IG Group Frontend Engineer interview questions & guide 2026

The following questions are representative of the patterns reported by candidates. Use these to identify gaps in your knowledge, rather than as a static list for memorization.

JavaScript Core Concepts

These questions assess your foundational understanding of the language, which is critical for building scalable applications at IG Group.

• What is a closure in JavaScript and how does it work?
• Can you explain the behavior of the this keyword in different contexts?

Preparation at IG Group requires a balance of theoretical knowledge and practical application. You should prepare to speak about your past projects with the same level of detail you would use to defend a technical architecture.

Technical Fluency – You must be comfortable explaining the "how" and "why" behind your code. Interviewers look for candidates who can articulate the trade-offs of their technical decisions rather than just providing a textbook definition.

Problem-Solving Agility – You will be evaluated on your ability to think through complex problems aloud. Even when faced with a coding test, your communication process is often as important as the final output.

Team Alignment – Expect to discuss your "ways of working." IG Group values engineers who can collaborate effectively, handle constructive feedback during pair programming, and contribute to a professional team culture.

The interview process at IG Group typically begins with a screening phase, often involving a recruitment consultant to assess your background and basic technical alignment. Following this, you can expect technical assessments that range from phone-based discussions to more formal coding challenges. The process is designed to test both your depth in core technologies like JavaScript and React, and your ability to maintain composure under pressure.

This timeline illustrates the progression from initial screening to technical deep dives. Candidates should use this as a roadmap to manage their energy; the earlier stages are conversational, while later stages often involve hands-on technical validation. Be prepared for variation in how feedback is delivered, and always remain focused on the technical objectives of each stage.

Technical Depth

You will be evaluated on your ability to apply core language features to real-world problems. Strong performance involves demonstrating a deep understanding of asynchronous programming, memory management, and browser rendering pipelines.

Be ready to go over:

• Asynchronous JavaScript – Handling promises, async/await, and event loops.
• Performance Optimization – Techniques like virtual scrolling, memoization, and efficient DOM manipulation.

As a Frontend Engineer, you are responsible for the end-to-end lifecycle of the features you build. You will collaborate closely with backend engineers, designers, and product managers to ensure that the user interface is not only visually consistent but also highly performant.

Your daily work will involve translating business requirements into technical specifications, writing clean and testable code, and participating in code reviews. You are expected to be an active participant in technical discussions, often helping to define the architecture for new modules or refactoring legacy components to improve stability and speed.

A competitive candidate for this role possesses a strong foundation in web standards and a pragmatic mindset toward engineering.

• Must-have skills: Deep expertise in JavaScript (ES6+), hands-on experience with React or similar frameworks, and a solid grasp of CSS/HTML5.
• Nice-to-have skills: Prior experience with financial trading platforms or high-frequency data applications, familiarity with Jasmine or other testing frameworks, and experience with performance profiling tools.
• Soft skills: Clear communication, the ability to explain technical trade-offs to non-technical stakeholders, and a collaborative approach to pair programming.

Q: How should I prepare for the coding test? A: Focus on clean, efficient code and, most importantly, talk through your thought process. Even if you are asked to solve a "contrived" problem, explaining your reasoning helps the interviewer understand your engineering mindset.

Q: Is there a specific focus on testing? A: Yes, understanding how to write effective tests—such as using Jasmine—is highly valued. Be prepared to discuss your testing philosophy and how you ensure code reliability.

Q: What is the culture like during the interview? A: The culture is professional and technical. You may encounter different styles of interviewers, so stay focused on the technical merit of your answers and remain calm if the environment feels demanding.

• Master the fundamentals: Do not rely solely on frameworks. Ensure you can explain core JavaScript concepts without relying on abstractions.
• Be ready for pair programming: Practice explaining your code as you write it. This is a standard way to assess how you would function within an IG Group team.
• Clarify the requirements: If a coding prompt seems ambiguous, ask clarifying questions before jumping into the implementation. This shows you are a thoughtful engineer.

The Frontend Engineer role at IG Group is a challenging opportunity to work on high-stakes, high-impact products. Success in this process relies on your ability to demonstrate deep technical expertise, clear communication, and a disciplined approach to problem-solving. By focusing on core JavaScript principles and your ability to articulate the "why" behind your code, you will position yourself as a strong candidate.

You can explore additional interview insights, practice questions, and preparation resources on Dataford. Stay focused on the fundamentals, remain communicative throughout your technical assessments, and approach every stage with a clear, strategic mindset.

This module provides insight into the compensation landscape for Frontend Engineers. Use this data to calibrate your expectations regarding total rewards, including base salary and potential performance-based components, ensuring you are prepared for salary discussions throughout the interview process.