{"id":15903,"url":"https://alion.io/job/langchain-senior-backend-software-engineer-ai-observability-evals-platform-langsmith","title":"Senior Backend Software Engineer, AI Observability & Evals Platform (SF)","company":{"id":4855,"name":"LangChain","domain":"langchain.com","url":"https://alion.io/company/langchain","size_band":"1001-5000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":{"grade":"A","score":90,"open_postings":48,"ghost_share":0,"stale_share":0.188,"repost_share":0,"time_to_fill_p50_days":72,"computed_at":"2026-10-17T05:46:00Z"}},"role":"Backend","role_family":"Backend","seniority":"senior","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","New York, United States","Boston, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":180000,"max":240000,"currency":"USD","period":"year","gross":null,"usd_annual":240000},"salary_estimate":null,"experience_years_min":5,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"AWS","optional":false},{"name":"Azure","optional":false},{"name":"ClickHouse","optional":false},{"name":"Cloudflare","optional":false},{"name":"GCP","optional":false},{"name":"Go","optional":false},{"name":"LangChain","optional":false},{"name":"LangGraph","optional":false},{"name":"LangSmith","optional":false},{"name":"Monday.com","optional":false},{"name":"PostgreSQL","optional":false},{"name":"Python","optional":false},{"name":"Redis","optional":false},{"name":"AI Agents","optional":true}],"status":"live","first_seen_at":"2026-01-08T12:04:40Z","employer_posted_date":"2026-01-08","last_verified_at":"2026-10-19T02:27:16Z","board_verified":true,"closed_at":null,"days_open":283,"trust":{"level":"stale","repost_count":0,"flags":["stale"],"days_open":283},"description":"About Us\nAt LangChain, our mission is to make intelligent agents ubiquitous. We build the foundation for agent engineering in the real world, helping developers move from prototypes to production-ready AI agents that teams can rely on. We began as widely adopted open-source tools and have grown to also offer a platform for building, evaluating, deploying, and operating agents at scale.\nWith $125M raised at Series B from IVP, Sequoia, Benchmark, CapitalG, and Sapphire Ventures, we’re at a stage where we’re continuing to develop new products, growth is accelerating, and all team members have meaningful impact on what we build and how we work together. LangChain is a place where your contributions can shape how this technology shows up in the real world.\nToday, our platform includes LangSmith (Observability, Evaluation, Deployment, Fleet, and Sandboxes), our open source frameworks (LangChain, LangGraph, and Deep Agents), and the newly launched LangSmith Engine for autonomous agent improvement. We have 100M+ monthly open source downloads, 6,000+ active LangSmith customers, and 5 of the Fortune 10 use LangSmith in production (+ 35% of the Fortune 500 overall), including teams at Klarna, Clay, Coinbase, Workday, Lyft, Cloudflare, Harvey, Rippling, Vanta, LinkedIn, Monday.com, Nvidia, and Bridgewater.\nAbout The Team\nThe LangSmith team owns and builds LangChain's core platform for observability, evaluation, and production reliability of AI systems. From tracing and annotation to run rules, evaluations, and beyond, this team owns LangSmith end-to-end. If you want to define what great AI observability looks like at production scale, this is where that work gets done.\nAbout The Role\nWe are looking for a Senior Backend Engineer to join us. In this role you will be building the backend systems that power LangChain’s observability and evals platform. You will work on the core services that allow developers to monitor and evaluate their AI applications at scale. While the focus is on backend feature development, familiarity with fullstack or frontend engineering, performance tuning, and debugging production issues would be extremely valuable.\nWhat You'll Do\nDesign, develop, and maintain backend services and APIs to support LangSmith’s tracing, monitoring, and evaluation workflows.\n\nCollaborate on architectural decisions to ensure systems are performant and maintainable.\n\nOptimize storage and query performance for high-volume observability and evaluation data.\n\nEnsure system reliability through strong testing, monitoring, and alerting practices.\n\nTroubleshoot and resolve production issues, performing root-cause analysis and implementing long-term fixes.\n\nCreate and maintain technical documentation, including system design and API references.\n\nWork closely with full-stack engineers, product managers, and product designers on rolling out new features.\n\nWhat You'll Bring\n5+ years of professional experience in backend engineering working on highly complex products\n\nProficiency in one or more backend languages/frameworks, ideally Python or Go\n\nStrong understanding of API design and building reliable data services.\n\nExperience with high-throughput or mission-critical systems.\n\nDemonstrated ability to optimize backend services for performance and reliability.\n\nExperience with database systems (Postgres, Redis, Clickhouse), and cloud platforms (AWS, GCP, Azure)\n\nStrong communication skills, with the ability to collaborate cross-functionally\n\nCustomer centricity and ownership mentality\n\nCompensation\nAnnual salary range: $180,000- $240,000\nCompensation Philosophy:\nWe offer competitive compensation that includes base salary, variable compensation for relevant roles, meaningful equity, benefits, and perks.\nWe are hiring for this role across a range of scope, and the compensation band reflects that. Your offer depends on what we learn about your impact, craft, leadership, and communication during the interview process. We will tell you early where you’re tracking and talk comp with you before offer stage. Team members in the EU, UK, and APAC receive locally competitive benefits aligned with regional norms and regulations.\nBenefits\nBenefits include medical, dental, and vision coverage, flexible vacation, a 401(k) plan, meals on in-office days in the US and more.","description_format":"text","description_chars":4312,"description_truncated":false,"requirements":{"experience_years_min":5,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":null,"security_clearance":false,"languages":[]},"benefits":["Equity"],"hiring_locations":[{"name":"United States","iso":"US","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["LLM & Generative AI","AI Agents","AI Development Tools","AI Evaluation & Observability"],"lifecycle":[{"event":"open","at":"2026-01-08T12:04:40Z"},{"event":"open","at":"2026-09-26T08:42:29Z"}],"visa":[{"country":"US","licensed_sponsor":true,"evidence":"H-1B filings in 12 months: 17","filings_12m":17,"filings_prev_12m":2,"green_card_filings_12m":0,"median_offered_wage_usd":172500,"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":15}],"liveness":{"score":12,"band":"cold","label":"Long shot","p_open":1,"p_active":0.424,"p_room":0.28,"age_days":281,"expected_fill_days":72,"reasons":["conf:0","velocity","win:tail","crowd:brand"],"computed_at":"2026-10-17T05:46:00Z"},"pay":{"stated_usd_annual":240000,"is_top_pay":true},"html_url":"https://alion.io/job/langchain-senior-backend-software-engineer-ai-observability-evals-platform-langsmith","json_url":"https://alion.io/job/langchain-senior-backend-software-engineer-ai-observability-evals-platform-langsmith.json","meta":{"generated_at":"2026-10-19T05:40:00Z","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":3462,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-20T00:00:00Z"}},"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":4855},"rest":"https://alion.io/mcp/rest/get_company?id=4855"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Flangchain-senior-backend-software-engineer-ai-observability-evals-platform-langsmith"},{"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%2Flangchain-senior-backend-software-engineer-ai-observability-evals-platform-langsmith"},{"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%2Flangchain-senior-backend-software-engineer-ai-observability-evals-platform-langsmith"},{"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/langchain-senior-backend-software-engineer-ai-observability-evals-platform-langsmith\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Flangchain-senior-backend-software-engineer-ai-observability-evals-platform-langsmith"}]}