Technical Game Designer in Cardiff

Please note that this is a hybrid position based in Cardiff, requiring 3 days onsite each week, with the option for remote work on the remaining days.

Part of the Rocket Science Group, Atomic Theory is a multinational team of seasoned AAA veterans with roots extending from Blizzard, PUBG, Epic, and Unity. We have a track record of delivering player-centric, AAA-quality experiences, and we're unwavering in our commitment to performance, accessibility, and the engineering frameworks that underpin exceptional gameplay.

Atomic Theory is more than just a studio — it's a collaborative space where diverse experiences intersect to solve the toughest challenges in modern game development. With offices in Albany NY, Cardiff UK, and Brighton UK, we thrive at the opportunity to Get Sh!t Done on a global scale.

ABOUT THE ROLE: Engaging players through thoughtful, well-crafted game systems is at the heart of our design philosophy. As a Technical Game Designer, you'll sit at the intersection of design and engineering, owning the implementation and technical execution of gameplay systems in Unreal Engine 5. You'll be equally comfortable shaping a design vision on paper and bringing it to life through Blueprints, data-driven tooling, and close collaboration with engineering teams.

This role is ideal for experienced designers who thrive on iteration and love getting deep into the engine, whether prototyping combat systems, tuning game economies, or building robust live-service features. You will work in collaborative co-development environments, partnering with our clients and internal teams to deliver high-quality gameplay across a range of AAA projects.

WHAT YOU'LL DO:

• Design and implement game mechanics, systems, and features in Unreal Engine 5
• Build, maintain, and iterate on gameplay systems using Blueprints and UE5 tooling, partnering closely with engineers for C++ handoffs
• Develop clear and detailed design documentation, including GDDs, system specs, and data sheets
• Prototype and validate gameplay elements directly in-engine, iterating rapidly based on internal testing and player feedback
• Balance game systems, progression mechanics, and economies to ensure engaging experiences across diverse playstyles
• Collaborate cross-functionally with designers, engineers, and artists to ensure features are both engaging and technically feasible
• Analyse player behaviour data to refine game balance and engagement strategies
• Advocate for accessibility and usability, ensuring designs are intuitive and inclusive
• Contribute to co-development workflows, working seamlessly with partner studios across time zones

WHAT WE VALUE:

• Experience designing and implementing gameplay systems for AAA or high-quality independent game titles
• Deep understanding of game design fundamentals, including player psychology, game loops, and progression mechanics
• Proven Unreal Engine 5 proficiency — comfortable implementing and testing mechanics directly in-engine via Blueprints and UE5 systems
• Strong analytical and problem-solving skills, with a commitment to data-driven design decisions
• Ability to document and present design ideas effectively, fostering collaboration across disciplines
• Experience in fast-paced, iterative development environments with an understanding of agile methodologies
• Passion for gaming and a strong understanding of player motivations across different genres

YOU MAY ALSO HAVE:

• Experience designing multiplayer, live-service, or systemic games
• Background in game economy design, balance, or monetisation strategies
• Experience scripting in Blueprint, Lua, or other game development languages
• Familiarity with UE5 features: Mass Entity, Gameplay Ability System (GAS), PCG, or similar
• Experience with AI behaviour, mission design, or player progression systems
• Prior co-development experience, collaborating with external studios or publishers

WHAT WE CAN OFFER:

• Hybrid Working Arrangement: As a member of our team, you’ll have the flexibility to work at home and collaborate with your fellow engineers in person!
• Competitive Salary and Benefits Package: Your health and wellbeing is important to us, so we offer a variety of benefits including: Medical, Dental, and Vision Insurance
• 401(k) Retirement Plan with Employer Matching
• Annual Leave, Plus 9 Paid Holidays and Winter Break Office Closure
• Annual Research Credit: We always encourage personal growth, so we provide all of our team members with an annual credit to further enhance your skills!
• Professional Development: We offer biannual reviews, as well as opportunities to collaborate across disciplines, internal tech talks, and the chance to learn from specialists with backgrounds from across the games and software development industries.
• Work-Life Balance: We really believe that home life comes first and we promote a flexible working environment. And as an added bonus: We don’t crunch!
• Family Friendly: We understand the importance of family, which is why we offer 6 weeks full of Maternity, Paternity, and Adoption Leave to support you during this exciting time!
• Office Perks: In addition to everything above, we also provide: Weekly Team Lunches (plus Snacks!) Fully Equipped Team Lounge, Including our Favourite Consoles and Games And, most importantly, a supportive and creative working environment made up of talented and friendly people, as well as the opportunity to work on some pretty cool games and projects – if we do say so ourselves!

A FRIENDLY NOTE FROM THE RECRUITMENT TEAM: Let us do the work for you: Even if your profile isn’t an exact match for all of the qualifications listed above, we still want you to apply. Our team members come from a variety of different industries, not all of which are immediately relevant to game or software development, and we welcome all candidates of similarly varied backgrounds, communities, and identities.

Rocket Science is an equal opportunity employer and is committed to providing a worry-free workplace void of discrimination or harassment. Rocket Scientists are expected to foster and champion an environment in which everyone has the opportunity to feel included and is afforded the respect and dignity they deserve.

Rocket Science does not accept unsolicited résumés from recruiters, employment agencies, or staffing firms.