You don't need to add it to a file in the codebase. In v0, environment variables are added through the Vars section in the in-chat sidebar:

Steps:

1. Look at the left side of your screen where you're chatting with me
2. You should see tabs like "Design", "Rules", "Vars", "Settings"
3. Click on the "Vars" tab
4. Click "Add Variable"

5. Enter:

   • Key: NEXT_PUBLIC_CONTRACT_ADDRESS
   • Value: 0xD5f4B2522FE77d07a576a9f0FAED3aD748F83d02
6. Click Save

That's it! The environment variable will be automatically available to your app. You don't need to create any .env files or modify any code files.

If you still can't find the Vars section, let me know and I can help troubleshoot!

Great question! Here's how it works:

Environment Variables in v0:

• The environment variables you set in the Vars section are stored in v0, not in your codebase
• They're NOT committed to GitHub (which is actually a security best practice)
• Your code references them as process.env.NEXT_PUBLIC_CONTRACT_ADDRESS, but the actual values don't live in files

When Publishing to GitHub:

1. Your code will be pushed without the actual env values (safe!)
2. Anyone who clones your repo will need to set their own environment variables

When Deploying (e.g., to Vercel):

1. Go to your Vercel project settings

2. Add the same environment variables there:

   • NEXT_PUBLIC_CONTRACT_ADDRESS = 0xD5f4B2522FE77d07a576a9f0FAED3aD748F83d02
   • NEXT_PUBLIC_GENLAYER_NETWORK = studionet
   • NEXT_PUBLIC_GENLAYER_CHAIN_ID = 61999
   • NEXT_PUBLIC_GENLAYER_RPC_URL = https://studio.genlayer.com/api
3. Vercel will inject these at build time

Best Practice: You can create a .env.example file in your repo showing which env vars are needed, but WITHOUT the actual values. This helps other developers know what to set up.

Would you like me to create a .env.example file for reference?