Senior UI Developer (React/Typescript)B2B | 6-month rolling contract (minimum of 2 years secured work)Rate: Up to 2100 PLN/dayLocation: Warsaw (1 day per month onsite) About the OpportunityA leading global financial institution is expanding its engineering presence in Poland and is building a brand‑new team to support its international technology organisation. This is a unique chance to contribute to the development of an in‑house pricing, execution, and trade‑processing platform used across global financial markets.You will join a highly skilled engineering group working on complex, real‑time systems where performance, reliability, and clean architecture are essential.Key ResponsibilitiesContribute across the full SDLC, from requirements analysis to post‑release supportLead and influence technical design decisionsBreak down large initiatives into actionable tasks and coordinate deliveryDevelop new features within established architectural patternsMentor other developers and support hiring activitiesBuild and enhance real‑time, event‑driven, multi‑module single‑page applicationsEssential Requirements7+ years of professional software development experienceExpert knowledge of React, Redux, RxJS, NPM/Yarn, webpack, CSS, and HTMLHands‑on experience with CI/CD pipelines (e.g., Azure DevOps)Proven background in building complex, real‑time, event‑driven SPAsStrong understanding of software design principles and design patternsAbility to optimise performance in latency‑sensitive environmentsFull‑stack capability is a plus (ideally Java on the backend)Excellent communication skills in EnglishExperience in financial markets or trading systemsPreferred QualificationsStrong TypeScript experience in enterprise environmentsBackground working on high‑performance, low‑latency applicationsPrevious experience in international banking or financial servicesWhat We OfferCompetitive daily rate up to 2,100 PLNLong‑term contract stability with 2+ years of confirmed workRemote‑first setup with minimal onsite requirementsOpportunity to work on advanced financial technology platformsCollaboration with global engineering teamsProfessional growth through mentoring and knowledge‑sharing