diff --git a/packages/angular/build/src/builders/karma/progress-reporter.ts b/packages/angular/build/src/builders/karma/progress-reporter.ts
index c4f573e9a2b2..908f1c856e6d 100644
--- a/packages/angular/build/src/builders/karma/progress-reporter.ts
+++ b/packages/angular/build/src/builders/karma/progress-reporter.ts
@@ -40,6 +40,8 @@ export function injectKarmaReporter(
 
   class ProgressNotifierReporter {
     static $inject = ['emitter', LATEST_BUILD_FILES_TOKEN];
+    // Needed for the karma reporter interface, see https://github.com/angular/angular-cli/issues/31629
+    adapters = [];
 
     constructor(
       private readonly emitter: KarmaEmitter,