Senior Backend Engineer

About Sax AI Sax AI is building AI agents for compliance in investment banks in London. Sax AI delivers superhuman KYC (Know Your Customer) with AI agents executing and human KYC officers overseeing. We help banks outsource their KYC, 10x faster and 10x cheaper.

What You'll Do Build and optimize AI agents for compliance workflows using Python and LLMs Integrate with external data providers and with banks' internal systems Architect async task pipelines for complex, long-running compliance checks Develop APIs for the front-end application Contribute to architectural decisions that enhance system performance and reliability Write clean, maintainable, strictly-typed code that meets enterprise security and compliance standards

Tech Stack Python with mypy, Django, Celery PostgreSQL with pgvector, Redis AWS, Docker LLMs: Claude, Gemini

Qualifications 3+ years building backend systems in Python Strong software design and architecture, and domain modeling Experience designing APIs and with async/background job processing patterns Strong problem-solving abilities and systematic debugging approach Care about code quality, testing, and maintainability Bachelor's degree in Computer Science, Engineering or related field

Nice to Have Experience building enterprise SaaS applications DevOps experience: Terraform, AWS, infrastructure-as-code, CI/CD pipelines Financial services, KYC/AML, or regulatory compliance domain knowledge Experience with agentic AI systems, document processing/OCR pipelines

What Makes This Role Interesting Build AI agents that automate days of analyst work into minutes, in a high-stakes financial domain Work directly with investment banks on real compliance workflows Shape the architecture of a complex AI system in a fast-growing startup with enterprise clients A competitive salary with generous Stock Options.