Senior Full Stack Developer (React + Node.js) to Build an Internal Clay Alternative

We're looking for an experienced full-stack developer to build a custom internal platform similar to Clay.com that will become the backbone of our lead generation and outbound marketing operations. This is not a WordPress project or a simple CRM. We're building a SaaS-style web application for internal use with room to expand into a commercial product in the future. Overview Our agency currently uses Clay.com for lead enrichment and AI-powered personalization, but we want to own our technology stack, eliminate credit limitations, and create workflows tailored to our business. We're looking for someone who has built complex web applications and is comfortable designing scalable architecture. Core Features Lead Management Company database Contact database Import from CSV Duplicate detection Search & filtering Custom fields Tags Data Enrichment Website scraping Company information extraction AI-generated company summaries Contact enrichment Industry classification Employee count Location detection AI Features OpenAI integration Personalized cold email generation AI company summaries AI lead scoring Custom prompt templates Website Analysis Crawl company websites Extract services Identify technologies used Detect marketing opportunities Analyze SEO basics Store structured website data Workflow Automation Build customizable workflows Queue jobs Background processing Scheduled enrichment Retry failed jobs Activity logs Email Integration Gmail / Google Workspace Outlook (future) Email verification API integration Export to sending platforms Email history Dashboard Lead statistics Processing queue Workflow monitoring Team activity API usage Analytics User Management Multiple users Roles & permissions Team workspaces Audit logs Tech Stack (Preferred) Frontend React Next.js TypeScript Tailwind CSS Backend Node.js Express or NestJS Database PostgreSQL Background Jobs BullMQ or similar Authentication JWT or Clerk/Auth.js Storage AWS S3 or equivalent AI OpenAI API Deployment Docker GitHub CI/CD Ideal Experience Please apply only if you have experience building products such as: CRM systems Marketing automation platforms SaaS dashboards Lead generation software Workflow automation tools AI-powered applications Large-scale internal business platforms Experience with scraping, APIs, queues, authentication, and scalable architecture is highly preferred. What We'd Like to See Please include: Links to similar SaaS applications you've built Your GitHub (if available) Your preferred architecture Your estimated timeline for an MVP Your hourly rate Any experience with AI, OpenAI, scraping, or marketing automation Project Scope This is expected to be a long-term project. Phase 1: Core database Lead management AI enrichment Website analysis Dashboard Phase 2: Workflow builder Team collaboration Advanced automation Additional integrations Phase 3: Continued improvements and new features We're looking for a developer who wants to become a long-term technical partner, not someone who is only interested in a quick one-off project.