Senior Software Engineer (Python)

Aveni is building next-generation AI systems for UK financial services, where safety, compliance, and trust are non-negotiable. We're hiring a Senior Software Engineer to work on AI and agentic platform capabilities that power intelligent, automated workflows for financial services. This is a high-impact role building foundational technology that underpins Aveni's AI-first strategy.

You'll work on systems that govern how AI agents behave in regulated financial contexts, designing and implementing policy enforcement, safety controls, behavioural monitoring, and evaluation frameworks. This work sits at the intersection of platform engineering, AI/ML systems, and compliance-by-design architecture. You'll be joining at a pivotal moment as Aveni scales from startup to enterprise-grade AI FinTech, working on problems that matter: making AI safe, auditable, and trustworthy in high-stakes financial environments.

What You’ll Be Doing

• Design and implement scalable Python services powering AI-driven workflows
• Develop resilient, observable systems with strong error handling and compliance traceability
• Work within a serverless, event-driven AWS architecture
• Take ownership of features from design through to production
• Collaborate with Product, AI Platform, and Compliance teams
• Contribute to sprint planning, estimation, and delivery
• Build intelligent workflows using LLMs and agentic architectures
• Integrate AI models into production systems
• Design guardrails, policy enforcement, and behavioural monitoring for AI agents
• Support and guide junior and mid-level engineers
• Lead code reviews and promote engineering best practices
• Contribute to documentation, demos, and knowledge sharing
• Use AI coding tools to accelerate development and improve quality
• Help define best practices for AI-assisted software engineering

What We’re Looking For

Must Have

• Strong Python expertise in production environments
• Experience building cloud-native systems on AWS (Lambda, DynamoDB, S3, EventBridge)
• Experience working with LLMs or AI/ML systems
• Strong understanding of APIs, async systems, and scalable architecture

Nice to Have

• Experience with AI safety, guardrails, or policy enforcement
• Background in agentic systems or autonomous workflows
• Experience in financial services or regulated environments
• Familiarity with Node.js / TypeScript, Terraform or CDK
• Knowledge of observability tools and ML fundamentals

You’ll Thrive If You Are

• Pragmatic and able to balance speed with long-term quality
• Curious about AI, especially safety and responsible usage
• Comfortable working in a fast-moving scale-up environment
• A strong communicator who can explain complex ideas clearly
• Passionate about mentoring and raising team standards