Associate Software Developer (Web)

FlexTrade; City Of London; On-site; GBP 30,000 - 52,000; Full time

Job summary

FlexTrade Systems, Inc. is seeking an Associate Web Developer to join the FlexONE team in London. You'll contribute to development across web and mobile applications using a Scala + Play backend and a React + AG-Grid frontend, building features, fixing issues and improving usability.

The role offers collaboration with senior engineers, guidance, and opportunities to learn Scala/Play, TypeScript, and mobile cross‑platform development as the product evolves from MVPs to a full companion to desktop.

Qualifications

• Experience building web applications using React and TypeScript.
• Familiarity with Git for version control.
• Familiarity with Scala, Java, or other JVM languages and willingness to learn Scala/Play.
• Exposure to mobile development and interest in cross‑platform mobile apps.
• Understanding of APIs, web app structure and user‑centered design.
• Clear, curious communicator who works with engineers and non‑engineers.

Responsibilities

• Build features across the stack with guidance from seniors.
• Fix bugs reported by customers or QA teams.
• Write clean, tested code and respond to reviews to improve reliability.
• Support mobile evolution and assist with cross‑platform migration under guidance.
• Collaborate with developers, testers and product stakeholders to deliver practical solutions.

Skills

React and TypeScript

Git version control

Scala/Java/JVM languages

Mobile development awareness

Architecture & Design

Communication

Tools

Jenkins

GitLab

SonarQube

IntelliJ IDEA

Job description

FlexTrade Systems is a provider of customized multi-asset execution and order management trading solutions for buy- and sell-side financial institutions. Through deep client partnerships with some of the world's largest, most complex and demanding capital markets firms, we develop the flexible tools, technology and innovation that deliver our clients a competitive edge. Our globally distributed engineering teams focus on adaptable technology and open architecture to develop highly sophisticated trading solutions that can automate and scale with your business strategies.

At FlexTrade, we hold our values close to heart, with pride and gratitude, as they guide us in everything that we do. We are dedicated to giving our clients a competitive edge, taking ownership of our responsibilities, being flexible to adapt to ever changing environment and technology, bringing integrity to ever interaction and we continue to improve, grow together and collaborate as one team. All of these while having fun truly makes FlexTrade a wonderful place to work.

The Team

We are looking for an amazing developer to join our team building FlexTrade’s OEMS platform, FlexONE, which is our state-of-the-art, fully integrated Order Management System and Execution Management System. This system was built from the ground up starting in 2013 and is written entirely in Scala.

The FlexONE team is split between our Milwaukee office, where the product was first developed, and our London office, which is now predominantly responsible for development of the UI for the application.

The London team is an experienced group of Java and Scala developers, with a deep understanding of UI and UX design. We deliver our software using agile methodologies, and we encourage best practices such as TDD, code reviews and pair programming for knowledge sharing and learning. Our team owns all aspects of the features they work on, from designing solutions to meet customer or product requirements, through implementation, QA and delivery. Each team member works on every part of the system.

About You

As an Associate Web Developer, you’ll join our FlexONE team and contribute to development across our web and mobile applications. You’ll build your skills across a Scala + Play Framework backend and a React + AG-Grid front-end, while using gRPC to communicate with our core product’s backend systems. Working with guidance from senior engineers, you’ll help build features, fix issues, improve usability, and support the ongoing evolution of our Web and Mobile apps from MVPs toward comprehensive companions to the desktop application.

Responsibilities

• Build Features: Implement well-scoped, maintainable features across the stack with support from senior engineers.

• Fix Bugs: Help to triage and resolve bugs found by either our customers or our internal QA teams.

• Code Quality: Write clean, tested code and respond to review feedback to improve reliability, performance, and maintainability.

• Support Mobile Evolution: Assist with maintenance and incremental development of the current mobile app and support future migration work under technical guidance.

• Collaboration: Work closely with developers, testers, and product stakeholders to understand requirements, clarify details, and deliver practical solutions.

Tech Stack

• Backend: Scala, Play Framework, REST/JSON and gRPC

• Frontend: React, TypeScript, AG-Grid

• Mobile: Current app in CodenameOne, target migration to React Native (or similar JS-based cross-platform framework)

• Tooling: Jenkins, GitLab, SonarQube, IntelliJ IDEA

• Foundational full stack expertise

  • Experience building web applications using React and TypeScript

  • Familiarity with typical software development workflows, including using Git for version control

  • Familiarity with Scala, Java, or another JVM language, with willingness to learn Scala and Play Framework.

• Mobile Interest: Exposure to mobile development and interest in learning cross-platform mobile development with React Native

• Architecture & Design: Basic understanding of APIs, web application structure, and user-focused design principles.

• Communication: Clear, curious communicator who collaborates well with both engineers and non-engineers.

FlexTrade Systems, Inc. is an equal opportunity employer and makes employment decisions without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, protected veteran status, disability status, or any other status protected by law.

FlexTrade UK Ltd. conducts a pre-employment screening which consists of a Criminal History, Background and Credit Check for successful candidates.