Senior Ai/Ml Engineer

Plum Fintech; England; Hybrid; GBP 90,000 - 150,000; Full time

Benefits offered by this job

Own part of the company through stock

Private health insurance

Annual training budget

Plum Premium for free

Flexible remote working: 2 days in the

25 days holiday + bank holidays

45 work-from-anywhere days

Sabbatical after 4 years

Enhanced parental leave

Volunteering day

Team trips

Job summary

Plum Fintech is expanding its AI Platform team in London, delivering foundational infrastructure and tooling for AI-powered products. You’ll own scalable backend systems, design internal libraries, and promote best practices in prompt engineering and guardrails across multiple squads.

The role demands 5+ years in software/ backend/ platform engineering, strong cloud and AI framework experience, and a passion for reliability, observability, and developer experience.

Qualifications

• 5+ years of software/backend/platform engineering experience.
• Experience designing scalable backend platforms for AI-powered products.
• Hands-on with AI frameworks and agentic architectures.
• Knowledge of cloud platforms (GCP/AWS/Azure).

Responsibilities

• Design and build scalable AI Platform infrastructure used by multiple product squads.
• Develop internal libraries, services, and tooling supporting AI initiatives.
• Define best practices for prompt engineering, AI guardrails, and evaluation.
• Ensure observability, cost efficiency, and reliability of the platform.
• Collaborate with product and engineering teams to drive adoption.

Skills

Backend engineering

AI frameworks

Cloud platforms

Observability

Infrastructure as code

LangChain / LangGraph

Tools

ADK

LangChain

GCP

Job description

Millions of people want to grow their money but don't know where to start. More than 90% of adults don’t access traditional financial advice. That's the gap Plum was built to close.

We're building the proactive money platform that makes it easy for people to smartly and sustainably grow their money. Whether you're stashing the cash for tea and toast in your first home or catching some rays during retirement, we've got your back.

Since 2016, millions of people across 10 European markets have set aside more than £10 billion with Plum. But what we're most excited about is what comes next and the opportunity for our people to help shape it.

We're now going after something even bigger: the £2 trillion+ advised market in the UK and beyond, currently locked behind high fees and complexity. By combining AI-driven financial guidance with the products people actually need, we're building a solution for everyone, not just the wealthy few.

At Plum, you'll be part of a team that's ambitious, curious and driven. We move fast, learn from what doesn't work, challenge the status quo and, most importantly, build something that makes people's lives better. We believe great ideas can come from anywhere, and that the best work happens when people feel trusted to take ownership, collaborate openly and bring their whole selves to work.

Join nearly 300 Plumsters and be part of a team shaping the future of money

The role:

As part of the AI Platform team, you will play a key role in building the foundational infrastructure, frameworks, and tooling that enable AI-powered products and capabilities across the organization. This role requires a high degree of autonomy and ownership, as you'll be responsible for designing scalable solutions that empower multiple engineering teams while ensuring reliability, observability, and cost efficiency.

What We're Looking For

• 5+ years of experience in Software Engineering, Backend Engineering, or Platform Engineering.
• Strong experience building and maintaining backend systems and distributed services in production environments.
• Experience designing developer platforms, internal tooling, shared services, or infrastructure that supports multiple engineering teams.
• Hands-on experience building AI-powered applications and services using modern LLM frameworks and agentic architectures.
• Good understanding of modern AI concepts and practices, including:
• Large Language Models (LLMs)
• Retrieval-Augmented Generation (RAG)
• Prompt Engineering
• AI Guardrails
• AI Evaluation Frameworks
• Experience with AI frameworks such as Agent Development Kit (ADK), LangChain, LangGraph, CrewAI, or similar.
• Experience working with cloud platforms such as Google Cloud Platform (preferred), AWS, or Azure.
• Strong understanding of system reliability, observability, monitoring, and incident management.
• Experience with Infrastructure as Code and cloud-native architectures.
• Previous experience working within a Platform Engineering team is a strong plus

Key responsibilities:

• Design, build, and maintain a robust, scalable, and cost-effective AI Platform that supports AI initiatives across the organization.
• Develop and maintain internal frameworks, libraries, and services used by multiple product squads.
• Establish and promote best practices around prompt engineering, AI guardrails, and AI evaluation methodologies.
• Build platform capabilities that enable teams to safely deploy, monitor, and iterate on AI-powered applications.
• Configure and maintain tracing, monitoring, observability, and incident management solutions to ensure platform reliability.
• Partner closely with product and engineering teams to understand their needs and provide scalable platform solutions.
• Continuously improve developer experience and platform adoption across the organization.

Tech Stack:

Backend

• Python
• FastAPI
• Agent Development Kit (ADK)

Datastores

• PostgreSQL
• BigQuery
• Firestore

Infrastructure

• Google Cloud Platform (GCP)
• RabbitMQ
• Terraform

Monitoring & Observability

• Grafana
• Prometheus
• Langfuse
• incident.io
• Sentry

Plum's Perks

• Own part of the company you're helping grow through stock options
• Private health insurance
• Annual training budget
• Plum Premium for free
• Competitive referral scheme
• Flexible approach to remote working: we encourage at least 2 days a week in one of our beautiful offices in London, Athens or Cyprus
• Team breakfasts and team lunches
• 25 days holiday + bank holidays
• 45 work-from-anywhere days to give you flexibility to work your way
• 2 weeks sabbatical after 4 years to take the break you deserve
• Enhanced parental leave
• 1 paid volunteering day annually
• Annual team trip to a surprise destination!
• A fun, inclusive company culture (think )

Thanks,

Plum Team

*Plum is an Equal Opportunity Employer. Plum does not discriminate on the basis of age, race, religion, sex, gender identity, sexual orientation, non-disqualifying physical or mental disability, national origin or any other basis covered by appropriate law. All employment is decided on the basis of qualifications, merit and business need