Staff Software Engineer, Martech

<div class="content-intro"><p>Flex is a growth-stage, NYC headquartered FinTech company that is building the payment layer for life's essential bills, giving households one place to see, split, and pay their bills around how they live and get paid. By offering greater choice over how and when payments are made and allowing eligible on time payments to help build a positive credit history, Flex puts households back in control of their cash flow.</p> <p>That work brings together people with different perspectives who challenge the status quo and take ownership of solving difficult problems. For you, that means doing the best work of your career next to people who make you better, and together bringing ideas to life that make a real impact for the people we serve.</p></div><p class="font-claude-response-body break-words whitespace-normal"><strong>About the role</strong></p> <p class="font-claude-response-body break-words whitespace-normal">Flex is looking for a Staff Software Engineer to join our MarTech (Marketing Technology) team. This role involves spearheading the implementation of the platforms, services, and customer-facing web experiences that power how Flex finds, wins, and keeps customers.</p> <p class="font-claude-response-body break-words whitespace-normal">MarTech is the connective layer between our ad platforms, website, messaging systems, analytics, and product data. We turn marketing spend into a measurable, repeatable growth engine, and give marketing the ability to launch, test, and personalize campaigns without hand-built engineering each time. It's a team with a broad surface area, owning growth engineering end to end across Lifecycle Marketing (email &amp; SMS), Performance Marketing (paid acquisition), Brand (social and every getflex.com property), and Product Marketing.</p> <p class="font-claude-response-body break-words whitespace-normal"><strong>Here are some of the projects and systems in MarTech you'll have opportunities to work on:</strong></p> <ul class="[li_&amp;]:mb-0 [li_&amp;]:mt-1 [li_&amp;]:gap-1 [&amp;:not(:last-child)_ul]:pb-1 [&amp;:not(:last-child)_ol]:pb-1 list-disc flex flex-col gap-1 pl-8 mb-3 print:block print:space-y-1"> <li class="font-claude-response-body whitespace-normal break-words pl-2">Incentive platform — event-driven credit assignment for referrals, affiliates, and campaigns.</li> <li class="font-claude-response-body whitespace-normal break-words pl-2">Attribution and measurement — conversion APIs, identity resolution, and spend/event pipelines behind our acquisition cost reporting.</li> <li class="font-claude-response-body whitespace-normal break-words pl-2">Customer-facing web — the full getflex.com surface area and paid-acquisitio