Senior Software Engineer (Python)

Job Description This is a remote position. Aveni is redefining how financial institutions use AI. We build real, production-ready agentic systems that reshape how banks, advisers and financial services firms operate, replacing fragmented processes with intelligent, end-to-end workflows. We have been recognised as Fintech of the Year for two consecutive years and awarded Best Specialist Technology Service at the Professional Adviser Awards 2025. Backed by leading investors including Puma Private Equity, and commercially supported by Lloyds Banking Group and Nationwide Building Society, we previously completed one of Scotland’s largest Series A rounds. Since then, we’ve continued to grow rapidly as adoption of AI in financial services accelerates, and we’re now scaling our engineering organisation to meet that demand. Our engineering team includes experienced software engineers and PhD-level AI specialists, with strong ties to the University of Edinburgh, giving you access to exceptional expertise and opportunities for continuous learning as part of the day-to-day work. The Role 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. Your work will focus on: 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 Build Production-Grade Systems 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 Own Delivery End-to-End Take ownership of features from design through to production Collaborate with Product, AI Platform, and Compliance teams Contribute to sprint planning, estimation, and delivery Shape AI & Agentic Systems Build intelligent workflows using LLMs and agentic architectures Integrate AI models into production systems Design guardrails, policy enforcement, and behavioural monitoring for AI agents Mentor & Elevate the Team Support and guide junior and mid-level engineers Lead code reviews and promote engineering best practices Contribute to documentation, demos, and knowledge sharing Drive AI-Augmented Engineering Use AI coding tools to accelerate development and improve quality Help define best practices for AI-assisted software engineering Requirements 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 Career Growth This role offers a clear path into Staff or Lead Engineer positions, where you’ll: Drive architectural decisions across multiple teams Own complex, cross-cutting AI systems Shape Aveni’s long-term AI platform strategy Benefits Join Us in Making a Difference At Aveni, we believe that diversity drives innovation. We’ve built our business to ensure an inclusive workplace where everyone feels valued and empowered to contribute their best work. If you’re passionate about technology and its ability to drive positive change for the future of financial services, we’d love to hear from you. Even if you don’t meet 100% of requirements, we’d like to hear from you anyway if you believe you’d fit in. Apply now to join us on our mission to transform the financial services industry through AI. Benefits at Aveni. What you’ll love: Remote-first working across the UK Work abroad policy Co-working spaces available 34 days holiday (including flexible bank holidays) and your birthday off Company-wide off-sites Optional Personal Development Plan Flexible benefits platform Protection essentials including Life Insurance, Income Protection, Critical Illness cover, and Pension (up to 5% matched employer contribution with optional increased contributions) Private health and dental care Potential share options Enhanced family leave