diff --git a/build_runner/CHANGELOG.md b/build_runner/CHANGELOG.md
index 388701ca8..732ce6d31 100644
--- a/build_runner/CHANGELOG.md
+++ b/build_runner/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 2.3.1
+
+- Upgrade to `frontend_service_client` version 3.
+
 ## 2.3.0
 
 - Add `-d` as a shorthand for `--delete-conflicting-outputs`.
diff --git a/build_runner/lib/src/build_script_generate/bootstrap.dart b/build_runner/lib/src/build_script_generate/bootstrap.dart
index 97bb290d8..8fc9bdaba 100644
--- a/build_runner/lib/src/build_script_generate/bootstrap.dart
+++ b/build_runner/lib/src/build_script_generate/bootstrap.dart
@@ -165,14 +165,12 @@ Future<int> _createKernelIfNeeded(Logger logger) async {
     await logTimedAsync(logger, 'Precompiling build script...', () async {
       try {
         final result = await client.compile();
-        hadErrors = result == null ||
-            result.errorCount > 0 ||
-            !(await kernelCacheFile.exists());
+        hadErrors = result.errorCount > 0 || !(await kernelCacheFile.exists());
 
         // Note: We're logging all output with a single log call to keep
         // annotated source spans intact.
-        final logOutput = result?.compilerOutputLines.join('\n');
-        if (logOutput != null && logOutput.isNotEmpty) {
+        final logOutput = result.compilerOutputLines.join('\n');
+        if (logOutput.isNotEmpty) {
           hadOutput = true;
           if (hadErrors) {
             // Always show compiler output if there were errors
diff --git a/build_runner/pubspec.yaml b/build_runner/pubspec.yaml
index 696e4e1d1..f3e014fa2 100644
--- a/build_runner/pubspec.yaml
+++ b/build_runner/pubspec.yaml
@@ -1,5 +1,5 @@
 name: build_runner
-version: 2.3.0
+version: 2.3.1
 description: A build system for Dart code generation and modular compilation.
 repository: https://github.com/dart-lang/build/tree/master/build_runner
 
@@ -19,7 +19,7 @@ dependencies:
   collection: ^1.15.0
   crypto: ^3.0.0
   dart_style: ^2.0.0
-  frontend_server_client: ^2.1.0
+  frontend_server_client: ^3.0.0
   glob: ^2.0.0
   graphs: ^2.0.0
   http_multi_server: ^3.0.0