Custom E-Commerce Support Platform

I want to give our online store an in-house customer-service platform that mirrors the flexibility of Five9 but is fully owned and hosted on a dedicated subdomain (e.g., cs.ourstore.com). Phase one must cover live chat and email; the voice channel only needs its framework prepared so we can plug SIP or WebRTC calling in later without rebuilding the core.

Chat
• Agents need a completely configurable widget: colours, branding, agent avatars, business-hour rules, proactive prompts, custom event triggers, macros, and tag-based routing.
• Real-time dashboards and historical analytics should be part of the same interface—no separate logins.

Email
• Automated responses tied to simple rules (new ticket, status change, etc.).
• A template library we can edit with variables like {{customer_name}}.
• Native open / click tracking surfaced in the agent timeline.

Voice (future-ready)
Just expose the endpoints, database schema, and permission model so we can later bolt on call routing, IVR, or recording without breaking existing data relations.

Core expectations
• Single sign-on for internal staff (OAuth or SAML is fine).
• Role-based access to queues and analytics.
• REST or GraphQL API documented for potential storefront or ERP hooks.
• Fully responsive UI—agents often work on 13-inch laptops.
• Code handed over in a private repo plus install/run documentation.
• Deployment to our chosen cloud provider on the subdomain; SSL and basic hardening included.

I’m happy to discuss tech stacks, but lean toward something that scales (Node, Python, or Go on the back end; React or Vue front end). Let me know your preferred approach, similar projects you’ve shipped, and an estimated timeline from kickoff to production.