You are not sending the response object. You are just assigning a string to an undeclared variable Response.
The syntax is:
res.json({"someKey": "someValue"})
Then, in the /json GET route handler you created in the last challenge, transform the response object’s message to uppercase if process.env.MESSAGE_STYLE equals uppercase . The response object should either be {"message": "Hello json"} or {"message": "HELLO JSON"} , depending on the MESSAGE_STYLE value.