Software Engineer (Rust)

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 Until now, insurance has been making billion-dollar decisions using outdated tools.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, building the execution engine that underpins how customer models are evaluated, validated, and run safely at scale. Their work directly enables hx Renew and future products to make correct, performant, and explainable decisions in high-stakes environments. Within the team, engineers work on deeply technical system problems spanning execution, concurrency, memory management, and observability. The focus is on building a robust, modular engine that can evolve over time without compromising correctness or performance. As a Software Engineer in the Kernel team, you will own meaningful parts of this critical system end to end, contributing production code, improving architecture, and partnering closely with adjacent teams to ensure the engine meets real product and customer needs. What you’ll be doing Designing and delivering backend features in the Kernel execution engine that improve correctness, performance, and reliability for customer model runs at scale. Strengthening a clean, modular Kernel architecture that is easy to understand, test, and safely evolve over time. Building automated tests and observability for complex execution scenarios, enabling faster detection, diagnosis, and resolution of production issues. Partnering with adjacent engineering teams to shape Kernel behaviour and interfaces, providing clear technical input and following through to delivery. Owning work from design through rollout and monitoring, balancing immediate product needs with long-term system sustainability. Demonstrating hx values by proactively identifying risks, collaborating constructively, and taking full accountability in a critical core-platform area. What you’ll need to have done Built and shipped backend systems in a polyglot production environment, working across languages such as Rust, Python, or C/C++, and choosing the right tool for the problem. Either used Rust in production systems, or demonstrated strong systems experience in C/C++ or Python with clear evidence of learning and adopting new languages quickly (you will be upskilled in Rust if you're not familiar). Delivered backend features where correctness, performance, and resource efficiency were critical, and improved systems based on real production behaviour. Applied solid systems thinking around execution, concurrency, and memory or resource management in real-world backend services. Designed and implemented effective testing and observability that made complex backend behaviour understandable, debuggable, and safe to evolve. Owned work end-to-end from design through rollout, monitoring, and iteration, collaborating closely with peers and raising risks early. You’re unlikely to thrive here if You prefer highly predictable work and feel uncomfortable operating in ambiguous, evolving problem spaces. You optimise for shipping quickly at the expense of correctness, maintainability, or long-term system health. You avoid ownership of outcomes beyond your immediate code changes. If reading our Culture Document 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, w