diff --git a/web_sdk/BUILD.gn b/web_sdk/BUILD.gn
index bbebc9c0b3efb..788f8caa49bf0 100644
--- a/web_sdk/BUILD.gn
+++ b/web_sdk/BUILD.gn
@@ -153,35 +153,55 @@ copy("web_ui_library") {
 #
 #   args (required): The arguments to pass to dartdevc
 template("_dartdevc") {
-  assert(flutter_prebuilt_dart_sdk,
-         "Cannot build web sdk without prebuilt dart sdk")
-  action(target_name) {
-    not_needed(invoker, [ "packages" ])
-    deps = [
-      ":skwasm_impl_library",
-      ":skwasm_stub_library",
-      ":web_engine_library",
-      ":web_ui_library",
-      ":web_ui_library_sources",
-    ]
-    script = "//build/gn_run_binary.py"
+  if (flutter_prebuilt_dart_sdk) {
+    action(target_name) {
+      not_needed(invoker, [ "packages" ])
+      deps = [
+        ":skwasm_impl_library",
+        ":skwasm_stub_library",
+        ":web_engine_library",
+        ":web_ui_library",
+        ":web_ui_library_sources",
+      ]
+      script = "//build/gn_run_binary.py"
+
+      inputs = invoker.inputs
+      outputs = invoker.outputs
+
+      pool = "//flutter/build/dart:dart_pool"
+
+      ext = ""
+      if (is_win) {
+        ext = ".exe"
+      }
+      dart = rebase_path("$host_prebuilt_dart_sdk/bin/dart$ext", root_out_dir)
+      dartdevc = rebase_path(
+              "$host_prebuilt_dart_sdk/bin/snapshots/dartdevc.dart.snapshot")
+      args = [
+               dart,
+               dartdevc,
+             ] + invoker.args
+    }
+  } else {
+    prebuilt_dart_action(target_name) {
+      forward_variables_from(invoker, "*")
+
+      deps = [
+        ":skwasm_impl_library",
+        ":skwasm_stub_library",
+        ":web_engine_library",
+        ":web_ui_library",
+        ":web_ui_library_sources",
+        "//third_party/dart:create_sdk",
+        "//third_party/dart/pkg:pkg_files_stamp",
+        "//third_party/dart/utils/dartdevc:dartdevc_files_stamp",
+        "//third_party/dart/utils/dartdevc:dartdevc_sdk_patch_stamp",
+      ]
 
-    inputs = invoker.inputs
-    outputs = invoker.outputs
+      script = "//third_party/dart/pkg/dev_compiler/bin/dartdevc.dart"
 
-    pool = "//flutter/build/dart:dart_pool"
-
-    ext = ""
-    if (is_win) {
-      ext = ".exe"
+      pool = "//flutter/build/dart:dart_pool"
     }
-    dart = rebase_path("$host_prebuilt_dart_sdk/bin/dart$ext", root_out_dir)
-    dartdevc = rebase_path(
-            "$host_prebuilt_dart_sdk/bin/snapshots/dartdevc.dart.snapshot")
-    args = [
-             dart,
-             dartdevc,
-           ] + invoker.args
   }
 }
 
@@ -195,35 +215,55 @@ template("_dartdevc") {
 #
 #   args (required): The arguments to pass to the kernel_worker
 template("_kernel_worker") {
-  assert(flutter_prebuilt_dart_sdk,
-         "Cannot build web sdk without prebuilt dart sdk")
-  action(target_name) {
-    deps = [
-      ":skwasm_impl_library",
-      ":skwasm_stub_library",
-      ":web_engine_library",
-      ":web_ui_library",
-      ":web_ui_library_sources",
-    ]
-    script = "//build/gn_run_binary.py"
+  if (flutter_prebuilt_dart_sdk) {
+    action(target_name) {
+      deps = [
+        ":skwasm_impl_library",
+        ":skwasm_stub_library",
+        ":web_engine_library",
+        ":web_ui_library",
+        ":web_ui_library_sources",
+      ]
+      script = "//build/gn_run_binary.py"
 
-    inputs = invoker.inputs
-    outputs = invoker.outputs
+      inputs = invoker.inputs
+      outputs = invoker.outputs
 
-    pool = "//flutter/build/dart:dart_pool"
+      pool = "//flutter/build/dart:dart_pool"
+
+      ext = ""
+      if (is_win) {
+        ext = ".exe"
+      }
+      dart = rebase_path("$host_prebuilt_dart_sdk/bin/dart$ext", root_out_dir)
+      kernel_worker = rebase_path(
+              "$host_prebuilt_dart_sdk/bin/snapshots/kernel_worker.dart.snapshot")
 
-    ext = ""
-    if (is_win) {
-      ext = ".exe"
+      args = [
+               dart,
+               kernel_worker,
+             ] + invoker.args
     }
-    dart = rebase_path("$host_prebuilt_dart_sdk/bin/dart$ext", root_out_dir)
-    kernel_worker = rebase_path(
-            "$host_prebuilt_dart_sdk/bin/snapshots/kernel_worker.dart.snapshot")
+  } else {
+    prebuilt_dart_action(target_name) {
+      forward_variables_from(invoker, "*")
+
+      deps = [
+        ":skwasm_impl_library",
+        ":skwasm_stub_library",
+        ":web_engine_library",
+        ":web_ui_library",
+        ":web_ui_library_sources",
+        "//third_party/dart:create_sdk",
+        "//third_party/dart/pkg:pkg_files_stamp",
+        "//third_party/dart/utils/dartdevc:dartdevc_files_stamp",
+        "//third_party/dart/utils/dartdevc:dartdevc_sdk_patch_stamp",
+      ]
 
-    args = [
-             dart,
-             kernel_worker,
-           ] + invoker.args
+      script = "//third_party/dart/utils/bazel/kernel_worker.dart"
+
+      pool = "//flutter/build/dart:dart_pool"
+    }
   }
 }
 
@@ -253,8 +293,6 @@ template("_compile_outline") {
       "org-dartlang-sdk",
       "--multi-root",
       "file:///" + rebase_path("$root_out_dir/flutter_web_sdk"),
-      "--multi-root",
-      "file:///" + rebase_path("$host_prebuilt_dart_sdk/.."),
       "--libraries-file",
       "org-dartlang-sdk:///libraries.json",
       "--output",
@@ -270,6 +308,17 @@ template("_compile_outline") {
       "--source",
       "dart:_skwasm_stub",
     ]
+    if (flutter_prebuilt_dart_sdk) {
+      args += [
+        "--multi-root",
+        "file:///" + rebase_path("$host_prebuilt_dart_sdk/.."),
+      ]
+    } else {
+      args += [
+        "--multi-root",
+        "file:///" + rebase_path("$root_out_dir"),
+      ]
+    }
   }
 }
 
@@ -342,8 +391,6 @@ template("_compile_ddc_modules") {
       "org-dartlang-sdk",
       "--multi-root",
       "file:///" + rebase_path("$root_out_dir/flutter_web_sdk"),
-      "--multi-root",
-      "file:///" + rebase_path("$host_prebuilt_dart_sdk/.."),
       "--multi-root-output-path",
       rebase_path("$root_out_dir/"),
       "--libraries-file",
@@ -360,6 +407,17 @@ template("_compile_ddc_modules") {
       "-o",
       rebase_path(legacy_js_path),
     ]
+    if (flutter_prebuilt_dart_sdk) {
+      args += [
+        "--multi-root",
+        "file:///" + rebase_path("$host_prebuilt_dart_sdk/.."),
+      ]
+    } else {
+      args += [
+        "--multi-root",
+        "file:///" + rebase_path("$root_out_dir"),
+      ]
+    }
   }
 }