Senior Fullstack Engineer

WHY DEPT®? We are a Growth Invention company built to help the world’s most ambitious brands grow faster. Operating at the intersection of technology and marketing, we create what is next by pioneering ideas, acting fast, and moving further because standing still just is not in our DNA. We are drawn to people who stay curious, move with intent, and never stop inventing. Our culture runs on three values: better together, relentlessly curious, and get sh*t done. It is how we work, how we grow, and how we make things that matter. At DEPT®, you will find the freedom to explore, the space to collaborate, and the trust to make a real impact for our clients, for each other, and for the world we are helping to build. ABOUT THE ROLE We're looking for a Senior Software Engineer to play a central role in a large-scale platform re-architecture for a leading financial intelligence client. This isn't a lift-and-shift; it's a ground-up rebuild of a suite of products used across public finance and structured finance sectors, including portfolios, alerts, ratings tools, and sector-specific applications. The legacy platform (.NET, SQL Server, Solr, MongoDB) is being replaced with a modern cloud-native stack ( React and TypeScript (frontend), Node.js (backend services), AWS with Lambda (serverless compute), and PostgreSQL, and parity must be maintained throughout the transition. You'll be working across the full stack, with a strong emphasis on analytical thinking, sound architecture, and the ability to hold complexity across both old and new systems simultaneously. We are primarily focused on technical expertise in the new platform’s tech stack, but overall, the ability to clear up ambiguity, reverse engineer rules from existing code and persevere in unfamiliar technical environments is critical. WHAT YOU'LL DO Own and deliver workstreams across the full stack as the platform migration progresses, sector by sector Contribute to architectural decisions on the new platform — this is a re-architecture, not a rewrite Help maintain and extend the legacy platform while parity is being built on the new stack Work across a range of product areas: portfolios, alerts, ratings tools, and sector-specific applications Contribute to the migration from MS SQL Server to PostgreSQL and the deprecation of Solr Participate in technical design discussions and translate requirements into clear engineering tasks Proactively surface blockers, risks, and dependencies before they impact delivery Contribute to code quality through reviews and informal knowledge-sharing with teammates WHAT WE'RE LOOKING FOR 5+ years of experience delivering production software applications Strong full-stack capability across modern frontend (React, TypeScript) and backend (Node.js) technologies Solid understanding of relational databases — PostgreSQL experience preferred; SQL Server background useful Comfortable operating across legacy and modern stacks in parallel — you don't need everything to be greenfield An architectural mindset: you think in systems, not just features Strong analytical skills — this domain involves complex, interconnected financial data AWS experience, ideally including serverless patterns (Lambda) Proficient with GenAI coding tools as part of your everyday workflow Independently productive: owns workstreams, knows when to ask for help, doesn't spin wheels Experience with search platforms (Solr or similar) is a heavy plus .NET or legacy platform experience is a bonus during the transition period. WHAT DO WE OFFER? We enjoy spending time together, working closely with other local colleagues, and getting to know one another. Our Buenos Aires offices (Villa Crespo or Mar del Plata) are fully equipped with refreshments and great common spaces! Premium healthcare through OSDE for the employee and their immediate family members Mendel prepaid card with a monthly allowance for grocery purchases Monthly reimbursements for Wi-Fi/electricity expenses Monthly reimbursements…