Backend Software Engineer (Remoto) in London

Build AI-powered product capabilities that automate, predict, and simplify user workflows. Spendesk is looking for a Backend Software Engineer (IC3) to join our AI & Data Products squad and help build the next generation of product features powered by AI, ML, and intelligent automation. This is a hands-on backend role focused on turning predictive models, LLM capabilities, and business intelligence into real product experiences. You will work on backend services, APIs and MCPs that bring automation, prediction, and assisted decision-making into Spendesk’s user journeys, helping reduce manual work and make our product more proactive and intelligent.

You will collaborate closely with the 3 ML Engineers in the squad, as well as Product Managers, Designers, and applicative squads across Spendesk. Together, you will build production-grade services that expose ML-driven and LLM-driven capabilities in ways that are reliable, observable, and valuable for end users.

About the role

As a Backend Software Engineer (IC3) in the AI & Data Products squad, you will design, build, and operate backend services that power AI-native and ML-native product features. Your mission is to help Spendesk move from isolated intelligence components to real, user-facing product capabilities. In practice, this means partnering with ML Engineers to productionize predictive logic, expose it through clean APIs and services, and integrate it into workflows that automate tasks, simplify decision-making, or anticipate user needs.

You may work on features such as:

• automated categorization and enrichment of spend-related workflows,
• predictive assistance in finance or accounting journeys,
• intelligent recommendations based on historical behavior or contextual signals,
• LLM-powered experiences that simplify user actions and reduce friction,
• backend services that make AI capabilities reusable across multiple product flows.

This role requires both strong backend engineering and genuine interest in AI-powered product design.

Our tech environment

You’ll operate in a modern engineering environment designed for both product delivery and AI integration:

• TypeScript
• Node.js for backend and banking applications
• React on the frontend
• PostgreSQL for data storage; Redis, SQS, and Kafka for jobs, queues, and event streaming
• Terraform to define infrastructure as code
• Kubernetes, Lambdas, and Step Functions to run our applications
• AWS as our cloud provider, including AWS Bedrock for LLM access
• GitHub Actions for CI

You do not need to be an ML engineer, but you must be comfortable integrating predictive or generative capabilities into backend systems and user-facing product workflows.

Key responsibilities

Backend services for AI and ML-powered product features:

• Design, build, and operate backend services and APIs that power AI-driven, ML-driven, or automation-heavy product capabilities.
• Translate predictive logic and AI outputs into reliable backend behaviors that can be consumed by user-facing product flows.
• Ensure features are designed for production, not just experimentation, with clear ownership of deployment, monitoring, and maintainability.

Productionization of ML and LLM capabilities:

• Partner closely with the squad’s ML Engineers to productionize predictive models and LLM-driven capabilities.
• Help define evaluation and monitoring patterns that make intelligent product behaviors measurable over time.
• Contribute to the engineering patterns that allow ML and AI capabilities to be reused across multiple product features.
• Build backend capabilities that help automate repetitive tasks, anticipate user needs, or simplify complex workflows.
• Work on product experiences where AI or ML can reduce manual effort, improve decision quality, or shorten time to value for users.
• Partner with Product and Design to turn ambiguous ideas into concrete backend implementations with measurable impact.
• Bring pragmatism to delivery, balancing experimentation speed with long-term maintainability and trust.
• Define and uphold standards around latency, resilience, failure handling, and cost efficiency for AI-powered services.
• Build with responsible data handling, security, and privacy by default, especially when features interact with sensitive financial workflows.
• Embrace a “you build it, you run it” mindset, owning the health and quality of what you ship.
• Work hand-in-hand with ML Engineers, Product Managers, and Designers to deliver AI-powered product capabilities end-to-end.
• Collaborate with applicative squads (or join them for a quarter) to integrate AI and ML services into existing user journeys and backend systems.
• Help define the technical interfaces and integration patterns that make intelligent services easier to adopt across the product.
• Share best practices in backend reliability, production readiness, and AI feature delivery across the engineering organization.

Technical & data skills

You have:

• Strong backend engineering skills with TypeScript / Node.js or adjacent technologies.
• Practical experience, or strong interest, in integrating predictive models, LLM APIs, or other AI capabilities into product backends.
• Familiarity with technologies such as Kafka, SQS, Step Functions, PostgreSQL, and modern observability practices.
• Product-minded, customer-focused, and motivated by building features that create visible value for end users.
• Comfortable working closely with ML Engineers and translating their outputs into durable product capabilities.
• Fluent in written and spoken English, our business language.
• Experience productionizing ML-backed features such as classification, recommendation, forecasting, or automation.
• Experience integrating LLM-backed capabilities into product workflows.
• Familiarity with evaluation patterns for AI-powered features.
• Experience in SaaS, fintech, or regulated environments.

If this role excites you and you believe you could contribute, we encourage you to apply.

How we work

AI-first, product-led: prototype fast, dogfooding, iterate based on data.

You build it, you run it: owning deployment, monitoring, and continuous improvements.

Collaboration by default: PM, Design, ML Engineering, and Backend Engineering work together toward outcomes.

Pragmatic engineering: we optimize for impact, not theoretical perfection.

What success looks like in your first 90 days

You’ve shipped or materially advanced a production-grade backend service powering an AI-driven or ML-driven product capability.

You’ve partnered effectively with one or more of the squad’s ML Engineers to turn predictive or generative logic into a reliable user-facing backend flow.

You’ve contributed to a reusable backend pattern that makes future AI-powered product features easier to build across Spendesk.

We’re primarily hiring in Paris, London or Barcelona with a flexible hybrid setup. Outstanding remote candidates may be considered, but this is not a remote-first role.

About Spendesk

Spendesk is the AI-powered spend management and procurement platform that transforms company spending. Trusted by thousands of companies, Spendesk supports over 200,000 users across brands such as Payfit, Accor, Welcome to the Jungle, Swile, Big Mamma, Malt and Yousign. With offices in the United Kingdom, France, Spain and Germany, Spendesk also puts community at the heart of its mission.

Flexible on-site and remote policy. Latest Apple equipment — the tools you need to excel. Access to Moka.care — for emotional and mental health wellbeing. Great office snacks — to fuel your day. A positive team to work with daily!

We also offer location-specific benefits tailored to each market, including health insurance, wellness allowances, commuter support, meal vouchers, and gym memberships — ensuring you're well supported wherever you're based.

Diversity & Inclusion

At Spendesk, we're committed to fostering an environment where all differences are encouraged, supported and celebrated. We're building our culture for everyone, with everyone.