Maydon Rent

A rental product needs the lease, the documents, the money and the people to agree with each other at all times. Splitting that across services early buys distribution problems before there is any distribution to justify them — but leaving it as one undifferentiated application makes every later change risky.

A modular monolith with clear boundaries, and four services written from scratch.

• —Identity service: role-based access control, thin JWTs, Redis-backed sessions and multi-account access.
• —Real-estate management service.
• —Listing marketplace.
• —Notification service.
• —Lease and contract workflows: digital signing, PDF generation, idempotent invoicing and resilient webhooks.
• —Asynchronous workflows on MediatR pipelines with a transactional outbox, so nothing publishes unless the transaction commits.

This is the codebase where I worked out how to use AI properly. Claude Code drafted, I owned the architecture, the security model and the review. Every suggestion went through the same tests and pipeline as anything hand-written — the failure mode is not bad code, it is plausible code nobody thought about carefully.