Senior UI Developer (React/TypeScript)

JavaScript

-, Warszawa

Caspian One

2 300PLN

Net per day - B2B

Full-time

B2B

Senior

Hybrid

Tech stack

HTML

master

Redux

master

RxJS

master

React

master

CSS

master

TypeScript

regular

Azure DevOps

regular

Job description

Contract Type: B2B Contract

Duration: 6 month rolling contract with at least 2 years of work secured

Rate: Up to 2,300 PLN per day (depending on experience and seniority)

Location: Remote in Poland (only 1 day per month in-office initially)

About the Opportunity

Join a new team being established in Poland as part of an international expansion by a leading global financial institution. This is a rare opportunity to work on an in-house built pricing, execution, and trade processing platform for financial markets as part of a global development team.

Key Responsibilities

• Work across all delivery stages from requirements gathering to post-release support

• Own and collaborate on technical design decisions

• Break down large projects into manageable tasks and coordinate solution delivery

• Build new functionality within existing coding patterns and architecture

• Coach other developers and participate in hiring processes

• Develop complex, real-time event-driven multi-modular single page applications

Essential Requirements

• 7+ years of relevant development experience

• Expert-level skills in React, Redux, RxJS, NPM/Yarn, webpack, CSS, HTML

• Experience with CI/CD pipelines (e.g., Azure DevOps)

• Proven experience building complex, real-time (event-driven) multi-modular single page applications

• Strong software design principles and knowledge of design patterns

• Ability to optimize performance of latency-sensitive systems

• Full-stack development capability (preferably with Java backend experience)

• Fluent English communication skills

Preferred Qualifications

• Financial markets domain knowledge

• Experience with TypeScript in enterprise environments

• Background in high-performance trading systems

• Previous experience in international banking or financial services

What We Offer

• Competitive daily rate up to 2,300 PLN

• Long-term contract security with 2+ years of work already confirmed

• Remote-first working arrangement with minimal office requirements

• Opportunity to work on cutting-edge financial technology

• International collaboration with global teams

• Professional development through coaching and mentoring opportunities

Ideal Candidate Profile

You are a seasoned UI developer with deep expertise in React and modern JavaScript frameworks. You thrive in fast-paced environments where performance and reliability are critical. You have experience with real-time systems and understand the unique challenges of building user interfaces for financial applications.

Published: 09.08.2025

Meet the company

Caspian One

Caspian One is a financial technology services partner, delivering high-impact opportunities within global banks, hedge funds, and fintechs. We specialise in strategic skillset acquisition across Java, C#, QA/Testing, DevOps, Data Engineering, Front End (UI/UX), and Project Delivery (BA, PM, Scrum Master). From modernisation programmes to greenfield builds, we align expert resources with mission-critical priorities - enabling you to grow your expertise within fast-paced, business-driven environments.

Company profile

Office location