Principal / Senior UI Software Engineer - HTML5, React, Typescript, JS - Trading sought by leading financial services company based in the city of London. Proven experience as a senior/principal engineer in high-performance trading systems or similar domains. Demonstrable experience in HTML5, React 16/17, Typescript4/5, JavaScript UI Libraries such as Material UI or Ant Design. CSS pre-processors such as SASS and LESS Testing frameworks e.g. Jest Performance profiling and optimisation Build tools such as Webpack Code quality and governance tools such as Sonarqube. Responsive design and cross-browser compatibility Version control systems such as git i.e. gitlabs Agile development methodologies i.e. Scrum Please apply for further details.