Hey @joseluisgalvis. Most people here use English as a common language, so you'll likely get more responses using that instead of Portuguese. I ran your original post through Google Translate so I could get an English version to share for increased visibility.

It seems that I am having problems moving forward with the deployment in Vercel. When trying to configure and launch my API project on Node/Express, connected to BBDD Online on Railway, I received the error: “Environment Variable ‘DB_HOST’ references Secret ‘db_host’, which does not exist.”

This occurs even after having configured the environment variables in the configuration section of my project. I tried to link the project and also deleted the .vercel directory, but the problem persists.

Thanks for sharing the repository. I see the vercel.json uses the legacy env option. We actually recommend against using that. Instead, you should define environment variables in the Project Settings.

The error will go away if you remove the env section from the vercel.json file and move the variables to the Environment Variables section of your project's settings.