Kerb - Live Roadside Assistance With Real ETA

Acceptance Criteria

Live Map: done when operator location updates within 10 seconds of movement on driver screen. AI Triage: done when breakdown type is correctly classified for 90% of test descriptions. Escrow Payment: done when Stripe transfer releases only after driver confirms job completion. Operator Onboarding: done when new operator can sign up, upload insurance proof, and go live in under 10 minutes.

How to build it, step by step

1. Run 'npx create-next-app@latest kerb --typescript --app' and install dependencies: '@supabase/supabase-js', '@supabase/auth-helpers-nextjs', '@stripe/stripe-js', 'stripe', 'twilio', '@googlemaps/js-api-loader', '@anthropic-ai/sdk'. 2. In Supabase dashboard create tables: drivers (id, name, email, phone), operators (id, name, phone, stripe_account_id, insurance_doc_url, is_verified, is_on_call, current_lat, current_lng, service_radius_km), jobs (id, driver_id, operator_id, status ENUM breakdown_type, lat, lng, description, fixed_price_gbp, stripe_payment_intent_id, created_at), job_events (id, job_id, event_type, message, created_at). Enable Row Level Security — drivers read only their own jobs, operators read jobs within their service radius. 3. Enable Supabase Realtime on the operators table (current_lat, current_lng, is_on_call columns) and jobs table (status column). Test with supabase.channel('operators').on('postgres_changes') in a throwaway script before building UI. 4. Build POST /api/triage using the Anthropic SDK: accept { description: string }, send to claude-3-5-haiku with a system prompt listing job categories (flat_tyre, battery_jump, fuel_delivery, tow_required, unknown), return { job_type, urgency, recommended_action } as JSON. Test with 10 hardcoded descriptions before wiring to the form. 5. Build Stripe Connect operator onboarding: GET /api/stripe/connect/onboard creates a Stripe Connect Express account and returns an account_link.url — redirect operator there. GET /api/stripe/connect/callback handles return_url, marks operator as stripe_connected in Supabase. Test in Stripe test mode with a dummy UK operator account. 6. Build the driver breakdown form at app/breakdown/page.tsx: Google Maps pin drop using @googlemaps/js-api-loader, textarea for description, on submit POST to /api/triage then POST to /api/jobs which inserts a pending job row and queries operators where is_on_call=true and location within service_radius using Postgres ST_DWithin (enable PostGIS extension in Supabase). Return matched operator list with ETAs estimated via Google Maps Distance Matrix API. 7. Build the live operator map at app/job/[id]/page.tsx: subscribe to Supabase Realtime on the specific job row and the assigned operator's location columns, render operator marker moving on Google Maps JS API, show ETA countdown from Distance Matrix, update every 15 seconds via Realtime channel. 8. Build operator dashboard at app/operator/dashboard/page.tsx: on-call toggle updates operators.is_on_call in Supabase, incoming job card shows driver location on map and fixed price, accept button calls POST /api/jobs/[id]/accept which updates job status to accepted and creates a Stripe PaymentIntent with application_fee_amount set to 12% of the job price. 9. Add Twilio SMS via lib/twilio.ts: trigger SMS to operator on new nearby job (job created event from Supabase webhook -> Vercel serverless function -> twilio.messages.create), trigger SMS to driver on operator acceptance with name and ETA. Use Twilio Verify for driver phone verification at signup. 10. Add job completion and payment release: driver taps 'Job Complete' -> POST /api/jobs/[id]/complete -> stripe.paymentIntents.capture(paymentIntentId) releases funds minus 12% application fee to operator's Connect account. 11. Upload insurance documents to Cloudflare R2 using the S3-compatible API (@aws-sdk/client-s3 pointed at R2 endpoint) — store the R2 object URL in operators.insurance_doc_url. Mark operator as verified manually in Supabase dashboard for V1. 12. Configure Supabase Auth with Google OAuth for drivers and magic link email for operators. Apply RLS policies: operators can only update their own row, drivers can only read jobs they own. 13. Deploy to Vercel, set all env vars (SUPABASE_URL, SUPABASE_ANON_KEY, SUPABASE_SERVICE_ROLE_KEY, STRIPE_SECRET_KEY, STRIPE_WEBHOOK_SECRET, TWILIO_ACCOUNT_SID, TWILIO_AUTH_TOKEN, ANTHROPIC_API_KEY, GOOGLE_MAPS_API_KEY, R2_BUCKET credentials). Register Stripe webhook endpoint for payment_intent.succeeded and account.updated events. 14. Test end-to-end with two real phones: one as driver submitting a fake breakdown, one as operator accepting and completing — verify Stripe transfer appears in Connect dashboard and SMS fires at each step.