Senior Applied AI Engineer

Job Description

Are you a backend engineer who wants to build the agentic AI platform behind products used by millions of employees across Europe?

Are you interested in joining of Europe's fastest growing companies? Do you want to impact the wellbeing of millions of users?
If yes, join us to make an impact in a fast-paced and dynamic environment where you’ll play a key role in driving financial accountability, supporting strategic decisions, and enabling sustainable growth.
Epassi’s purpose is to boost everyday well-being. We are a leading provider of employee benefit solutions across Europe. We were established in Finland in 2007, and in 2008 we were the first company to launch a mobile-payable employee benefit payment solution in Europe. Since then, we have consistently grown, diversifying our products and introducing our services into new markets.
Epassi has been awarded by the Financial Times as one of the fastest-growing companies in Europe on multiple occasions.

Your mission at Epassi:

You will build Epassi's shared AI platform: the agentic loops, LLM integrations, and tool-calling infrastructure that every product team plugs into. Employees use our products to discover and use their benefits in natural language, and employers rely on them to understand how those benefits perform. Your job is to make those interactions reliable, grounded in real data, and reusable as a common capability across Epassi's products. This is a hands-on engineering role: you design, code, ship, and operate the platform yourself. Product teams across our European markets integrate what you ship.

Your responsibilities will be:

• Design and build agentic workflows on Amazon Bedrock: multi-step reasoning loops, tool calling, and orchestration of LLM calls with deterministic business logic.
• Build the tools agents call: search over benefits and merchant data, structured analytics queries over usage data, and integrations with internal services.
• Ground LLM outputs in real data with retrieval and structured queries, and make correctness measurable through automated evals.
• Ship the platform as a product for other engineers: clean APIs, SDKs or service contracts, versioning, and documentation that product teams can integrate without hand-holding.
• Implement guardrails for a fintech-adjacent domain: prompt injection defenses, PII handling, output validation, and cost and latency budgets.
• Own your services in production: observability, on-call readiness, and honest incident follow-up
• Work with product teams adopting the platform, gather their integration feedback, and feed it back into the roadmap.
• Review code and designs from peers and raise the bar on how the team builds with LLMs.

What you should bring:

• Experience: 5–8 years of backend engineering in Java or Python, with production services you have designed, shipped, and operated yourself.
• LLM integration in production: You have shipped at least one real LLM-powered feature or service: agent loops, function/tool calling, RAG, or structured output pipelines, and you can talk concretely about what broke and how you fixed it
• AWS and Bedrock: Solid AWS experience; hands-on Bedrock experience is a strong plus, and deep experience with another provider's API (Anthropic, OpenAI, Vertex) transfers
• Evals and quality: You test LLM behavior systematically: eval datasets, regression suites, and metrics.
• Platform mindset: You have built APIs or services consumed by other teams and you design for their developer experience, versioning, and backwards compatibility.
• Data grounding: Comfort with search (OpenSearch, vector stores) and structured data (SQL), because our agents answer from real benefits and usage data.
• AI-native development: You work AI-natively yourself: tools like Claude Code, Cursor, or Copilot are part of your daily workflow, and you hold AI-generated code to the same standard as your own.

Your language profile:

• Fluent in English (working language)

Why You Should Join Us

Epassi is one of Europe's fastest-growing employee benefits companies, serving millions of users across the Nordics, DACH, and Southern Europe. You will join at the moment we build our AI platform from the ground up: the agents you ship will power benefit discovery for employees and analytics for employers across every Epassi product. You get real ownership, a modern AWS-based stack, an AI-native engineering culture, and colleagues across Europe who care about shipping.