Supabase Auth + Storage + Realtime Core

Overview

Implement the three pillars that turn a Supabase database into a full application backend: user authentication (email/password, OAuth, magic links, session lifecycle), file storage (uploads, downloads, signed URLs, bucket-level RLS policies), and real-time subscriptions (Postgres change events, client-to-client broadcast, presence tracking). Every operation integrates with Row-Level Security through auth.uid().

Each pillar below carries a lean skeleton in this file; the full, copy-paste walkthroughs live in references/ so this file stays scannable.

Prerequisites

• Supabase project created at supabase.com/dashboard
• @supabase/supabase-js v2 installed (npm install @supabase/supabase-js)
• SUPABASE_URL and SUPABASE_ANON_KEY available from project Settings > API
• For Python: pip install supabase (wraps postgrest-py, gotrue-py, storage3, realtime-py)

Instructions

Read the file (Read), edit or create the client and route/component code (Write, Edit), and grep the project (Grep) to reuse an existing Supabase client before creating a new one. Use Bash(npm:*) to install the SDK and Bash(supabase:*) to run migrations/policies.

Step 1: Auth — registration, login, OAuth