Associate Software Engineer (Python / Rust)

Location: Hybrid 2 days per week, based in WarsawSalary for Associate (IC1): • UoP (Contract of Employment) = 13,000 - 18,000 PLN per month gross • B2B = 15,000 - 21,000 PLN per month net +VAT 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 Until now, insurance has been making billion-dollar decisions using outdated tools.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. Your engineering responsibilities • 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 need to be successful • 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. Interview Process • Initial call with Talent team (30 minutes) • Manager Interview with Technical Assessment (90 minutes) • Values Interview with Tech Leadership (60 minutes) • Offer How hx Warsaw Works At hyperexponential, we believe in a balance between remote work, and building relationships across teams and locations. You’ll have your main office in Warsaw, 2 days a week, with also ability to travel to London HQ to meet the wider team. International travel will be much less frequent, perhaps 2-3 times a year. Warsaw HQ was established in 2023, quickly hiring our first handful of high-calibre engineers. Fast-forward to today in 2025, there are 50+ in Warsaw and surrounding cities who travel for the collaborative environment. On Wednesdays you’ll often find Warsaw HQ organising team lunch paid by hx, getting drinks after hours. The office is also dog-friendly, so feel free to bring yours along! What Your Offer Could Look Like B2B • Share Options at a highly successful Series B company • 25 days of non-working + Polish bank holidays • £5,000 GBP budget for Learning & Development • Mental Health Support and Therapy via Spectrum Life • Optional for you: access to Private Healthcare via 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 GBP budget for Learning & Development • 26 days of holiday + Polish bank holidays • Company pension • Company Sick Pay for 10 days at 100% salary • Mental Health Support and Therapy via Spectrum Life • Monthly Wellbeing allowance via Juno • Private Healthcare Insurance via Luxmed • Multisport - Classic level • Top-spec work equipment (MacOS, Windows + additional monitors, mechanical keyboards etc)