Senior Software Engineer in Warrington

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 have continued to grow rapidly as adoption of AI in financial services accelerates, and we are 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

As a Software Engineer at Aveni, you will be responsible for building and scaling the products that sit on top of FinLLM (the UK's first LLM for the Financial Services industry) and other LLMs, enabling financial institutions to adopt AI safely and effectively. You won't be expected to build or train the LLMs themselves, instead you will be engineering the platforms, services, user interfaces and integrations that bring those models to life in the hands of advisers, analysts and banking teams.

Your work will focus on:

• Designing and implementing robust event-driven microservices and APIs
• Building scalable, cloud-native systems on AWS
• Developing modern, responsive React front-ends
• Integrating LLM-powered capabilities into real-world workflows
• Collaborating closely with product and AI specialists to turn ideas into reliable, customer-ready features

What you will be working with

You should be comfortable with most of our core technologies:

• Node.js and TypeScript
• React and modern front-end tooling
• AWS (e.g., Lambda, ECS/Fargate, API Gateway, SQS/SNS, DynamoDB, RDS)
• NestJS or equivalent back-end frameworks
• Microservices and event-driven architectures

We also actively embrace AI coding assistants (such as Claude Code) to speed up development, improve code quality and reduce repetitive work — and we encourage engineers to use these tools effectively.

What we are looking for:

• Experience building production systems using Node.js / TypeScript
• Hands-on experience developing UIs with React
• Solid understanding of cloud-native engineering on AWS
• Experience with microservices, messaging patterns and distributed systems
• A commitment to clean code, testing, observability and operational excellence
• A proactive and motivated mindset — someone who wants to build, ship and iterate quickly
• Interest in AI-powered products and a drive to learn

Join Us in Making a Difference

At Aveni, we believe that diversity drives innovation. We are committed to building a team that reflects the diverse communities we serve and creating an inclusive workplace where everyone feels valued and empowered to contribute their best work. If you are passionate about leveraging technology to drive positive change and want to be part of a team that is shaping the future of financial services, we would love to hear from you. We know that some people are likely to only apply where they meet 100% of requirements, but we would like to hear from you anyway. Apply now to join us on our mission to transform the financial services industry through AI!

What we offer:

• A collaborative and innovative work environment
• Career growth opportunities towards Technical Lead and beyond
• Exposure to cutting-edge AI-first engineering practices
• 34 days holiday plus your birthday off
• Share options
• Remote and flexible working
• Life insurance
• Income protection
• Private health care
• Eyecare
• On-going career development and training
• Freebies and discounts
• Emotional wellbeing (Employee assistance programme provides access to 24/7 employee counseling and emotional support)
• Cycle to work scheme
• Pension scheme (employer contribution matched up to 5%)

We are a remote-first company across the UK, with regular off-sites and in-person gatherings that are always fun, motivating and team-focused. If you want to build high-impact technology at the frontier of applied AI and help bring new products and intelligent agents to market, you will thrive here.