Introduction

Auth setup is a necessary evil. Most official documentation is a maze designed to waste a builder's time. This isn't that.

This is a direct, unfiltered guide. No fluff, no broken premises. Just the critical steps to get your OAuth 2.0 credentials for the major platforms and move on. Don't just patch on a login system; build a solid foundation for user access. Let's get it done.

1. Google OAuth (6 Steps)

The baseline. Get this done first. Dashboard: https://console.developers.google.com/

1. New Project: Go to Google Cloud Console. Name it ImgSquash [Environment]. Create it.
2. Enable API: Navigate to APIs & Services → Library. Search for Google+ API and enable it.
3. Create OAuth Client: Go to APIs & Services → Credentials. Click + CREATE CREDENTIALS → OAuth 2.0 Client IDs. Choose Web application.
4. Set Redirect URIs:
   • Production: https://imgsquash.com/auth/callback
   • Staging: https://staging.imgsquash.com/auth/callback
   • Dev: http://localhost:3000/auth/callback
5. Configure Consent Screen: Set your App Name, Support Email, and the userinfo.email + userinfo.profile scopes.
6. Get Credentials:
   • GOOGLE_CLIENT_ID
   • GOOGLE_CLIENT_SECRET

2. GitHub OAuth (4 Steps)

For the builders. This one's easy. Dashboard: https://github.com/settings/developers

1. New OAuth App: Go to GitHub Developer Settings → OAuth Apps. Click New OAuth App.
2. App Details: Fill in your Application name, Homepage URL, and a description.
3. Callback URL: Set the Authorization callback URL for production, staging, and dev.
4. Get Credentials:
   • GITHUB_CLIENT_ID
   • GITHUB_CLIENT_SECRET

3. Apple Sign-In (8 Steps)

Apple's process is a broken model. You just have to push through it. Dashboard: https://developer.apple.com/account

1. Create App ID: In the Developer Console, create a new App ID. Description: ImgSquash Web App. Bundle ID: com.imgsquash.web.
2. Enable Sign In with Apple: Find the capability and check the box.
3. Create Service ID: Identifier: com.imgsquash.web.service.
4. Configure Service: Edit the Service ID, enable "Sign in with Apple" again, and add your domain (imgsquash.com).
5. Set Return URLs: Configure for production, staging, and dev.
6. Create Key: Go to Keys, create one, and enable "Sign in with Apple."
7. Generate Private Key: Download the .p8 file. Don't lose it. Note your Key ID and Team ID.
8. Generate Client Secret: This is a JWT you have to generate yourself.
   • APPLE_CLIENT_ID
   • APPLE_CLIENT_SECRET

4. Discord OAuth (4 Steps)

Simple. Direct. How it should be. Dashboard: https://discord.com/developers/applications

1. New Application: Create it and give it a name.
2. Configure OAuth2: Go to the OAuth2 tab and add your Redirects.
3. Set Scopes: Add bot, identify, email, guilds.
4. Get Credentials:
   • DISCORD_CLIENT_ID
   • DISCORD_CLIENT_SECRET

5. Twitter OAuth 2.0 (6 Steps)

They call their developer platform a "platform." Incredible. You have to apply for access and wait. Dashboard: https://developer.twitter.com/

1. Apply for Access: You need "Elevated" access. Expect to wait.
2. Create App: Once approved, create an app in the Developer Portal.
3. App Details: Set your Website URL and a description.
4. Set Permissions: Edit App permissions to Read to get email address access.
5. Callback URL: Set the type to Web App and add your callback URL.
6. Get API Keys:
   • TWITTER_CLIENT_ID
   • TWITTER_CLIENT_SECRET

6. Facebook & Instagram OAuth (Meta Platform)

Welcome to the Meta maze. One dashboard for both. Dashboard: https://developers.facebook.com/

1. Create App: My Apps → Create App. Type: Business.
2. Add Products: Set up Facebook Login and Instagram Basic Display.
3. Configure Redirect URIs: Add your callback URLs for all environments. This is required for both products.
4. App Review: You must request email and public_profile for Facebook and user_profile for Instagram. Submit for review.
5. Get Credentials:
   • FACEBOOK_CLIENT_ID / FACEBOOK_CLIENT_SECRET
   • INSTAGRAM_CLIENT_ID / INSTAGRAM_CLIENT_SECRET

Other Key Platforms

These are straightforward. No excuses.

• TikTok: (4 Steps) Go to the developer dashboard, create a Web App, set Redirect/Live URLs, and grab your credentials.
• Coinbase: (4 Steps) Go to OAuth Applications, create a new app, set details and permissions (wallet:accounts:read, wallet:user:read), and get your keys.

Conclusion

The foundation is laid. Now execute.

1. Plug these values into your environment files. No placeholders.
2. Test every single provider. One by one.
3. Build real error handling for failures.
4. Get the buttons on the frontend.

Lets. Keep. Building. Faster.