diff --git a/packages/cli/src/lib/bundler/server.ts b/packages/cli/src/lib/bundler/server.ts
index 2e362cd050..a05baf5355 100644
--- a/packages/cli/src/lib/bundler/server.ts
+++ b/packages/cli/src/lib/bundler/server.ts
@@ -67,7 +67,7 @@ export async function serveBundle(options: ServeOptions) {
               cert: options.frontendConfig.getOptionalString(
                 'app.https.certificate.cert',
               ),
-              key: options.frontendConfig.getOptionalString(
+              key: options.backendConfig.getOptionalString(
                 'app.https.certificate.key',
               ),
             }
diff --git a/packages/cli/src/lib/bundler/types.ts b/packages/cli/src/lib/bundler/types.ts
index 4d6d2e5c9e..0d9d0f7af4 100644
--- a/packages/cli/src/lib/bundler/types.ts
+++ b/packages/cli/src/lib/bundler/types.ts
@@ -31,6 +31,8 @@ export type ServeOptions = BundlingPathsOptions & {
   checksEnabled: boolean;
   frontendConfig: Config;
   frontendAppConfigs: AppConfig[];
+  backendConfig: Config;
+  backendAppConfigs: AppConfig[];
 };
 
 export type BuildOptions = BundlingPathsOptions & {
diff --git a/packages/cli/src/lib/config.ts b/packages/cli/src/lib/config.ts
index e7ceeadf08..691c0ff83c 100644
--- a/packages/cli/src/lib/config.ts
+++ b/packages/cli/src/lib/config.ts
@@ -96,11 +96,20 @@ export async function loadCliConfig(options: Options) {
     });
     const frontendConfig = ConfigReader.fromConfigs(frontendAppConfigs);
 
+    const backendAppConfigs = schema.process(appConfigs, {
+      visibility: ['frontend', 'backend', 'secret'],
+      withFilteredKeys: options.withFilteredKeys,
+      withDeprecatedKeys: options.withDeprecatedKeys,
+    });
+    const backendConfig = ConfigReader.fromConfigs(backendAppConfigs);
+
     return {
       schema,
       appConfigs,
       frontendConfig,
       frontendAppConfigs,
+      backendAppConfigs,
+      backendConfig,
     };
   } catch (error) {
     const maybeSchemaError = error as Error & { messages?: string[] };
diff --git a/packages/core-app-api/config.d.ts b/packages/core-app-api/config.d.ts
index 42b1fd9245..6b707987e5 100644
--- a/packages/core-app-api/config.d.ts
+++ b/packages/core-app-api/config.d.ts
@@ -75,7 +75,7 @@ export interface Config {
       certificate?: {
         /**
          * Https Certificate private key. Use $file to load in a file
-         * @visibility frontend
+         * @visibility secret
          */
         key?: string;
         /**