Senior Backend Engineer - Commercial Systems and Intelligence

About the team: The Commercial Systems and Intelligence squad is a newly formed team within SumUp's Acquisition Mission under the Run & Grow tribe. We sit at the intersection of data, backend engineering, and sales operations, building the infrastructure that powers how SumUp attributes merchant acquisition, calculates commissions, and understands the full lifecycle of every merchant. Today, these processes are largely manual. We're here to change that, automating what's opaque, and building systems that sales representatives, leadership, and analysts can actually trust. You'll join at the very beginning, helping to shape how the squad works, the architecture it builds on, and the standards it holds itself to.   What you'll do: Aggregating data from across the SumUp ecosystem to determine which acquisition channel or sales agent drove a merchant to take a valuable action (e.g. signing up, adopting a product) Establishing data models, API contracts, and rule definitions that automate existing manual commission workflows for field and tele-sales agents, partnerships and merchant referrals Build the Lifecycle Event Log in close collaboration with the Merchant Intelligence squad. A centralized store of curated merchant lifecycle events (signups, product usage, verification, purchases) used across attribution, recommendations, customer support and sales Build internal backoffices and APIs for sales representatives and leaders to monitor commission and modify commission plans, manage portfolios and resolve disputes Define and document API contracts, schemas, and integration patterns that other engineering teams can adopt confidently Establish best practices for testing, observability, and incident response within a newly formed squad Use AI and agentic coding tools deliberately, to scaffold services, write tests, explore unfamiliar code, and draft documentation while maintaining full accountability for what gets shipped   You'll be great for this role if y