{"id":594335,"url":"https://alion.io/job/janestreet-dev-machine-learning-research-engineer","title":"Machine Learning Research Engineer","company":{"id":7349,"name":"Jane Street","domain":"janestreet.com","url":"https://alion.io/company/jane-street","size_band":"1001-5000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Greenhouse","truth_index":{"grade":"B","score":75,"open_postings":170,"ghost_share":0.335,"stale_share":0,"repost_share":0,"time_to_fill_p50_days":141,"computed_at":"2026-10-16T05:45:00Z"}},"role":"AI/ML","role_family":"AI/ML","seniority":null,"employment_type":null,"work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["London, United Kingdom"],"countries":["GB"],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":null,"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Machine Learning","optional":false},{"name":"PyTorch","optional":false},{"name":"TensorFlow","optional":false}],"status":"live","first_seen_at":"2024-05-20T21:18:21Z","employer_posted_date":"2026-09-28","last_verified_at":"2026-10-16T20:46:30Z","board_verified":true,"closed_at":null,"days_open":879,"trust":{"level":"ghost","repost_count":0,"flags":["stale","company_stale"],"days_open":878},"description":"We are looking for a Research Engineer with robust experience in machine learning and strong mathematical foundations to join our growing ML team and to help drive the direction of our ML platform.\nMachine learning is a critical pillar of Jane Street's global business. Our ever-evolving trading environment serves as a unique, rapid-feedback platform for ML experimentation, allowing us to incorporate new ideas with relatively little friction. Our ML team is full of people with a shared love for the craft of software engineering, and for designing APIs and systems that are delightful to use. \nWe’ll rely on your in-depth knowledge of the ML ecosystem and understanding of varying approaches - whether it’s neural networks, random forests, gradient-boosted trees or sophisticated ensemble methods - to aid decision-making so we apply the right tool for the problem at hand. Your work will also focus on enhancing research workflows to tighten our feedback cycles. Successful ML Research Engineers will be able to understand the mechanics behind various modelling techniques, while also being able to break down the mathematics behind them. We’re looking for people who can be a true bridge between research and engineering, and can help us push forward the frontier of our model capabilities at all points of the stack. This could involve enabling a new scale in our technology stack, sitting on a team of Researchers to rapidly prototype a new research idea, or building workflow APIs that support a wide range of use cases.\nIf you’ve never thought about a career in finance, you’re in good company. Many of us were in the same position before working here. While there isn’t a fixed list of qualifications we’re looking for, if you have a curious mind and a passion for solving interesting problems, we have a feeling you’ll fit right in. \nWe're looking for someone with:\nExperience building and maintaining training and inference infrastructure, with an understanding of what it takes to move from concept to production\nA strong mathematical background; Good candidates will be excited about things like optimisation theory, regularisation techniques, linear algebra and the like\nA passion for keeping up with the state of the art, whether that means diving into academic papers, experimenting with the latest hardware or reading the source of a new machine learning package\nA proven ability to create and maintain an organised research codebase that produces robust, reproducible results while maintaining ease of use\nExpertise wrangling an ML framework - we're fans of PyTorch, but we'd also love to learn what you know about Jax, TensorFlow or others\nAn inventive approach and the willingness to ask hard questions about whether we're taking the right approaches and using the right tools\nFluency in English required\nIf you're a recruiting agency and want to partner with us, please reach out to .","description_format":"text","description_chars":2941,"description_truncated":false,"requirements":{"experience_years_min":null,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":null,"security_clearance":false,"languages":[{"language":"English","level":"Advanced (C1)","optional":false}]},"benefits":[],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["Hedge Funds & Alternative Investments"],"lifecycle":[{"event":"open","at":"2026-09-10T14:59:02Z"}],"visa":[{"country":"GB","licensed_sponsor":true,"evidence":"Licensed UK visa sponsor (Senior or Specialist Worker, Skilled Worker)","filings_12m":null,"filings_prev_12m":null,"green_card_filings_12m":null,"median_offered_wage_usd":null,"route":"Global Business Mobility: Senior or Specialist Worker; Skilled Worker","cap_exempt":false,"checked_at":"2026-10-16T06:21:30+00:00","sources":["UK Home Office: register of licensed sponsors (workers)"],"filings_for_role_12m":0}],"liveness":{"score":4,"band":"cold","label":"Long shot","p_open":1,"p_active":0.151,"p_room":0.28,"age_days":878,"expected_fill_days":141,"reasons":["conf:2","velocity","ghost","win:tail","crowd:brand"],"computed_at":"2026-10-16T05:45:00Z"},"pay":null,"html_url":"https://alion.io/job/janestreet-dev-machine-learning-research-engineer","json_url":"https://alion.io/job/janestreet-dev-machine-learning-research-engineer.json","meta":{"generated_at":"2026-10-16T22:04:03Z","cache_seconds":300,"methodology":"https://alion.io/methodology","terms":"https://alion.io/terms","contact":"https://alion.io/contact","api":"https://alion.io/developers","about":"Alion is a live layer of people, companies and AI agents: who they are, whether they are real and active right now, what they do and how to work with them, readable by people and by agents and paid per call.","catalog":"https://alion.io/catalog.json","usage":{"tier":"crawler_verified","counted_by":"address","units_charged":1,"used_today":3423,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-17T00:00:00Z"}},"offers":[{"id":"company.slices","title":"One company in depth, by slice","status":"live","price":{"credits":0.02,"usd":0.002,"plus_per_slice":{"credits":0.05,"usd":0.005}},"unit":"per company, plus each slice with data","note":"the employer in depth","call":{"mcp_tool":"get_company","arguments":{"id":7349},"rest":"https://alion.io/mcp/rest/get_company?id=7349"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fjanestreet-dev-machine-learning-research-engineer"},{"id":"market.stats","title":"A market slice: pay, demand and time to fill","status":"live","price":{"credits":1,"usd":0.1},"unit":"per slice","note":"pay, demand and time to fill for this role and place","call":{"mcp_tool":"market_stats"},"human":"https://alion.io/catalog?offer=market.stats&for=job%2Fjanestreet-dev-machine-learning-research-engineer"},{"id":"job.search","title":"Open jobs by role, technology, place, pay and visa","status":"live","price":{"credits":0.02,"usd":0.002},"unit":"per posting in a list","note":"similar open postings","call":{"mcp_tool":"search_jobs"},"human":"https://alion.io/catalog?offer=job.search&for=job%2Fjanestreet-dev-machine-learning-research-engineer"},{"id":"company.verify","title":"Is this company real and active right now","status":"pilot","price":null,"unit":"per company","request":{"url":"https://alion.io/catalog/request","method":"POST","body":"{\"offer\": \"company.verify\", \"for\": \"job/janestreet-dev-machine-learning-research-engineer\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fjanestreet-dev-machine-learning-research-engineer"}]}