Senior Software Engineer (Python)

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.

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

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

This role offers a clear path into Staff or Lead Engineer positions

• Drive architectural decisions across multiple teams
• Own complex, cross-cutting AI systems

Benefits at Aveni. What you’ll love:

• Remote-first working across the UK
• 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)