diff --git a/src/node/config.ts b/src/node/config.ts
index cfdcfe71..f5625643 100644
--- a/src/node/config.ts
+++ b/src/node/config.ts
@@ -20,7 +20,7 @@ export interface UserConfig<ThemeConfig = any> {
   locales?: Record<string, LocaleConfig>
   alias?: Record<string, string>
   markdown?: MarkdownOptions
-  // TODO locales support etc.
+  customData?: any
 }
 
 export interface SiteConfig<ThemeConfig = any> {
@@ -91,6 +91,7 @@ export async function resolveSiteData(root: string): Promise<SiteData> {
     base: userConfig.base ? userConfig.base.replace(/([^/])$/, '$1/') : '/',
     head: userConfig.head || [],
     themeConfig: userConfig.themeConfig || {},
-    locales: userConfig.locales || {}
+    locales: userConfig.locales || {},
+    customData: userConfig.customData || {}
   }
 }
diff --git a/types/shared.d.ts b/types/shared.d.ts
index cf2aa73a..1f14a6a5 100644
--- a/types/shared.d.ts
+++ b/types/shared.d.ts
@@ -17,6 +17,7 @@ export interface SiteData<ThemeConfig = any> {
   head: HeadConfig[]
   themeConfig: ThemeConfig
   locales: Record<string, LocaleConfig>
+  customData: any
 }
 
 export type HeadConfig =