Junior C++ Engineer (Low-Level) - up to £110k base + Bonus in City of London

We are partnering with an exciting, disruptive technology company working at the intersection of machine learning, high-performance computing, and GPU acceleration. The team builds performance-critical software that helps power the next generation of AI and data-driven applications across industries such as autonomous systems, healthcare, and immersive gaming.

Their mission is to push the boundaries of performance in ML and AI workloads using modern software engineering practices and cutting-edge hardware. This is a great opportunity for a junior engineer with a strong foundation in modern C++ who’s excited to learn about performance optimization, GPUs, and ML systems in a supportive, high-impact environment.

We are looking for a Junior C++ Engineer (1–4 years’ experience) to join the ML performance and optimization team. You’ll work on high-performance C++ codebases, contributing to systems that run on GPU-accelerated platforms and support machine learning workloads.

This role is ideal for someone who enjoys writing clean, efficient modern C++, cares about performance, and wants to deepen their understanding of how software interacts with hardware. You’ll be mentored by experienced engineers and gradually exposed to GPU optimization, ML infrastructure, and performance-critical systems as you grow in the role.

• Develop and maintain modern C++ (C++17/20) code used in performance-sensitive systems
• Contribute to components that support GPU-accelerated and ML-related workloads, with guidance from senior engineers
• Profile, debug, and improve performance of existing code, with a focus on efficiency and scalability
• Collaborate with ML engineers and systems engineers to integrate and optimize new features
• Learn and apply performance best practices related to memory usage, concurrency, and parallelism
• Participate in code reviews and contribute to improving code quality and engineering standards

1–4 years of professional experience in C++, with a strong grasp of modern C++ concepts. Solid understanding of core software engineering fundamentals (data structures, algorithms, debugging). Interest in performance-aware programming, memory management, and efficient systems. Experience developing on Linux or similar environments. Curiosity about machine learning systems, GPU computing, or high-performance software — prior experience not required.

Familiarity with ML frameworks (e.g. Interest in high-performance computing, graphics, or low-level systems programming.

Comprehensive Health & Wellness Package, including mental health support. Learning & Development Budget for courses, mentorship, and conferences. Adventure Days — one paid day per quarter for something you love.