diff --git a/plugins/techdocs-backend/config.d.ts b/plugins/techdocs-backend/config.d.ts
index 01da1e7926..9d1cd9e170 100644
--- a/plugins/techdocs-backend/config.d.ts
+++ b/plugins/techdocs-backend/config.d.ts
@@ -24,7 +24,7 @@ export interface Config {
      * Documentation building process depends on the builder attr
      * @visibility frontend
      */
-    builder: 'local' | 'external';
+    builder?: 'local' | 'external';
 
     /**
      * Techdocs generator information
diff --git a/plugins/techdocs-backend/src/service/DefaultDocsBuildStrategy.ts b/plugins/techdocs-backend/src/service/DefaultDocsBuildStrategy.ts
index bc2c586c82..a0bd623b64 100644
--- a/plugins/techdocs-backend/src/service/DefaultDocsBuildStrategy.ts
+++ b/plugins/techdocs-backend/src/service/DefaultDocsBuildStrategy.ts
@@ -29,6 +29,8 @@ export class DefaultDocsBuildStrategy implements DocsBuildStrategy {
   }
 
   async shouldBuild(_: { entity: Entity }): Promise<boolean> {
-    return this.config.getString('techdocs.builder') === 'local';
+    return [undefined, 'local'].includes(
+      this.config.getOptionalString('techdocs.builder'),
+    );
   }
 }
diff --git a/plugins/techdocs/config.d.ts b/plugins/techdocs/config.d.ts
index 82ae8dd87a..0df852e490 100644
--- a/plugins/techdocs/config.d.ts
+++ b/plugins/techdocs/config.d.ts
@@ -24,7 +24,7 @@ export interface Config {
      * Documentation building process depends on the builder attr
      * @visibility frontend
      */
-    builder: 'local' | 'external';
+    builder?: 'local' | 'external';
 
     /**
      * Allows fallback to case-sensitive triplets in case of migration issues.
diff --git a/plugins/techdocs/src/client.ts b/plugins/techdocs/src/client.ts
index ae81ecdaaa..0f11eb4068 100644
--- a/plugins/techdocs/src/client.ts
+++ b/plugins/techdocs/src/client.ts
@@ -151,7 +151,7 @@ export class TechDocsStorageClient implements TechDocsStorageApi {
   }
 
   async getBuilder(): Promise<string> {
-    return this.configApi.getString('techdocs.builder');
+    return this.configApi.getOptionalString('techdocs.builder') || 'local';
   }
 
   /**
diff --git a/plugins/techdocs/src/reader/components/TechDocsNotFound.tsx b/plugins/techdocs/src/reader/components/TechDocsNotFound.tsx
index bd2ef26b1e..858f9c5afc 100644
--- a/plugins/techdocs/src/reader/components/TechDocsNotFound.tsx
+++ b/plugins/techdocs/src/reader/components/TechDocsNotFound.tsx
@@ -39,7 +39,7 @@ export const TechDocsNotFound = ({ errorMessage }: Props) => {
   }, [analyticsApi, entityRef, location]);
 
   let additionalInfo = '';
-  if (techdocsBuilder !== 'local') {
+  if (![undefined, 'local'].includes(techdocsBuilder)) {
     additionalInfo =
       "Note that techdocs.builder is not set to 'local' in your config, which means this Backstage app will not " +
       "generate docs if they are not found. Make sure the project's docs are generated and published by some external " +