Rentalink

Rentalink is a UK property lettings and agency management SaaS platform. Tenants browse listings, apply, book viewings, and sign agreements online, while letting agencies manage landlords, tenants, tenancies, rent schedules, receipts, landlord statements, maintenance, and compliance in one system. I architected and built the entire backend from scratch with NestJS, PostgreSQL, Prisma, and Redis: 42 modules and 530+ REST APIs, now in production for 4+ agencies managing 2,000+ properties. I also lead the frontend team and build parts of the Next.js app myself, including the AI assistant’s chat interface.

• –Architected and built the entire backend from scratch: 42 modules and 530+ REST APIs, in production for 4+ agencies managing 2,000+ properties.
• –Designed and shipped an AI assistant that answers business questions in plain English using LangGraph, text-to-SQL, and RAG with pgvector embeddings, running on OpenRouter and Ollama models. Scoped PostgreSQL roles, read-only views, and a fail-closed SQL validator keep each agency limited to its own data.
• –Built the AI assistant’s chat interface and other screens in the Next.js frontend.
• –Engineered a full rent accounting ledger: rent schedules, receipt allocation, deposits, fees, expenses, landlord statements, and arrears, including council-funded placements with mid-period rate changes, period splitting, and bulk payments.
• –Cut tenancy search response time by 89% (7.4s to 0.8s) and paginated listing time by 83% by restructuring Prisma queries, and moved tenant-property matching to PostGIS spatial SQL with GiST indexes.
• –Built the full lettings lifecycle: listings (including HMOs and individual rooms), applications, viewings, compliance tracking, maintenance with invoices, inventories, inspections, and messaging.
• –Implemented PDF e-signatures with SHA-256 document fingerprinting, bulk Excel/ZIP data migration for onboarding agencies, and automated email and push notifications.
• –Own the AWS deployment end to end: Docker, a GitHub Actions CI/CD pipeline, ECR, and EC2.
• –Lead 2 frontend developers and work with a UI/UX designer: plan features, define API contracts, and write integration guides for async handoff.