# Member of Technical Staff- Research Engineer (Harness Engineering and Agentic Orchestration) at Tessl Tessl is hiring a Member of Technical Staff- Research Engineer (Harness Engineering and Agentic Orchestration) for a remote role open to applicants in United Kingdom. Level rates it Builds AI ●●●●; you can [apply on Tessl](https://jobsbylevel.com/go/5e1e60e2-f77a-4b4d-bad5-37ff1094ee9b?utm_medium=ai-agent). AI Level 4, AI centrality 88 out of 100. Remote (London Office). ## Details - Company: [Tessl](https://jobsbylevel.com/companies/tessl) - AI level: AI Level 4 (score 88 out of 100) - Location: Remote (London Office) - Posted: May 28, 2026 - Apply: https://jobsbylevel.com/go/5e1e60e2-f77a-4b4d-bad5-37ff1094ee9b?utm_medium=ai-agent - Free CV review for this job: https://jobsbylevel.com/cv-review?job=member-of-technical-staff-research-engineer-harness-engineering-and-agentic-orchestration-at-tessl-c9ef13 ## Prepare for this job The job page lists 4 likely interview questions for this offer, with a CV checklist: https://jobsbylevel.com/jobs/member-of-technical-staff-research-engineer-harness-engineering-and-agentic-orchestration-at-tessl-c9ef13 ## Description About Tessl AI is transforming how software is built, and at Tessl, we're building the infrastructure for what comes next. We're developing a platform that enables engineering teams to build and run AI-powered software factories, where coding agents take on real development work, from picking up engineering tickets to implementing changes and creating pull requests. By combining structured context, reusable agent skills, automated workflows and evaluations, we're making AI-powered development more reliable, repeatable and scalable, while keeping humans in control. We're tackling some of the biggest challenges in autonomous software development, from code quality and security to helping organisations confidently adopt AI agents at scale. Founded by Guy Podjarny, previously founder of Snyk, Tessl is a fast-growing Series A startup backed by over $100 million in funding from investors including Index Ventures, Accel, GV and Boldstart. Joining Tessl means helping define an entirely new category of technology, solving ambitious technical challenges and shaping the future of software development. Overview of the role We're hiring a Research Engineer to join our AI Research (AIR) team. You'll work on the components that make the outer loop real: how agent harnesses orchestrate model behaviour, how we evaluate what's actually working, how pipelines turn production traces into the next round of improvement, and how we diagnose the failure modes that matter to real users. These aren't four separate workstreams — they're parts of one system, and we want people who see them that way. We expect you to sit close to customers — joining calls, watching sessions, reading traces — and to let real workflows shape your research priorities. You'll have meaningful autonomy and the resources to run substantial experiments where the bar for success is shipped impact. You'll report to our AI Research Lead, and collaborate closely with engineering, product, and design. What we're looking for We're explicitly building coverage across four skill areas. You don't need to be strong in all of them — but you should bring depth in at least one: Agent harness and orchestration design — how tools, context, and control flow combine to make a useful agent. Agentic eval methodology — task and repo-level evals, dataset curation, the craft of measuring what actually matters. Outer-loop and pipeline thinking — feedback loops, training-data flywheels, bandit-style optimisation, anything that goes beyond a single agent session. Failure-mode analysis — instrumenting agents, reading traces at volume, surfacing patterns engineering can act on. Essential 4+ years shipping AI/ML products in a startup or applied industry setting, with recent hands-on experience with LLMs and agentic systems. Demonstrated depth in at least one of the four skill areas above. Strong product and customer instincts: comfort joining customer calls, watching session recordings, and letting real workflows shape what you work on. Sharp evaluation judgement: benchmarks where they exist, vibes and quick prototypes where they don't, and the taste to know which is appropriate. Experience building datasets for evaluation or training, including the pipeline work that goes with it. Deeply curious about agents and excited about reshaping how software is built. Nice to have A Masters or PhD in a relevant computational field. Direct experience with coding agents or code-generation systems. Background in RL, bandits, or other outer-loop optimisation frameworks applied to LLMs. Experience building synthetic data, dataset infrastructure, or internal tooling that other engineers actually used. A project you can show us (GitHub links welcome) and a thoughtful answer to "Why Tessl?" What you'll do No two weeks will look the same. A flavour: Sit in on a customer session, understand how their agents are failing, design an eval that captures it, and drive a fix through to shipped improvement. Close a piece of the The description is cut here. Read the full offer: https://jobsbylevel.com/jobs/member-of-technical-staff-research-engineer-harness-engineering-and-agentic-orchestration-at-tessl-c9ef13 Source: https://jobsbylevel.com/jobs/member-of-technical-staff-research-engineer-harness-engineering-and-agentic-orchestration-at-tessl-c9ef13 ## Cite this page Level. https://jobsbylevel.com/jobs/member-of-technical-staff-research-engineer-harness-engineering-and-agentic-orchestration-at-tessl-c9ef13. Get job alerts: https://jobsbylevel.com/newsletter