Full Stack Web Application Engineer – TypeScript / React / SQL

Full Stack Web Application Engineer – TypeScript / React / SQL

Posted Today by Siena Partnership

£88 Per hour
Undetermined
Undetermined
London Area, United Kingdom

Summary: The Full Stack Web Application Engineer role involves designing, building, and iterating bespoke web applications for a fintech scale-up. This hands-on position requires strong technical skills in TypeScript, React, and SQL, with a focus on solving complex business problems. The engineer will collaborate with senior stakeholders to enhance workflows and decision-making through modern software solutions. The role is contract-based and requires a UK-based candidate with the right to work in the UK.

Key Responsibilities:

  • Building bespoke web applications from scratch.
  • Partnering with senior stakeholders to understand problems and shape solutions.
  • Developing backend functionality using TypeScript.
  • Building frontend interfaces using React.
  • Working with SQL databases.
  • Creating tools that improve business workflows and decision-making.
  • Using AI-assisted development tools and workflows to accelerate delivery.
  • Iterating quickly based on user feedback.

Key Skills:

  • Strong TypeScript experience.
  • Proven experience building web applications.
  • Full stack engineering experience, ideally with a backend bias.
  • Strong SQL experience.
  • React experience.
  • Experience working in fast-moving technical environments.
  • Ability to communicate clearly with technical and non-technical stakeholders.
  • Highly desirable fintech or financial services experience.
  • Experience in a scale-up, SaaS, software, or product-led environment.
  • Experience with AI workflows or AI-assisted development.
  • Exposure to tools such as Claude Code, Cursor, Copilot, or similar.
  • Node.js.
  • Python.
  • Experience building internal tools, workflow platforms, dashboards, or data-heavy applications.

Salary (Rate): £87.50/hr

City: London Area

Country: United Kingdom

Working Arrangements: undetermined

IR35 Status: undetermined

Seniority Level: undetermined

Industry: IT

Detailed Description From Employer:

Full Stack Web Application Engineer – TypeScript / React / SQL Contract | UK-based | Up to £700/day We’re working with a growth equity-backed fintech scale-up that is building a suite of bespoke web applications for senior stakeholders across the business. They are looking for a Full Stack Web Application Engineer to join on a contract basis and help design, build, and iterate on high-impact internal tools from scratch. This is a hands-on engineering role for someone who enjoys solving complex business problems through clean, practical software. You’ll partner directly with senior stakeholders, understand what they need, and build web applications that improve how teams work with data, workflows, and decision-making. The environment suits someone highly technical, pragmatic, and comfortable moving quickly. You’ll be expected to own problems, build quickly, iterate with users, and use modern AI-assisted development workflows where useful.

What you’ll be doing

  • Building bespoke web applications from scratch.
  • Partnering with senior stakeholders to understand problems and shape solutions.
  • Developing backend functionality using TypeScript.
  • Building frontend interfaces using React.
  • Working with SQL databases.
  • Creating tools that improve business workflows and decision-making.
  • Using AI-assisted development tools and workflows to accelerate delivery.
  • Iterating quickly based on user feedback.

Must-have experience

  • Strong TypeScript experience.
  • Proven experience building web applications.
  • Full stack engineering experience, ideally with a backend bias.
  • Strong SQL experience.
  • React experience.
  • Experience working in fast-moving technical environments.
  • Ability to communicate clearly with technical and non-technical stakeholders.

Highly desirable

  • Fintech or financial services experience.
  • Experience in a scale-up, SaaS, software, or product-led environment.
  • Experience with AI workflows or AI-assisted development.
  • Exposure to tools such as Claude Code, Cursor, Copilot, or similar.
  • Node.js.
  • Python.
  • Experience building internal tools, workflow platforms, dashboards, or data-heavy applications.

This could suit someone who enjoys

  • Turning messy business problems into clean software.
  • Building from scratch rather than maintaining legacy systems.
  • Working closely with smart, senior users.
  • Using AI tools to speed up development.
  • Owning delivery end-to-end.
  • Working in a high-performance fintech environment.

Requirements

  • UK-based.
  • Available for contract work.
  • Right to work in the UK.
  • No sponsorship requirement.
  • Day rate up to £700/day.