir/js/amd/dart_sdk.js.map",
     "../third_party/requirejs/require.js",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/dev_compiler/amd/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/dev_compiler/amd/{{source_file_part}}",
   ]
 }
 
 # This rule copies DDC's JS SDK and run.js to lib/dev_compiler/common.
-copy("copy_dev_compiler_js_common") {
-  visibility = [ ":copy_dev_compiler_js" ]
+copy("copy_dev_compiler_js_common_nnbd") {
+  visibility = [ ":copy_dev_compiler_js_nnbd" ]
   deps = [
     "../utils/dartdevc:dartdevc_sdk",
   ]
   gen_dir = get_label_info("../utils/dartdevc:dartdevc_sdk", "target_gen_dir")
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$gen_dir/js/common/dart_sdk.js",
     "$gen_dir/js/common/dart_sdk.js.map",
     "../pkg/dev_compiler/lib/js/common/run.js",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/dev_compiler/common/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/dev_compiler/common/{{source_file_part}}",
   ]
 }
 
 # This rule copies DDC's JS SDK to lib/dev_compiler/es6.
-copy("copy_dev_compiler_js_es6") {
-  visibility = [ ":copy_dev_compiler_js" ]
+copy("copy_dev_compiler_js_es6_nnbd") {
+  visibility = [ ":copy_dev_compiler_js_nnbd" ]
   deps = [
     "../utils/dartdevc:dartdevc_sdk",
   ]
   gen_dir = get_label_info("../utils/dartdevc:dartdevc_sdk", "target_gen_dir")
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$gen_dir/js/es6/dart_sdk.js",
     "$gen_dir/js/es6/dart_sdk.js.map",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/dev_compiler/es6/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/dev_compiler/es6/{{source_file_part}}",
   ]
 }
 
 # This rule copies DDK's JS SDK and require.js to lib/dev_compiler/kernel/amd.
-copy("copy_dev_compiler_js_amd_kernel") {
-  visibility = [ ":copy_dev_compiler_js" ]
+copy("copy_dev_compiler_js_amd_kernel_nnbd") {
+  visibility = [ ":copy_dev_compiler_js_nnbd" ]
   deps = [
     "../utils/dartdevc:dartdevc_kernel_sdk",
   ]
   gen_dir =
       get_label_info("../utils/dartdevc:dartdevc_kernel_sdk", "target_gen_dir")
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$gen_dir/kernel/amd/dart_sdk.js",
     "$gen_dir/kernel/amd/dart_sdk.js.map",
     "../third_party/requirejs/require.js",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/dev_compiler/kernel/amd/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/dev_compiler/kernel/amd/{{source_file_part}}",
   ]
 }
 
 # This rule copies DDK's JS SDK to lib/dev_compiler/kernel/common.
-copy("copy_dev_compiler_js_common_kernel") {
-  visibility = [ ":copy_dev_compiler_js" ]
+copy("copy_dev_compiler_js_common_kernel_nnbd") {
+  visibility = [ ":copy_dev_compiler_js_nnbd" ]
   deps = [
     "../utils/dartdevc:dartdevc_kernel_sdk",
   ]
   gen_dir =
       get_label_info("../utils/dartdevc:dartdevc_kernel_sdk", "target_gen_dir")
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$gen_dir/kernel/common/dart_sdk.js",
     "$gen_dir/kernel/common/dart_sdk.js.map",
     "../pkg/dev_compiler/lib/js/common/run.js",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/dev_compiler/kernel/common/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/dev_compiler/kernel/common/{{source_file_part}}",
   ]
 }
 
 # This rule copies DDK's JS SDK to lib/dev_compiler/kernel/es6.
-copy("copy_dev_compiler_js_es6_kernel") {
-  visibility = [ ":copy_dev_compiler_js" ]
+copy("copy_dev_compiler_js_es6_kernel_nnbd") {
+  visibility = [ ":copy_dev_compiler_js_nnbd" ]
   deps = [
     "../utils/dartdevc:dartdevc_kernel_sdk",
   ]
   gen_dir =
       get_label_info("../utils/dartdevc:dartdevc_kernel_sdk", "target_gen_dir")
   sources = [
+    # TODO(rnystrom): This probably needs to be forked for NNBD.
     "$gen_dir/kernel/es6/dart_sdk.js",
     "$gen_dir/kernel/es6/dart_sdk.js.map",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/dev_compiler/kernel/es6/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/dev_compiler/kernel/es6/{{source_file_part}}",
   ]
 }
 
 # Copies all of the JS artifacts needed by DDC.
-group("copy_dev_compiler_js") {
+group("copy_dev_compiler_js_nnbd") {
   visibility = [
-    ":copy_dev_compiler_sdk",
-    ":copy_dev_compiler_tools",
+    ":copy_dev_compiler_sdk_nnbd",
+    ":copy_dev_compiler_tools_nnbd",
   ]
   public_deps = [
-    ":copy_dev_compiler_js_amd",
-    ":copy_dev_compiler_js_amd_kernel",
-    ":copy_dev_compiler_js_common",
-    ":copy_dev_compiler_js_common_kernel",
-    ":copy_dev_compiler_js_es6",
-    ":copy_dev_compiler_js_es6_kernel",
+    ":copy_dev_compiler_js_amd_nnbd",
+    ":copy_dev_compiler_js_amd_kernel_nnbd",
+    ":copy_dev_compiler_js_common_nnbd",
+    ":copy_dev_compiler_js_common_kernel_nnbd",
+    ":copy_dev_compiler_js_es6_nnbd",
+    ":copy_dev_compiler_js_es6_kernel_nnbd",
   ]
 }
 
 # This rule copies tools to go along with ddc.
-copy("copy_dev_compiler_tools") {
-  visibility = [ ":copy_dev_compiler_sdk" ]
+copy("copy_dev_compiler_tools_nnbd") {
+  visibility = [ ":copy_dev_compiler_sdk_nnbd" ]
   deps = [
-    ":copy_dev_compiler_js",
+    ":copy_dev_compiler_js_nnbd",
     "../utils/dartdevc:dartdevc_web",
     "../utils/dartdevc:stack_trace_mapper",
   ]
@@ -813,91 +833,91 @@ copy("copy_dev_compiler_tools") {
     "$dart_out/dev_compiler/build/web/ddc_web_compiler.js",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/dev_compiler/web/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/dev_compiler/web/{{source_file_part}}",
   ]
 }
 
 # This is the main rule for copying ddc's dependencies to lib/
-group("copy_dev_compiler_sdk") {
-  visibility = [ ":create_full_sdk" ]
+group("copy_dev_compiler_sdk_nnbd") {
+  visibility = [ ":create_full_sdk_nnbd" ]
   public_deps = [
-    ":copy_dev_compiler_js",
-    ":copy_dev_compiler_summary",
-    ":copy_dev_compiler_tools",
+    ":copy_dev_compiler_js_nnbd",
+    ":copy_dev_compiler_summary_nnbd",
+    ":copy_dev_compiler_tools_nnbd",
   ]
 }
 
 # This rule copies header files to include/
-copy("copy_headers") {
-  visibility = [ ":create_common_sdk" ]
+copy("copy_headers_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   sources = [
     "../runtime/include/dart_api.h",
     "../runtime/include/dart_native_api.h",
     "../runtime/include/dart_tools_api.h",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/include/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/include/{{source_file_part}}",
   ]
 }
 
 # This rule copies libraries.json files to lib/
-copy("copy_libraries_specification") {
-  visibility = [ ":create_common_sdk" ]
+copy("copy_libraries_specification_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   sources = [
     "lib/libraries.json",
   ]
   deps = [
-    ":copy_libraries",
+    ":copy_libraries_nnbd",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/{{source_file_part}}",
   ]
 }
 
 # This is the main rule to copy libraries in _platform_sdk_libraries to lib/
-group("copy_platform_sdk_libraries") {
+group("copy_platform_sdk_libraries_nnbd") {
   visibility = [
-    ":create_platform_sdk",
-    ":copy_libraries",
+    ":create_platform_sdk_nnbd",
+    ":copy_libraries_nnbd",
   ]
   public_deps = []
   foreach(library, _platform_sdk_libraries) {
-    public_deps += [ ":copy_${library}_library" ]
+    public_deps += [ ":copy_${library}_library_nnbd" ]
   }
 }
 
 # This is the main rule to copy libraries in _full_sdk_libraries to lib/
-group("copy_full_sdk_libraries") {
+group("copy_full_sdk_libraries_nnbd") {
   visibility = [
-    ":create_full_sdk",
-    ":copy_libraries",
+    ":create_full_sdk_nnbd",
+    ":copy_libraries_nnbd",
   ]
   public_deps = []
   foreach(library, _full_sdk_libraries) {
-    public_deps += [ ":copy_${library}_library" ]
+    public_deps += [ ":copy_${library}_library_nnbd" ]
   }
 }
 
-group("copy_libraries") {
-  if (dart_platform_sdk) {
+group("copy_libraries_nnbd") {
+  if (dart_platform_sdk_nnbd) {
     public_deps = [
-      ":copy_platform_sdk_libraries",
+      ":copy_platform_sdk_libraries_nnbd",
     ]
   } else {
     public_deps = [
-      ":copy_full_sdk_libraries",
+      ":copy_full_sdk_libraries_nnbd",
     ]
   }
 }
 
 # This rule writes the version file.
-action("write_version_file") {
-  visibility = [ ":create_common_sdk" ]
+action("write_version_file_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   inputs = [
     "../tools/VERSION",
     "../.git/logs/HEAD",
   ]
-  output = "$root_out_dir/dart-sdk/version"
+  output = "$root_out_dir/dart-sdk-nnbd/version"
   outputs = [
     output,
   ]
@@ -909,12 +929,12 @@ action("write_version_file") {
 }
 
 # This rule writes the revision file.
-action("write_revision_file") {
-  visibility = [ ":create_common_sdk" ]
+action("write_revision_file_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   inputs = [
     "../.git/logs/HEAD",
   ]
-  output = "$root_out_dir/dart-sdk/revision"
+  output = "$root_out_dir/dart-sdk-nnbd/revision"
   outputs = [
     output,
   ]
@@ -932,48 +952,48 @@ action("write_revision_file") {
 # of the analyzer package do not support the new location of this file. We
 # should be able to remove the old file once we release a newer version of
 # analyzer and popular frameworks have migrated to use it.
-copy("copy_libraries_dart") {
-  visibility = [ ":create_common_sdk" ]
+copy("copy_libraries_dart_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   deps = [
-    ":copy_libraries",
+    ":copy_libraries_nnbd",
   ]
   sources = [
     "lib/_internal/sdk_library_metadata/lib/libraries.dart",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/_internal/{{source_file_part}}",
+    "$root_out_dir/dart-sdk-nnbd/lib/_internal/{{source_file_part}}",
   ]
 }
 
 # This rule copies the README file.
-copy("copy_readme") {
-  visibility = [ ":create_common_sdk" ]
+copy("copy_readme_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   sources = [
     "../README.dart-sdk",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/README",
+    "$root_out_dir/dart-sdk-nnbd/README",
   ]
 }
 
 # This rule copies the LICENSE file.
-copy("copy_license") {
-  visibility = [ ":create_common_sdk" ]
+copy("copy_license_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   sources = [
     "../LICENSE",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/LICENSE",
+    "$root_out_dir/dart-sdk-nnbd/LICENSE",
   ]
 }
 
 # This rule generates a custom dartdoc_options.yaml file.
-action("write_dartdoc_options") {
-  visibility = [ ":create_common_sdk" ]
+action("write_dartdoc_options_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   inputs = [
     "../.git/logs/HEAD",
   ]
-  output = "$root_out_dir/dart-sdk/dartdoc_options.yaml"
+  output = "$root_out_dir/dart-sdk-nnbd/dartdoc_options.yaml"
   outputs = [
     output,
   ]
@@ -985,85 +1005,85 @@ action("write_dartdoc_options") {
 }
 
 # This rule copies the API readme file to lib/
-copy("copy_api_readme") {
-  visibility = [ ":create_common_sdk" ]
+copy("copy_api_readme_nnbd") {
+  visibility = [ ":create_common_sdk_nnbd" ]
   sources = [
     "api_readme.md",
   ]
   outputs = [
-    "$root_out_dir/dart-sdk/lib/api_readme.md",
+    "$root_out_dir/dart-sdk-nnbd/lib/api_readme.md",
   ]
 }
 
 # Parts common to both platform and full SDKs.
-group("create_common_sdk") {
-  visibility = [ ":create_sdk" ]
+group("create_common_sdk_nnbd") {
+  visibility = [ ":create_sdk_nnbd" ]
   public_deps = [
-    ":copy_analysis_summaries",
-    ":copy_api_readme",
-    ":copy_dart",
-    ":copy_dart2native",
-    ":copy_dartdoc_files",
-    ":copy_headers",
-    ":copy_libraries_dart",
-    ":copy_libraries_specification",
-    ":copy_license",
-    ":copy_readme",
-    ":copy_vm_dill_files",
-    ":write_dartdoc_options",
-    ":write_revision_file",
-    ":write_version_file",
+    ":copy_analysis_summaries_nnbd",
+    ":copy_api_readme_nnbd",
+    ":copy_dart_nnbd",
+    ":copy_dart2native_nnbd",
+    ":copy_dartdoc_files_nnbd",
+    ":copy_headers_nnbd",
+    ":copy_libraries_dart_nnbd",
+    ":copy_libraries_specification_nnbd",
+    ":copy_license_nnbd",
+    ":copy_readme_nnbd",
+    ":copy_vm_dill_files_nnbd",
+    ":write_dartdoc_options_nnbd",
+    ":write_revision_file_nnbd",
+    ":write_version_file_nnbd",
   ]
   if (is_win) {
-    public_deps += [ ":copy_7zip" ]
+    public_deps += [ ":copy_7zip_nnbd" ]
   }
   if (target_cpu == "x64") {
     public_deps += [
-      ":copy_language_model",
-      ":copy_libtensorflowlite_c",
+      ":copy_language_model_nnbd",
+      ":copy_libtensorflowlite_c_nnbd",
     ]
   }
 }
 
 # Parts specific to the platform SDK.
-group("create_platform_sdk") {
-  visibility = [ ":create_sdk" ]
+group("create_platform_sdk_nnbd") {
+  visibility = [ ":create_sdk_nnbd" ]
   public_deps = [
-    ":copy_platform_sdk_libraries",
-    ":copy_platform_sdk_scripts",
-    ":copy_platform_sdk_snapshots",
+    ":copy_platform_sdk_libraries_nnbd",
+    ":copy_platform_sdk_scripts_nnbd",
+    ":copy_platform_sdk_snapshots_nnbd",
   ]
 }
 
 # Parts specific to the full SDK.
-group("create_full_sdk") {
-  visibility = [ ":create_sdk" ]
+group("create_full_sdk_nnbd") {
+  visibility = [ ":create_sdk_nnbd" ]
 
   public_deps = [
-    ":copy_dart2js_dill_files",
-    ":copy_dev_compiler_sdk",
-    ":copy_full_sdk_libraries",
-    ":copy_full_sdk_scripts",
-    ":copy_full_sdk_snapshots",
+    ":copy_dart2js_dill_files_nnbd",
+    ":copy_dev_compiler_sdk_nnbd",
+    ":copy_full_sdk_libraries_nnbd",
+    ":copy_full_sdk_scripts_nnbd",
+    ":copy_full_sdk_snapshots_nnbd",
   ]
 }
 
 # The main target to depend on from ../BUILD.gn
-group("create_sdk") {
+group("create_sdk_nnbd") {
   public_deps = [
-    ":create_common_sdk",
+    ":create_common_sdk_nnbd",
   ]
-  if (dart_platform_sdk) {
-    public_deps += [ ":create_platform_sdk" ]
+  if (dart_platform_sdk_nnbd) {
+    public_deps += [ ":create_platform_sdk_nnbd" ]
   } else {
-    public_deps += [ ":create_full_sdk" ]
+    public_deps += [ ":create_full_sdk_nnbd" ]
   }
 }
 
 # Same as create_sdk, but with abi version files.
-group("create_sdk_with_abi_versions") {
+group("create_sdk_with_abi_versions_nnbd") {
   public_deps = [
-    ":copy_abi_dill_files",
-    ":create_sdk",
+    ":copy_abi_dill_files_nnbd",
+    ":create_sdk_nnbd",
   ]
-}
+}
\ No newline at end of file