Full Stack Software Engineer (AI)

The Company
Timeline is a financial technology company on a mission to help millions of people plan, invest for, and enjoy retirement with confidence. As a privately owned fast-growing fintech company providing Platform, MPS and financial planning solutions, we are well placed to disrupt the traditional financial services market.

Our technology cuts out unnecessary costs, inefficiencies and anxiety for financial advisers, while improving the long-term investment returns for their clients.

We are a remote-first company with team members in over 13 countries.  And given our diversity of thought, backgrounds and life experiences, we are constantly striving to celebrate individual uniqueness, while achieving our common mission. As a scaling, high-growth company, developing and adapting are the norm.  If you’re after a dynamic company where you will make a real difference, then read on!

Role & Responsibilities

We are looking for a Full Stack Software Engineer (AI) to join our global, remote-first Engineering team. The team works asynchronously in a Kanban-style workflow, collaborating closely with the Product team and the wider business.

You'll be working primarily on the AI surface of our product — the systems that turn LLMs into useful tools for financial advisers. That includes the chat agent that advisers use to query their books, AI-assisted meeting notes, and the Elm UI through which our users experience all of this. You'll help shape how these systems behave, scale, and evolve as we learn what advisers actually need from AI.

Our technology stack: 

• Backend: Elixir / Phoenix
• Frontend: Elm / Elm UI / JavaScript / HTML / CSS — we use Elm today and will continue to
• Mobile: Flutter (note-taker app)
• AI: AWS Bedrock + BAML (for LLM client abstraction); agent loops, tool calling, evals
  

What we value as a team:

• Simplicity
• Code quality
• Experimenting with new features/technologies
• Being customer/user-focused
• Continual learning
• Leveraging AI to build software — we actively explore agentic coding workflows to help engineers move faster while maintaining high code quality

Role Requirements

Absolute must-haves

• Based within +/- 3 GMT time zone — our HQ is in the UK
• At least 5 years' software development experience
• Proficiency in Elixir
• A solid understanding of web technologies
• Can write maintainable and robust code
• Enjoy writing tests
• Want to help design, implement, and launch major user-facing features
• A strong understanding of systems architecture and database design
• Provide feedback and code reviews to peers
• An eye for great products and can work effectively with engineers and designers to build them
• Proactive with communication and have no problem managing time as a remote employee
• Excitement about working with LLMs and comfort with non-determinism — designing for it, testing it, debugging it. Prior production AI experience is a strong plus, but we'll help you ramp if you bring the engineering chops.

Nice-to-haves

• Empathy for the problems that financial planners face in their day-to-day operations and a desire to solve those problems
• Experience building SaaS products
• Experience with Elm (or a willingness to pick it up)
• Experience building production features with LLM APIs — agent loops, tool calling, evals
• Experience with retrieval-augmented generation, vector databases, prompt engineering, or LLM observability
• Experience with Flutter, or extending AI features into mobile surfaces

The Package (will vary for contractors)

• Competitive salary, dependent on experience
• Non-contributory pension scheme
• 28 days holiday plus bank holidays
• Non-contractual bonus scheme
• Potential to join company option scheme
• Insurance plans
• Cost of relevant professional qualifications and memberships
• Hybrid working
• Flexible hours (depending on team requirements)
• Wellbeing support