diff --git a/shell/platform/fuchsia/dart_runner/BUILD.gn b/shell/platform/fuchsia/dart_runner/BUILD.gn
index c69df5c1222b650fca8cb6f98fd01c7bee7327b0..4e3f514608a3a6168bc6f05fea50c7098b5a7ee0 100644
--- a/shell/platform/fuchsia/dart_runner/BUILD.gn
+++ b/shell/platform/fuchsia/dart_runner/BUILD.gn
@@ -18,6 +18,9 @@ template("runner") {
   invoker_output_name = invoker.output_name
   extra_defines = invoker.extra_defines
   extra_deps = invoker.extra_deps
+  if (is_debug) {
+    extra_defines += [ "DEBUG" ]  # Needed due to direct dart dependencies.
+  }
 
   executable(target_name) {
     output_name = invoker_output_name
diff --git a/shell/platform/fuchsia/flutter/BUILD.gn b/shell/platform/fuchsia/flutter/BUILD.gn
index c8652cc9a05984dc115e7ffba48158ff45c4b950..5161fe869bd7811abc7e0f9cfd1b12ce117798f1 100644
--- a/shell/platform/fuchsia/flutter/BUILD.gn
+++ b/shell/platform/fuchsia/flutter/BUILD.gn
@@ -146,6 +146,9 @@ template("flutter_runner") {
   if (defined(invoker.extra_defines)) {
     extra_defines += invoker.extra_defines
   }
+  if (is_debug) {
+    extra_defines += [ "DEBUG" ]  # Needed due to direct dart dependencies.
+  }
 
   executable(target_name) {
     output_name = invoker_output_name
diff --git a/tools/fuchsia/build_fuchsia_artifacts.py b/tools/fuchsia/build_fuchsia_artifacts.py
index cfe4fe6f0ace1538bce53122190dd08429f9f32d..c9b657599e996260d1724526de7eeb44ae3d4de9 100755
--- a/tools/fuchsia/build_fuchsia_artifacts.py
+++ b/tools/fuchsia/build_fuchsia_artifacts.py
@@ -167,9 +167,10 @@ def CopyIcuDepsToBucket(src, dst):
   deps_bucket_path = os.path.join(_bucket_directory, dst)
   FindFileAndCopyTo('icudtl.dat', source_root, deps_bucket_path)
 
-def BuildBucket(runtime_mode, arch, product):
-  out_dir = 'fuchsia_%s_%s/' % (runtime_mode, arch)
-  bucket_dir = 'flutter/%s/%s/' % (arch, runtime_mode)
+def BuildBucket(runtime_mode, arch, optimized, product):
+  unopt = "_unopt" if not optimized else ""
+  out_dir = 'fuchsia_%s%s_%s/' % (runtime_mode, unopt, arch)
+  bucket_dir = 'flutter/%s/%s%s/' % (arch, runtime_mode, unopt)
   deps_dir = 'flutter/%s/deps/' % (arch)
   CopyToBucket(out_dir, bucket_dir, product)
   CopyVulkanDepsToBucket(out_dir, deps_dir, arch)
@@ -244,8 +245,9 @@ def GetRunnerTarget(runner_type, product, aot):
   target += 'runner'
   return base + target
 
-def BuildTarget(runtime_mode, arch, enable_lto, additional_targets=[]):
-  out_dir = 'fuchsia_%s_%s' % (runtime_mode, arch)
+def BuildTarget(runtime_mode, arch, optimized, enable_lto, asan, additional_targets=[]):
+  unopt = "_unopt" if not optimized else ""
+  out_dir = 'fuchsia_%s%s_%s' % (runtime_mode, unopt, arch)
   flags = [
       '--fuchsia',
       '--fuchsia-cpu',
@@ -254,8 +256,13 @@ def BuildTarget(runtime_mode, arch, enable_lto, additional_targets=[]):
       runtime_mode,
   ]
 
+  if not optimized:
+    flags.append('--unoptimized')
+
   if not enable_lto:
     flags.append('--no-lto')
+  if asan:
+    flags.append('--asan')
 
   RunGN(out_dir, flags)
   BuildNinjaTargets(out_dir, [ 'flutter' ] + additional_targets)
@@ -277,6 +284,12 @@ def main():
       required=False,
       help='Specifies the flutter engine SHA.')
 
+  parser.add_argument(
+      '--unoptimized',
+      action='store_true',
+      default=False,
+      help='If set, disables compiler optimization for the build.')
+
   parser.add_argument(
       '--runtime-mode',
       type=str,
@@ -286,6 +299,12 @@ def main():
   parser.add_argument(
       '--archs', type=str, choices=['x64', 'arm64', 'all'], default='all')
 
+  parser.add_argument(
+      '--asan',
+      action='store_true',
+      default=False,
+      help='If set, enables address sanitization (including leak sanitization) for the build.')
+
   parser.add_argument(
       '--no-lto',
       action='store_true',
@@ -312,6 +331,7 @@ def main():
   runtime_modes = ['debug', 'profile', 'release']
   product_modes = [False, False, True]
 
+  optimized = not args.unoptimized
   enable_lto = not args.no_lto
 
   for arch in archs:
@@ -320,8 +340,8 @@ def main():
       product = product_modes[i]
       if build_mode == 'all' or runtime_mode == build_mode:
         if not args.skip_build:
-          BuildTarget(runtime_mode, arch, enable_lto, args.targets.split(","))
-        BuildBucket(runtime_mode, arch, product)
+          BuildTarget(runtime_mode, arch, optimized, enable_lto, args.asan, args.targets.split(","))
+        BuildBucket(runtime_mode, arch, optimized, product)
 
   if args.upload:
     if args.engine_version is None: