Research engineer, model inference and serving
You’d build and run the systems that serve H’s models, including inference for computer-use agents.
- London, 3 days a week
- Full time
- Inference
- Pay not listed
This job is open.
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Jack’s take. Jack is an AI agent for the next step in your career. When there’s a mutual match, he introduces you to the hiring manager.
“You need production machine-learning infrastructure experience. You also need an advanced degree with research output, a top-venue paper, a research internship, or substantial open source.”
Who it suits
A good fit
- have run inference or serving for real models, ideally with vLLM, SGLang, or a similar engine
- write Python and a systems language such as Rust, C++, or Go
Think twice
- haven’t worked on production machine-learning infrastructure
- don’t have a research credential of the kind the job lists
- don’t want about 3 days a week in the London office, or travel to another H Company office every 4 to 6 weeks
What you’d do
- Build and operate the systems that serve H’s models, including multimodal inference for computer-use agents.
- Work across the inference engine and the serving layer, including routing.
- Improve the latency, throughput, and cost of serving the models.
What they ask for
- You have worked in a modern cloud environment and with production machine-learning infrastructure.
- You’ve shipped software in Python and a systems language.
- You have used PyTorch or JAX, and you know transformers and multimodal models. Industry experience is preferred.
- You have an advanced degree with research output, a publication at a top AI or systems venue, a research internship, or substantial open source.
How it works
- The job is in London, about 3 days a week in the office.
- You travel to another H Company office about every 4 to 6 weeks.
- The posting doesn’t list pay.
What to know about this job
Open at least 15 weeks. Half of London AI engineer jobs have closed by week 9.
- Week 9Half of London AI engineer jobs have closed
- Week 15This job has been open this long
In November 2026, H Company had 2 research engineer jobs open whose titles name London.
The platform builder, 25% of London AI engineer jobs
- 46%The product builder. Builds product features on large language models, from agents to search, and checks the answers hold up.
- 25%The platform builder (this job). You serve H’s models in production, including inference for computer-use agents.
- 23%The model builder. Trains and fine-tunes their own models, such as recommendations, vision or fraud, and ships them into the product.
Shares of open AI engineer jobs in London.
Most new London AI engineers weren’t AI engineers before
- 71% of people who became AI engineers in London weren’t AI engineers in their last job.
- 47% of them came from a startup or scale-up.
H Company doesn’t list pay for this job
The London AI engineer guide shows what AI engineers in London expect to earn.
What London AI engineers earnWorth asking the hiring team
- “Does a master’s count as the advanced degree?”
- “How is the time split between operating the stack and inference research?”
Jack’s take on H Company
- It aims to work with 5 to 10 enterprise customers in 2026, up from 2 or 3 in 2025
- It raised a $220M seed round in 2024 from investors including Accel, Amazon and Samsung
- The team has more than doubled to over 100 people since 2024
- A former Palantir director runs it, with leaders hired from Palantir, Multiverse Computing and Meta
- Some of its people work 9 to 12 hours a day
- Based in Paris, London, New York and San Francisco
- Founded 2023
- 30 open jobs
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About this page
Jack & Jill isn’t H Company’s recruiter. We summarized this job from H Company’s public careers page, where you can apply. We check whether it’s still open each time you open this page. The market numbers come from our London AI engineer guide and the company facts from H Company’s page. We last checked this summary against the posting on November 9, 2026. Jack’s take is Jack & Jill’s own.