{"id":174885,"url":"https://alion.io/job/letta-research-engineer-scientist-post-training","title":"Research Engineer / Scientist, Post-Training","company":{"id":48112,"name":"Letta","domain":"letta.com","url":"https://alion.io/company/letta","size_band":"1-10","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":{"grade":"B","score":75,"open_postings":4,"ghost_share":0,"stale_share":1,"repost_share":0,"time_to_fill_p50_days":null,"computed_at":"2026-10-16T05:45:00Z"}},"role":"AI/ML","role_family":"AI/ML","seniority":null,"employment_type":"full_time","work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["San Francisco, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":{"min_usd":165000,"max_usd":361000,"period":"year","method":"role_country_seniority_unknown","sample_n":4027},"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"AI Agents","optional":false},{"name":"Fine-tuning","optional":false},{"name":"Letta","optional":false},{"name":"OpenAI","optional":false},{"name":"Post-training","optional":false},{"name":"Python","optional":false},{"name":"PyTorch","optional":false},{"name":"Ray","optional":false},{"name":"Reinforcement Learning","optional":false},{"name":"Reward Modeling","optional":false},{"name":"SFT","optional":false},{"name":"Spark","optional":false},{"name":"Synthetic Data","optional":false},{"name":"Tool Use","optional":false}],"status":"live","first_seen_at":"2025-02-04T03:27:39Z","employer_posted_date":"2025-02-04","last_verified_at":"2026-10-16T19:44:20Z","board_verified":true,"closed_at":null,"days_open":619,"trust":{"level":"stale","repost_count":0,"flags":["stale"],"days_open":619},"description":"Solving Self-Improving Superintelligence\nThe human brain is a sponge. Today’s AI brains are brittle and rigid. At Letta, we’re building self-improving artificial intelligence: creating agents that continually learn from experience and adapt over time.\nFounded by the creators of MemGPT from UC Berkeley’s Sky Computing Lab (the birthplace of Spark and Ray). Backed by Jeff Dean, Clem Delangue, and pioneers across AI infrastructure. Our agents already power production systems at companies like 11x and Bilt Rewards, learning and improving every day.\nWe’re assembling a world-class team of researchers and engineers to solve AI’s hardest problem: making machines that can reason, remember, and learn the way humans do.\nNote that this role is in-person (no hybrid), 5 days a week in downtown San Francisco.\nYour role\nYou will pioneer post-training techniques that improve how well LLMs can be integrated into complete agentic systems. At Letta, you'll work with a world-class, tight-knit team of AI researchers and engineers towards our vision of self-improving superintelligence. Advance the field through open publishing of research through papers, technical reports, blog posts, and open-source code.\nWhat You’re Responsible For:\nTraining models for better agentic tool-use, particularly for context management\n\nDesigning mechanisms for continuous model weight updates post-deployment without catastrophic forgetting\n\nDesigning and run experiments to improve understanding of the interplay between data mixtures, training algorithms, and models\n\nBuilding infrastructure for generating and collecting synthetic data at scale\n\nBuilding challenging evals for measuring agentic capabilities\n\nWhat We're Looking For:\nProficiency in python and deep learning frameworks eg. PyTorch\n\nExpertise in post-training techniques e.g. SFT fine-tuning, reinforcement learning, reward models, preference learning\n\nAbility to balance execution speed with empirical rigor\n\nProven track record of impactful research (breakthrough publications and/or open-source contributions)\n\nReal-world impact beyond pure academic work\n\nOur culture\nSigns it could be a great fit:\nYou want to maximize your impact: you want work on a small, incredibly talented team where every individual plays a huge role in the team's success. You wonder what it would have been like to be at OpenAI when it was just a dozen people, or Google when it was just a couple of grad students in a garage.\n\nYou’re excited to go head-to-head with tech giants, frontier labs, and other startups that are many times our size in both headcount and funding.\n\nYou are fundamentally opposed to closed frontier AI that is controlled by a handful of billionaires and private tech companies.\n\nSigns it’s a bad fit:\nYou like stability, and get stressed out when there’s nobody telling you exactly what to do. We look for people that thrive in ambiguity and can intuit the most important problems by talking to customers and dogfooding our product.\n\nYou want to work a 9-5, and value clear separation of work from life. The stakes are the highest they've ever been, and the only moat is execution velocity. Operating on a strict 9-5 guarantees failure.\n\nYou value titles or want to people-manage. Letta is a flat company where every researcher and engineer is an individual contributor.\n\nOur Interview Process:\nInitial screen (30 min)\n\nTechnical screen (1-1.5 hours)\n\nPaid in-person work trial (2 days onsite in SF)","description_format":"text","description_chars":3448,"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":[]},"benefits":[],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["AI Agents","AI Development Tools"],"lifecycle":[{"event":"open","at":"2026-08-30T07:21:09Z"}],"visa":[{"country":"US","licensed_sponsor":true,"evidence":"H-1B filings in 12 months: 2","filings_12m":2,"filings_prev_12m":1,"green_card_filings_12m":0,"median_offered_wage_usd":97500,"route":null,"cap_exempt":false,"checked_at":"2026-10-15T11:24:14+00:00","sources":["US Department of Labor: LCA disclosure data (H-1B, H-1B1, E-3)"],"filings_for_role_12m":2}],"liveness":{"score":4,"band":"cold","label":"Long shot","p_open":1,"p_active":0.133,"p_room":0.28,"age_days":619,"expected_fill_days":26,"reasons":["conf:3","win:tail","crowd:"],"computed_at":"2026-10-16T05:45:00Z"},"pay":null,"html_url":"https://alion.io/job/letta-research-engineer-scientist-post-training","json_url":"https://alion.io/job/letta-research-engineer-scientist-post-training.json","meta":{"generated_at":"2026-10-16T19:58:54Z","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":434,"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":48112},"rest":"https://alion.io/mcp/rest/get_company?id=48112"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fletta-research-engineer-scientist-post-training"},{"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%2Fletta-research-engineer-scientist-post-training"},{"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%2Fletta-research-engineer-scientist-post-training"},{"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/letta-research-engineer-scientist-post-training\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fletta-research-engineer-scientist-post-training"}]}