diff --git a/packages/concatjs/internal/tsc_wrapped/tsconfig.ts b/packages/concatjs/internal/tsc_wrapped/tsconfig.ts
index 1117ea892d..ca21ce3ef5 100644
--- a/packages/concatjs/internal/tsc_wrapped/tsconfig.ts
+++ b/packages/concatjs/internal/tsc_wrapped/tsconfig.ts
@@ -38,11 +38,18 @@ export interface BazelOptions {
   googmodule: boolean;
 
   /**
+   * DEPRECATED. being replaced by devmode.
    * If true, emit devmode output into filename.js.
    * If false, emit prodmode output into filename.mjs.
    */
   es5Mode: boolean;
 
+  /**
+   * If true, emit devmode output into filename.js.
+   * If false, emit prodmode output into filename.mjs.
+   */
+  devmode: boolean;
+
   /** If true, convert TypeScript code into a Closure-compatible variant. */
   tsickle: boolean;