Who we are

The role 

Collaborating closely with our dynamic team of product designers and engineers, you will play a pivotal role in shaping the foundation of frontend at Helsing. Embracing a hands-on approach, you'll not only lead by example, but also spearhead the development and expansion of a tight-knit team that works across a wide-range of internal teams and products. Your primary emphasis will be on enhancing usability, creating re-usable foundations for multiple front-ends and optimising the end-user experience across the entire company.

The day-to-day

• Review code contributions, proposals, and RFCs from colleagues. At Helsing we strongly believe that unblocking others takes precedence over spending more time on your own work.

• Own the user interface end-to-end, from early wireframes and prototypes through to performant, production-ready code. You'll work closely with product and UX colleagues to shape how users interact with our tools. We have relatively few frontend engineers at Helsing; this means that we operate at a high level of autonomy and there are plenty of opportunities for impactful work.

• Propose and implement new features, capabilities, tooling, visualizations, or even full products across our stack. We encourage our engineers to look beyond their immediate team for missed opportunities, and to speak up when they identify one.

• Establish and evolve our React component library, ensuring consistency, reusability, and alignment with our visual design standards across multiple front-ends.

• Collaborate with others beyond your team and share knowledge with the wider frontend community at Helsing. Contribute to establishing our frontend engineering standards. Build or adopt tools that help enforce these standards, or make our frontend engineers more efficient in a different way.

• Become a mentor, find a mentee, and help support and develop our interviewing pipeline. The people make or break the company, and we want as many engineers as possible to be part of fostering and growing the organisation.

• Share your experience and technical know-how with other Helsingers. We host tech talks, get together for smaller "let's learn together" groups, run topical office hours or reading groups (e.g., on React or TypeScript), etc. to help each other get better with time.

• Connect with, understand, and make changes to backend systems as needed. Our backends are primarily written in Rust, and you'll need to be comfortable navigating unfamiliar codebases to unblock yourself and improve integrations. Rust experience is not a prerequisite to this role, though - you can learn that over time as needed.

• Present your work at our weekly demo sessions. We want engineers to come together around what they are working on and to feel like they are not endlessly squirrelling away at something that doesn't matter. To that end, we host (and actively work towards) demo sessions that allow early feedback, celebration of progress, and a better shared understanding of everything that goes on at Helsing.

You should apply if you

• Can write legible, maintainable, and performant frontend code - ideally using TypeScript and React.

• Are experienced with APIs and server-client communication like REST and GraphQL.

• Have experience with running a live production software.

• Are passionate about staying on top of current development best practices, libraries and frameworks.

• Are comfortable working with unfamiliar backends, ideally with some exposure to languages like Rust.

• Communicate well in English, both verbally and in writing.

• Enjoy collaborating with others, including reviewing code and pair programming.

• Are comfortable working asynchronously (writing PRs and RFCs, having discussions by email).

• Strive to improve yourself, your peers, and the culture you work in over time.

• Feel like ethical considerations are an inherent part of engineering.

Note: We operate at an intersection where women, as well as other minority groups, are systematically under-represented. We encourage you to apply even if you don’t meet all the listed qualifications; ability and impact cannot be summarised in a few bullet points.

Join Helsing and work with world-leading experts in their fields 

• Helsing’s work is important. You’ll be directly contributing to the protection of democratic countries while balancing both ethical and geopolitical concerns

• The work is unique. We operate in a domain that has highly unusual technical requirements and constraints, and where robustness, safety, and ethical considerations are vital. You will face unique Engineering and AI challenges that make a meaningful impact in the world

• Our work frequently takes us right up to the state of the art in technical innovation, be it reinforcement learning, distributed systems, generative AI, or deployment infrastructure. The defence industry is entering the most exciting phase of the technological development curve. Advances in our field of world are not incremental: Helsing is part of, and often leading, historic leaps forward

• In our domain, success is a matter of order-of-magnitude improvements and novel capabilities. This means we take bets, aim high, and focus on big opportunities. Despite being a relatively young company, Helsing has already been selected for multiple significant government contracts

• We actively encourage healthy, proactive, and diverse debate internally about what we do and how we choose to do it. Teams and individual engineers are trusted (and encouraged) to practise responsible autonomy and critical thinking, and to focus on outcomes, not conformity. At Helsing you will have a say in how we (and you!) work, the opportunity to engage on what does and doesn’t work, and to take ownership of aspects of our culture that you care deeply about

Nice to have

• Significant recent experience with React.

• Familiarity with backend interface tools like REST, GraphQL, gRPC/Protocol Buffers.

• Established understanding of modern JS bundlers, such as Vite, and experience maintaining frontend infrastructure.

• Experience with styling utility-class libraries such as TailwindCSS and building reusable React component libraries.

• Data visualization expertise (e.g., D3.js, custom charting, or complex dashboard design).

• Background in designing software for aerospace, defense, or AI end users.

What we offer

• A focus on outcomes, not time-tracking

• Competitive compensation and VSOP options

• Relocation support

• Social and education allowances

• Regular company events and all-hands to bring together employees as one team across Europe

• A hands-on onboarding program (affectionately labelled “Infraduction”), in which you will be building tooling and applications to be used across the company. This is your opportunity to learn our tech stack, explore the company, and learn how we get things done - all whilst working with other engineering teams from day one 

Helsing is an equal opportunities employer. We are committed to equal employment opportunity regardless of race, religion, sexual orientation, age, marital status, disability or gender identity. Please do not submit personal data revealing racial or ethnic origin, political opinions, religious or philosophical beliefs, trade union membership, data concerning your health, or data concerning your sexual orientation.

The role

Mentimeter is looking for a Product / AI Engineer to join our Recommendation Engine team and play a key role in shaping how AI creates value across our product.

We have multiple AI-powered features live in production, including a multi-agent system serving real users at scale. The work spans LLM orchestration, structured output generation, chained analysis pipelines, prompt engineering, and evaluation. Going forward, the technical challenges deepen: richer context management across sessions, more sophisticated agent architectures, personalization and relevance at scale, and the extension of AI capabilities across the broader Mentimeter product.

Over 300 million people have used Mentimeter to run interactive sessions - gathering input, running polls, and collecting feedback. We're building the AI-powered system that helps users get more value from those interactions: understanding what they learned, deciding what to do next, and acting on it.

You'll have a genuine chance to influence Mentimeter's medium- and long-term AI strategy.

The team

The Recommendation Engine team builds AI-powered recommendations that help Mentimeter users turn what they learn into what they do next - not just once, but across sessions and over time. The system gets smarter as it accumulates context: user goals, past interactions, and what's worked before. The ambition is to support users through ongoing processes, not just individual moments.

Together with our sister team, Results, we form the Insights area, where AI is a core part of how we build product experiences. We're a full product team: a product manager, a product designer, an engineering manager, and engineers. We work closely and partner up with other product teams across Mentimeter, but we also own end-to-end user experiences in our own right.

The work shifts between modes - running experiments to learn what creates value, and building the features, systems, and experiences that deliver it. If you enjoy shaping product direction as much as writing code, and can move between exploration and execution, you'll fit in here.

What you'll do

• Design, build, and improve LLM-powered features that create real value for users
• Work on multi-agent architectures, orchestration, and context management in the service of real user goals
• Build evaluation and quality systems for AI features
• Make model selection, cost, and latency trade-offs for production AI systems
• Leverage user interaction data to inform and improve AI-powered features - from exploratory analysis to production pipelines
• Explore emerging AI capabilities and assess where they add real value versus where simpler solutions win
• Act as a central figure of applied AI expertise within the team and the broader engineering organization
• Stay current with a fast-moving field and bring what you learn back to the team

Who you are

You have genuine enthusiasm for building AI-driven products and have shipped LLM-powered work into live environments, where user behavior, cost, latency, and failure modes were part of the job. Your background might be in software engineering, data science, ML engineering, or something else entirely – what matters is that you combine solid judgment on LLMs and data with a product-centric approach and ship product experiences that users value.

You’re comfortable navigating uncertainty in a rapidly developing space, and you have a track record of tackling complex technical challenges. We’re especially interested in LLM work that reached production or sustained real use – commercial products, internal platforms with serious adoption, or open-source with a clear quality bar – and we’re open to other paths if you can show depth (what you owned, how you measured quality, what failed in the wild).

You think about what to build as well as how to build it. You communicate clearly, simplify complex technical concepts, and share ownership of outcomes with the rest of the team. You're comfortable working across team boundaries - liaising with other product teams, thinking about broader architectural needs, and representing AI expertise in cross-team discussions.

We don’t optimize for a specific number of years on a CV – careers aren’t linear. What we do need is seniority in the type and depth of experience. With that said, this is not an entry-level role – we’re hiring someone who can contribute at a senior level from early on.

It's a big plus if you have

• Experience with LLMs in production at scale - real traffic, real cost constraints, real failure modes, not just prototypes or side projects
• Experience building AI features where evaluation was a genuine challenge - designing evals for non-deterministic outputs, understanding where your system fails, measuring quality over time
• Experience working on a user-facing SaaS product - you understand subscription dynamics, product-led growth, and what it means to ship to paying customers
• An NLP or text analysis or applied data science background - the team works heavily with text: session responses, generated insights, structured recommendations
• Experience working across multiple languages or parts of the stack - the work here spans Python, Ruby, and TypeScript, and we value people who are comfortable learning what they don't already know

Not required

Swedish is not required - daily work is carried out in English, and the Mentimeter team currently boasts over 50 nationalities. A college degree is not strictly required.

Practical information

This is a hybrid/on-site role at Mentimeter HQ in Stockholm, where we expect you to be in the office at least 3 days/week.
Please note that we do not offer relocation sponsorship for the position.

Recruitment process

1. Introduction call
2. Culture interview, onsite if possible
3. Technical competence interview - a technical system design case with other engineers, onsite