diff --git a/src/utils/compose.js b/src/utils/compose.js
index 23ce83a..6c006a7 100644
--- a/src/utils/compose.js
+++ b/src/utils/compose.js
@@ -7,7 +7,7 @@ const { ignoreGlobs } = require('./globs');
  */
 function compose(module, options) {
   const config = module(options);
-  config.ignores = [config.ignores, ...options.ignores, ...ignoreGlobs];
+  config.ignores = [...(config.ignores ?? []), ...(options.ignores ?? []), ...(ignoreGlobs ?? [])];
   return config;
 }