Associate Software Engineer (Python & Rust) at Hyperexponential

ABOUT HYPEREXPONENTIAL (HX) At hyperexponential, we're building the AI-powered platform that enables the world's most critical decisions in a $7 trillion industry, which risks to take, and how to price them. These are the decisions that shape real-world outcomes: whether rockets successfully launch into space, autonomous vehicles make it to market, or communities recover after major storms. Until now, insurance has been making billion-dollar decisions using outdated tools. We're changing that. Our platform brings together data, AI, and human expertise to give insurers the fastest path from submission to decision - helping them move faster, act smarter, and take on more risk with confidence. Backed by a16z, Highland Europe, and Battery Ventures, we're scaling globally - already trusted by nearly 50 of the world's largest insurers, with zero churn and billions in premiums flowing through hx. What began as a single product in one market has rapidly evolved into a multi-product, multi-territory platform powering every stage of pricing and underwriting. AI is at the core of what we do - from building the world's first domain-specific AI peer programmer for insurance (think GitHub Copilot with a PhD in actuarial science) to shaping agentic workflows that reinvent how this industry operates. What makes hx different is the people who build it. Here, impact isn't tied to title or tenure; it's defined by the challenges you take on and the discipline you bring. Surrounded by peers who stretch you, you'll do the best, hardest work of your life in a company engineered to endure. If that sounds like you, join us in building what comes next. ABOUT THE KERNEL TEAM The Kernel team sits at the core of hx’s platform, responsible for the execution engine that runs pricing models safely, reliably, and at scale. Their work underpins the decisions insurers make using hx, ensuring complex pricing logic executes consistently while maintaining the performance and reliability required for mission critical underwriting workflows. Within this space, the team builds and maintains the systems that interpret, execute, and validate model logic. This includes improving the safety and determinism of execution, strengthening automated testing and verification, and developing tools that allow engineers and actuaries to trust the platform when deploying high value pricing models. In this role, you will support the Kernel team by contributing well scoped features, tests, and internal tooling while learning how the execution engine works end to end. You will work closely with experienced engineers to understand the architecture, investigate issues, and gradually take on more complex ownership as your understanding of the system grows. WHAT YOU’LL BE DOING - Implement small, well scoped backend improvements within the Kernel execution engine, delivering reliable changes that strengthen the stability and correctness of model execution. - Extend and maintain automated test suites that validate execution behaviour, increasing confidence in changes and helping the team maintain a high standard of safety in a critical system. - Contribute to internal tooling and scripts that support testing, debugging, and developer workflows, improving the speed and reliability with which the team can analyse Kernel behaviour. - Assist with structured debugging investigations by running defined scenarios, collecting logs and metrics, and summarising findings that help engineers identify root causes more quickly. - Learn the architecture and execution model of Kernel through hands on development and collaboration, steadily progressing from small tasks to more complex changes within the system. - Work closely with experienced engineers through reviews and pairing, contributing to a collaborative engineering culture while building the discipline required to operate safely in a high impact backend system. WHAT YOU’LL NEED TO HAVE DONE - Built backend components or services in Python, or a strongly typed compiled language such as Rust, Go, Java, Kotlin, C, or C++, delivering reliable functionality and maintainable code in production or academic systems. - Written automated tests for your own work, helping ensure changes behave as expected and maintaining confidence in system correctness as software evolves. - Applied core computer science fundamentals such as data structures and algorithms to implement efficient and reliable backend logic. - Investigated software issues by reproducing problems, gathering relevant logs or data, and clearly communicating observations and hypotheses to collaborators. - Collaborated effectively with other engineers through code reviews, pair programming, or mentorship, responding constructively to feedback and improving your work through iteration. - Demonstrated a strong learning mindset by picking up new technologies or languages, with enthusiasm to develop expertise in Rust and systems engineering over time. YOU’RE UNLIKELY TO THRIVE HERE IF - You prefer highly prescriptive work and feel uncomfortable operating in complex systems where understanding evolves through exploration and learning. - You prefer working in isolation rather than collaborating closely with teammates through reviews, pairing, and shared problem solving. - You are reluctant to seek feedback, ask questions, or take ownership of learning in a fast moving technical environment. - If reading our Culture Document [Upgrade to PRO to see link] leaves you feeling neutral rather than energised, hx may not be the place where you'll do your best work. We're building something that asks for commitment and conviction, and we want you to feel excited by the opportunity to grow with us. COMPENSATION At hx, we're committed to salary transparency. You'll always have clarity on pay early in the process - our Talent Partner will share details with you during initial conversations - and we're working towards publishing salary information for all roles globally. Because we're building at the intersection of technology/SaaS and insurance, our roles don't always map neatly onto traditional benchmarks. Our approach is to design compensation that's competitive in the market, fair across teams, and aligned with the impact our people make. Equity: We offer equity across all roles at hx, making it a significant component of total compensation. Your talent partner will be able to share more details about this. BENEFITS Depending on how you choose to join hx (B2B or UoP), your benefits can look like: B2B - Share Options at a highly successful Series B company - 25 days of non-working + 14 Polish bank holidays - £5,000 budget for Learning & Development - Mental Health Support and Therapy via Spectrum Life - Optional for you: access to Healthcare package provided by Luxmed + Multisport (fully funded by yourself as B2B Contractor) - Top-spec laptop (MacOS or Windows) Contract of employment (UoP) - Share Options at a highly successful Series B company - £5,000 budget for learning & development - 26 days of holiday + 14 Polish bank holidays - Company pension - 10 days company sick pay at 100% salary, thereafter in line with labour law - Mental health support and therapy via Spectrum Life [Upgrade to PRO to see link] - Monthly wellbeing allowance via Juno - Healthcare package provided by Luxmed - Multisport card at Classic level - Top-spec work equipment (MacOS / Windows + additional monitors, mechanical keyboards etc) ADDITIONAL PERKS - Top-spec equipment (laptop, screens, adjustable desks, etc.). - Regular remote and in-person hackathons, lunch and learns, socials, and game nights. - Team breakfasts and lunches, snacks, drinks fridge, and a fun office at The Brain Embassy [Upgrade to PRO to see link] - Exceptional opportunities for personal development and growth as we build something remarkable together. INTERVIEW PROCESS - Initial call with Talent team (30 minutes) - Manager Interview with Technical Assessment (90 minutes) - Values Interview with Tech Leadership (60 minutes) - Offer OUR COMMITMENT TO DIVERSITY hxer's are at the centre of everything we build. We know that progress depends on diverse perspectives, and we are committed to creating an environment where everyone can thrive, grow, and make an impact. We recognise there is always more to do, and we take responsibility for shaping a workplace that is not only diverse but genuinely inclusive. Diversity is not just the right thing to do, it is key to solving the complex challenges we choose to take on. By welcoming people from all backgrounds and experiences, we strengthen our ability to question assumptions, push boundaries, and design solutions that endure. If you're energised by complexity and motivated to grow, we encourage you to apply and join our global team. NEXT STEPS If this opportunity resonates with you, we encourage you to apply or share it with your connections! Our dedicated talent team reviews all applications, and we promise to provide feedback regardless of the outcome. For more information about applying and to view other opportunities, you can visit our careers page. Please note that background checks will be conducted as part of the hiring process to ensure compliance with our governance policies. We handle all background checks sensitively and in full compliance with relevant regulations. All applicant data will be processed in accordance with data protection regulations and our privacy policy.