Senior Backend Developer (Python/Django)

Keylr is a London-based PropTech company building a modern B2B SaaS platform and marketplace for the property industry. Our platform enables property managers, estate agents, and service providers to manage operations, compliance, job scheduling, payments, and supplier networks from a single platform. A core part of our product is integrating with multiple third-party platforms, including payment providers, identity verification services, CRM systems, Property Management Systems (PMS), AI services, and other external APIs. We're building a highly connected platform where reliable integrations are fundamental to the product. The Role We're looking for an experienced Senior Backend Developer (Python/Django) to help build our SaaS platform from the ground up. You will work closely with our Full Stack Developer to design and develop scalable backend services, REST APIs, and the integrations that power the Keylr platform. This role is heavily focused on third-party API integrations. You should be confident working with external APIs, webhooks, authentication flows, background processing, and complex data synchronization between systems. Key Responsibilities ● Build and maintain backend services using Python and Django. ● Design secure, scalable REST APIs for our web and mobile applications. ● Develop and maintain integrations with third-party platforms including: ○ Stripe & Stripe Connect ○ TrustID ○ CRM platforms ○ Property Management Systems (PMS) ○ AI/LLM services ○ Other external APIs ● Build webhook processing and background jobs for reliable integrations. ● Design and optimize PostgreSQL databases. ● Implement secure authentication and authorization using JWT/OAuth. ● Work closely with the Full Stack Developer to deliver complete product features. ● Troubleshoot API integrations and ensure system reliability. What We're Looking For ● 4–6 years of backend development experience. ● Strong expertise in Python and Django. ● Proven experience designing and building REST APIs. ● Extensive experience integrating third-party APIs in production environments. ● Strong understanding of webhooks, OAuth, API authentication, and asynchronous processing. ● Experience with PostgreSQL, AWS, Docker, Git, and CI/CD. ● Ability to read API documentation, troubleshoot integration issues, and deliver reliable solutions. Highly Preferred ● Hands-on experience with Stripe Connect. ● Experience integrating TrustID, CRM platforms, Property Management Systems (Guesty, Hostaway, Arthur, Reapit, etc.), or other enterprise SaaS platforms. ● Experience integrating AI/LLM services. ● Experience building SaaS or marketplace products.