Senior Full Stack Engineer

Role Overview

• Drive Technical Leadership through Execution: Alongside Principal Engineers, you will lead and ship high-impact improvements across Rosso workflows, improving correctness, operability and scalability as volume and complexity grow.
• Drive Multi-Team Initiatives: Lead complex, cross-functional efforts across teams and systems
• aligning stakeholders and delivering high-leverage outcomes.
• Build & Ship: Continue being deeply hands-on in designing, coding, and reviewing critical components across stateful backend services, APIs, and infrastructure.
• Strengthen Foundations: Improve reliability and operability, observability, testing strategy, and deployment practices
• driving monitoring of service objectives, incident reduction, and operational excellence.
• Integrate machine learning models into production: Partner with ML/Data teams to productionise a range of models (including forecasting, optimisation and pricing) safely and effectively within core Rosso workflows.
• Design for correctness in complex workflows: Build and evolve pricing and deal-flow workflows where consistency and failure handling are first-class concerns.
• Prevent domain drift: Create and maintain clear domain boundaries, shared language, and reduce compounding complexity over time.
• Multiply Impact: Mentor Staff and Senior Engineers, raise engineering standards, and act as a trusted technical advisor to leadership.
• Plan for Scale: Architect systems to handle high-volume quoting/pricing activity and large customer counts, anticipating bottlenecks before they emerge.

Requirements

• Exceptional technical leadership experience: Experience operating at Staff+ or Senior Staff level, with clear evidence of organisation-wide impact at a high-growth startup.
• Architectural depth: Proven ability to design and evolve complex, stateful distributed systems spanning APIs, event-driven architectures, data systems, and front-end applications
• where domain logic is the primary source of complexity. Proven patterns for high-throughput performance and scaling architecture to support hundreds of thousands of customers, while preventing domain drift.
• Multi-team influence: Experience leading cross-team initiatives that directly impact revenue across engineering, product, data, machine learning, commercial and ops stakeholders.
• Modern tech expertise: Deep experience with:
• Python
• AWS serverless architecture (Lambda, API Gateway, DynamoDB)
• Event-driven systems and asynchronous workflows
• Data + domain modelling strength: Strong ability in data modelling for complex, interdependent business rules, including correctness, consistency, and designing for failure modes.
• Product & business alignment: Demonstrated ability to connect technical decisions to business outcomes and customer experience.
• First-principles problem solving: Ability to reason from fundamentals (constraints, incentives, data and system behaviour) to design solutions in complex, high-stakes domains.
• Navigating ambiguity: Comfort operating in evolving environments, defining direction where it doesn’t yet exist.
• Desirable: Experience in high-performance / high-scale environments (bonus if you’ve used tools like Kubernetes, Spark, or similar).
• Delivered a large, complex initiative end-to-end (greenfield or major redesign) with clear business impact.
• Experience scaling systems from early product-market fit to multi-product platforms
• Experience working closely or as part of Machine Learning teams
• Exposure to regulated industries (e.g., energy, fintech, govtech)
• Familiarity with real-time pricing engines, workflow orchestration, or AI/agentic systems
• Experience improving engineering org design, team topology, or platform strategy

Tech Stack

• AWS
• Distributed Systems
• DynamoDB
• Kubernetes
• Python
• Spark

Benefits

• Competitive salary
• our current band for this role is £129,500 or equivalent in local currency.
• Stock Options
• everyone on the team has ownership in our mission.
• 25 days holiday + public holidays
• Swap public holidays for ones that matter most to you. Plus, get an extra day off for your birthday 🎉.
• Remote & flexible working
• We’re fully remote with clear core hours, and no internal meetings on Friday afternoons.
• Home working & wellbeing budgets:
• Up to £1,200 / €1,200 annually to upgrade your remote setup (co-working passes, equipment, etc.).
• Up to £150 / €150 monthly on anything that supports your wellbeing
• from therapy to gym memberships to meditation apps.