# Jeff Rosenberg > Software Engineer at Retool Location: New York, New York, United States Profile: https://flows.cv/jeffrosenberg Intellectually curious and analytic full-stack engineer. A quick learner who enjoys tackling challenging problems, creating original and innovative applications, and bringing simplicity to complex systems. Particularly experienced in React/Node TypeScript codebases, working with data-centric applications, operating in product/client-facing roles, and leading a variety of results-oriented projects and teams. Always looking to work with smart, good people. ## Work Experience ### Software Engineer @ Retool Jan 2025 – Present | New York City Metropolitan Area ### Software Engineer @ Libretto Jan 2024 – Jan 2025 | Brooklyn, New York, United States • Built and improved numerous LLM-driven systems, including LLM-as-Judge evaluations, Eval generation, Eval Grading and Calibration, and Test Case Generation • Performed various prompt engineering and model fine-tuning experiments to hone our prompt performance strategy • Created several new pages and redesigns for various monitoring flows, including our Leaderboard, Project Dashboard, Prompt Template Dashboard • Designed and implemented our LLM call cost tracking system, making requisite changes throughout our application, database, and SDKs • Created a simple web-based MCP Client and MCP Server • Built a POC to integrate CloudFlare logs into our eval generation workflow • Significant overhauls and redesigns of several data-heavy UI tables throughout the application • Improved our testing apparatus with several Checkly E2E tests (written with Playwright) for core UI flows • Collaborated with our designer, product manager, and CEO for new page and component designs • Various other API, database, and UI features Tech: Next, React, Node, Postgres, Temporal, Timescale, VisX, GraphQL, Hasura, OpenAI, Claude, Gemini, HuggingFace, Checkly, Playwright, ChakraUI, tRPC, TanStack Table & React Query ### Principal Software Engineer @ Rocket Insights (now DEPT®) Jan 2022 – Jan 2024 | New York, New York, United States • Developed and refined a variety of full-stack web applications (React / Typescript / Redux / Next / SCSS / Node / GraphQL / Postgres) for both startups and Fortune 500 companies, including a media-based event discovery platform, several video-centric live event websites, and a commercial real-estate analytics platform • Advised clients and team members on a variety of matters, including technical architecture decisions, UI/UX best practices, and technical details of pursuing Web3 opportunities and the crypto landscape • Wrote smart contracts, NFT minting protocol, and crypto payment integration for a decentralized music licensing startup based on the Algorand Network • Created data visualizations using Highcharts to demonstrate a variety of economic trends ### Senior Software Engineer @ Rocket Insights (now DEPT®) Jan 2020 – Jan 2023 | New York, New York, United States • Developed and refined a variety of full-stack web applications (React / Typescript / Redux / Next / SCSS / Node / GraphQL / Postgres) for both startups and Fortune 500 companies, including a media-based event discovery platform, several video-centric live event websites, and a commercial real-estate analytics platform • Advised clients and team members on a variety of matters, including technical architecture decisions, UI/UX best practices, and technical details of pursuing Web3 opportunities and the crypto landscape • Wrote smart contracts, NFT minting protocol, and crypto payment integration for a decentralized music licensing startup based on the Algorand Network • Created data visualizations using Highcharts to show a demonstrate a variety of economic trends ### Software Engineer @ Circle Jan 2019 – Jan 2020 | New York, New York • Worked on a variety of projects and tech stacks, including: re-envisioning our cryptocurrency exchange's onboarding and Know-Your-Customer processes, adding the ability to use wires and credit cards for fiat deposits/withdrawals, and integrating cryptocurrency capabilities into the company's crowdfunding platform • Created, developed, and ran multiple A/B tests via Google Experiments • Refactored and improved Mixpanel implementation and event coverage • Developed multiple JavaScript libraries and Vue/VueX components for UI features, as well as PHP and Django APIs Tech: Vue, PHP, JavaScript, JQuery, Django, Python, Git, Mixpanel, CSS, HTML, Google Experiments, Postgres, MySQL, InVision, Zeplin ### Front End Developer @ Gavelytics Jan 2016 – Jan 2019 • Implemented a custom React.js application and user portal that permits lawyers to view and interact with uniquely critical and insightful pieces of analytics via a variety of D3-drawn data visualizations • Built a responsively designed Shopify storefront that hosts the company’s publicly available content • Aided with in-person user testing and feedback sessions of the product • Collaborated heavily with the UI/UX designer, sales team, and the CEO to optimally design and iterate the product ### Founder and Full Stack Developer @ Censi Jan 2015 – Jan 2016 • Developed a poll-centric social platform with interactive graphs, flexible data types, and integrated regression functions from scratch, using JavaScript, D3.js, PHP, MySQL, HTML5 and CSS3 • Designed relational databases, and server-side PHP code to efficiently store, access, and protect the requisite data • Configured cloud-based servers, and installed SSL certificates for secure widespread commercial use • Collaborated with third-party vendors to create original design assets ### Consultant @ Hitachi Consulting Jan 2014 – Jan 2015 Notable projects include: Client: Large International Automotive Manufacturer Role: Business Analyst, February 2015-Present • Gathered business requirements, created process flows, and drafted corresponding use cases for a client’s new e-commerce module • Supported account team during client interactions, and aided in general project management duties • Assured proper functionality and design of implemented web applications via QA testing and JIRA ticket tracking Client: Internal Role: Operations Research, January 2015-February 2015 • Researched client companies’ backgrounds and operational infrastructure to recommend cross-selling opportunities • Leveraged available data sets to augment reports with original analysis and graphical representations Client: Internal Role: Configuration Business Analyst, December 2014 – December 2014 • Configured data structures and corresponding data fields to match business needs • Resolved and reconciled complications regarding multiple incident log and SharePoint issues • Compiled and formatted client deliverables ### Director of Special Events @ HOOLIGAN Theatre Company Jan 2011 – Jan 2014 *Oversaw the brainstorming, development, and execution of nearly fifteen yearly events for a 200+ member student organization *Grew a team up to nine associates, developing a collaborative work-structure *Oversaw an annual working budget of over $20,000, grown from roughly $4,000 *Created and executed new, popular programming that have since become tradition *Led successful social media and grass roots marketing campaigns for these events, and other relevant company events *Participated in senior company meetings, contributing to the overall direction and management of the company ### Producer @ HOOLIGAN Theatre Company Jan 2012 – Jan 2014 *Initiated the company's successful (and winning) involvement in UCLA's Spring Spring's Production category, making HTC the first non-Greek organization to be accepted in the 80+ year history of the event. *Oversaw the hiring and role structure of a nine person creative team, and cast of 35 *Brainstormed and coordinated all funding efforts, and subsequent expenses *Ensured continuity of production's vision and development ### Compensation and Analysis Intern @ Oakwood Worldwide Jan 2013 – Jan 2013 | Los Angeles *Updated company's geographic differential system to properly adjust compensation data to current cost-of-living conditions, and market rates *Provided analytic reports on relevant compensation data for promotions, transfers, and high-level new hires *Aided in revision of company's incentive plans to align with changing strategy and business landscape *Performed job pricings and market research for new positions both domestically and internationally, primarily within the U.S., U.K., and Singapore ### Library Student Assistant IV @ Young Research Library Jan 2012 – Jan 2012 * Catalogued and processed government and international documents * Identified, researched, and designed remedies for library cataloging issues * Extensive use of Excel, including data entry and spreadsheet customization ### Poll Aide @ Orange County Board of Elections Jan 2009 – Jan 2009 * Answered phone calls from local polling stations * Recorded and consolidated election results from certain local areas ## Education ### B.A in Business Economics; Specialization in Computing UCLA ### Advanced Regents Diploma Minisink Valley High School ## Contact & Social - LinkedIn: https://linkedin.com/in/jeffbrosenberg --- Source: https://flows.cv/jeffrosenberg JSON Resume: https://flows.cv/jeffrosenberg/resume.json Last updated: 2026-04-13