As a Principal Machine Learning Engineer, you will co-define Speechmatics’ technical vision while remaining hands-on in the Modelling Team. You will bridge the gap between cutting-edge research and production systems, developing next-generation transformer models and optimizing inference for global scale. This is a high-ownership role focused on shipping real-world impact.
Principal Machine Learning Engineer at Speechmatics
Join the world leader in speech recognition AI as a Principal Machine Learning Engineer at Speechmatics. If you're an expert in transformer architectures and self-supervised learning who thrives at the intersection of research and production, this high-impact London-based role offers the autonomy to ship models that work where others fail.
About this role
Role overview
About the company
Speechmatics is a technology company specializing in artificial intelligence-driven speech recognition and voice AI infrastructure. It provides automatic speech recognition (ASR), speech-to-text (STT), text-to-speech (TTS), translation, summarization, sentiment analysis, and topic detection services, supporting over 50 languages and dialects with high accuracy across accents, noisy environments, and multi-speaker scenarios. The company serves enterprises, developers, and partners in industries such as media & broadcast, contact centers, healthcare, education, legal, finance, and AI infrastructure, enabling real-time and batch transcription for applications like captioning, compliance, and voice agents.[1][5]
What you'll do
What you will do
- Develop and deploy advanced ML models using Python and PyTorch, translating research into scalable, maintainable production services and services.
- Optimise large-scale model inference using strategies like dynamic batching, flash attention, and speculative decoding to improve speed and cost efficiency.
- Define and enforce best practices for model lifecycle management, data quality, and evaluations across the entire ML stack.
Who you are
Who this is a fit for
- Deep expertise in building and shipping production-grade ML systems, with a strong foundation in modern transformer architectures and self-supervised learning.
- Proven track record in distributed training and optimizing inference at scale, bridging the gap between research models and production-ready code.
- Expert proficiency in Python and ML frameworks such as PyTorch, complemented by experience in MLOps, CI/CD pipelines, and containerization.
Why this role
Why this role is remarkable
- Lead the technical direction of a $62M Series B scale-up that recently saw 4x growth in real-time usage and serves global customers.
- Work at the rare intersection of high-rigor ML research and large-scale production, shipping models that solve real-world problems like accents and noise.
- Take full ownership of technical domains, raising the bar for a talented team of 10+ engineers while developing groundbreaking bilingual and medical models.
Jack & Jill
How Jack & Jill work together
Meet Jack
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If it’s a match and the company wants to meet you, they’ll make the intro. In the meantime, if you’d like, Jack will send you excellent alternatives.