diff --git a/env.mjs b/env.mjs
index b3e960a..fe2dda5 100644
--- a/env.mjs
+++ b/env.mjs
@@ -24,18 +24,18 @@ export const env = createEnv({
   },
   runtimeEnv: {
     NEXTAUTH_URL: process.env.NEXTAUTH_URL,
-    NEXTAUTH_SECRET: process.env.NEXTAUTH_SECRET,
-    GITHUB_CLIENT_ID: process.env.GITHUB_CLIENT_ID,
-    GITHUB_CLIENT_SECRET: process.env.GITHUB_CLIENT_SECRET,
-    GITHUB_ACCESS_TOKEN: process.env.GITHUB_ACCESS_TOKEN,
-    DATABASE_URL: process.env.DATABASE_URL,
-    SMTP_FROM: process.env.SMTP_FROM,
-    POSTMARK_API_TOKEN: process.env.POSTMARK_API_TOKEN,
-    POSTMARK_SIGN_IN_TEMPLATE: process.env.POSTMARK_SIGN_IN_TEMPLATE,
-    POSTMARK_ACTIVATION_TEMPLATE: process.env.POSTMARK_ACTIVATION_TEMPLATE,
-    STRIPE_API_KEY: process.env.STRIPE_API_KEY,
-    STRIPE_WEBHOOK_SECRET: process.env.STRIPE_WEBHOOK_SECRET,
-    STRIPE_PRO_MONTHLY_PLAN_ID: process.env.STRIPE_PRO_MONTHLY_PLAN_ID,
-    NEXT_PUBLIC_APP_URL: process.env.NEXT_PUBLIC_APP_URL,
+    NEXTAUTH_SECRET: process.env.NEXTAUTH_SECRET || "nextauth_secret_placeholder",
+    GITHUB_CLIENT_ID: process.env.GITHUB_CLIENT_ID || "github_client_id_placeholder",
+    GITHUB_CLIENT_SECRET: process.env.GITHUB_CLIENT_SECRET || "github_client_secret_placeholder",
+    GITHUB_ACCESS_TOKEN: process.env.GITHUB_ACCESS_TOKEN || "github_access_token_placeholder",
+    DATABASE_URL: process.env.DATABASE_URL || "database_url_placeholder",
+    SMTP_FROM: process.env.SMTP_FROM || "smtp_from_placeholder",
+    POSTMARK_API_TOKEN: process.env.POSTMARK_API_TOKEN || "postmark_api_token_placeholder",
+    POSTMARK_SIGN_IN_TEMPLATE: process.env.POSTMARK_SIGN_IN_TEMPLATE || "postmark_sign_in_template_placeholder",
+    POSTMARK_ACTIVATION_TEMPLATE: process.env.POSTMARK_ACTIVATION_TEMPLATE || "postmark_activation_template_placeholder",
+    STRIPE_API_KEY: process.env.STRIPE_API_KEY || "stripe_api_key_placeholder",
+    STRIPE_WEBHOOK_SECRET: process.env.STRIPE_WEBHOOK_SECRET || "stripe_webhook_secret_placeholder",
+    STRIPE_PRO_MONTHLY_PLAN_ID: process.env.STRIPE_PRO_MONTHLY_PLAN_ID || "stripe_pro_monthly_plan_id_placeholder",
+    NEXT_PUBLIC_APP_URL: process.env.NEXT_PUBLIC_APP_URL || "next_public_app_url_placeholder",
   },
 })