Senior Fullstack Developer (For UK Client, Proficient English required)

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We are looking for a Senior Full-Stack Developer to join our engineering team. In this role, you will work across the full technology stack, building and maintaining backend services, APIs, web applications, and mobile solutions. You will collaborate closely with cross-functional teams and leverage AI-powered development tools to deliver scalable, high-quality software in a fast-paced and innovative environment.

Responsibilities

Design, build, and maintain features across backend services, web, and mobile surfaces.
Work within our agentic development workflow, leveraging custom AI agents to accelerate delivery and improve quality.
Collaborate closely with product, design, and other engineers; clear written and verbal communication is essential.
Contribute to architecture decisions and technical direction across the platform.
Write clean, well-tested code and participate in peer code reviews.
Adapt to our polyglot codebase, picking up any language or framework as needed.

Requirements

Core

5+ years of professional software development experience in a full-stack capacity.
Proven ability to work across backend, frontend web, and mobile within a single product.
Proficient in English, both written (documentation, async communication) and spoken (meetings, reviews).
Strong understanding of software architecture, API design, and testing practices.
Comfortable working in a fast-paced, iterative product environment.

Languages & Frameworks

We work across multiple languages. You do not need prior experience in all of them — what matters is genuine enthusiasm for polyglot development and a track record of picking up new languages quickly.

Go — backend services and APIs.
JavaScript / TypeScript with React — web frontend.
Java — backend and platform services.
Swift — iOS/macOS mobile development.
Dart (Flutter) — cross-platform mobile.

Agentic Development

Experience working with AI coding tools, agents, or agentic workflows in a professional setting.
Ability to learn and operate within a custom agentic development process (tooling and workflow training provided).
Understanding of how to effectively collaborate with AI agents to improve development velocity and code quality.

Nice to have

Experience building or maintaining collaborative or real-time platforms.
Familiarity with LLM APIs or prompt engineering.
Prior experience contributing to developer tooling, internal platforms, or workflow automation.
Track record of working across distributed or async-first teams.

Benefits

A genuinely modern development experience — our agentic workflow is a real competitive advantage and a compelling environment to work in.
A senior role with meaningful influence over technical direction.
A small, focused team where your contributions are visible and impactful.
Competitive compensation and flexible working arrangements.