ML Research Engineer — Agentic AI Systems & Equity

Callosum Technologies Ltd.; Greater London; Hybrid; GBP 120,000 - 180,000; Full time

Benefits offered by this job

Competitive salary

Equity & Ownership

Private healthcare

Visa sponsorship and relocation

Job summary

Callosum Technologies Ltd. in London is hiring a research-focused engineer to develop agentic AI systems across heterogeneous models and hardware, turning theory into scalable infrastructure. You will design experiments, analyze memory and task decomposition, and build observability tools that the whole company uses.

Strong communication and rigorous discipline are essential. Join a team building the layer beneath this evolving technology, with latitude to choose problems and influence the

Qualifications

• Evidence you can run research questions end-to-end and publish results that others can build on.
• Hands-on experience with LLMs in agentic settings, multi-step tasks, tool use, and long horizons.
• Real experimental discipline with clear hypotheses, controlled comparisons, and ablations.

Responsibilities

• Design and run experiments that isolate why agentic systems fail and translate findings into interventions.
• Advance core research themes: context/m memory management, agent steering and decomposition.
• Build agent analysis and evaluation infrastructure—observability, behaviour analysis, and evaluation harnesses.

Skills

LLMs in agentic

Experimental discipline

Strong engineering

Communication skills

Research design

Tools

SGLang

vLLM

Job description

Callosum Technologies Ltd. in London is hiring a research-focused engineer to develop agentic AI systems across heterogeneous models and hardware, turning theory into scalable infrastructure. You will design experiments, analyze memory and task decomposition, and build observability tools that the whole company uses.

Strong communication and rigorous discipline are essential. Join a team building the layer beneath this evolving technology, with latitude to choose problems and influence the