{"id":3116212,"url":"https://alion.io/job/exa-software-engineer-knowledge-engine-query-engine","title":"Software Engineer, Knowledge Engine – Query Engine","company":{"id":13137,"name":"Exa","domain":"exa.ai","url":"https://alion.io/company/exa","size_band":"501-1000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":{"grade":"B","score":84,"open_postings":22,"ghost_share":0,"stale_share":0.455,"repost_share":0,"time_to_fill_p50_days":72,"computed_at":"2026-10-24T06:02:35Z"}},"role":"Backend","role_family":"Backend","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":{"min":180000,"max":350000,"currency":"USD","period":"year","gross":null,"usd_annual":350000},"salary_estimate":null,"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"C++","optional":false},{"name":"Cursor","optional":false},{"name":"Exa","optional":false},{"name":"Knowledge Graph","optional":false},{"name":"Rust","optional":false},{"name":"Time Series","optional":false}],"status":"live","first_seen_at":"2026-10-22T19:55:29Z","employer_posted_date":"2026-10-22","last_verified_at":"2026-10-24T09:03:38Z","board_verified":true,"closed_at":null,"days_open":1,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":1},"description":"Exa is an applied AI lab building a search engine unlike the world has ever seen. We build massive-scale infra to crawl the entire web, train state-of-the-art embedding models to process it, and design super high performant vector databases to retrieve over it. We now power search for Cursor, Cognition, HubSpot, and over 400,000 developers and have raised $350m from Lightspeed, Benchmark, and a16z.\nOur ultimate goal is to build perfect search over all the world's information, far beyond Google. If you want to build massive-scale ML systems that will define the way the new AI world consumes information, this is the place for you.\nThe Knowledge Platform team builds Exa's knowledge engine. We continuously synthesize information from across the web and beyond into one of the world's largest open-domain knowledge graphs, with hundreds of billions of evidence-backed claims. The work has two halves: construction pipelines that decide what to trust, and retrieval engines that decide how best to search it. Our goal is to give agents answers to any factual question about the world with unprecedented precision and completeness.\nIn this role, you'll own the query engine that searches hundreds of billions of claims across a variety of retrieval backends, from a distributed graph database to vector, full-text, time-series and geospatial indexes.\nThis is greenfield work with a massive scope. No off-the-shelf system answers precise questions over hundreds of billions of evidence-backed claims at agent speed, so you'll make foundational decisions, from storage layout and indexing across engines to the query language and the planner that routes work between them, that every query depends on.\nWhat you'll do\nOwn storage and indexing across backends: data layout, partitioning and indexes for graph, vector, full-text, time-series and geospatial retrieval, with bulk snapshot builds and live ingest that never take the system down.\n\nDecide how best to search: cost-based planning from cardinality estimates that chooses, for each question, which backends to use, in what order and how to join their results, executed as traversals, retrievals, filters and aggregations in one plan.\n\nMake it fast at scale: serve thousands of queries per second, profiling and cutting p50/p99 latency, memory and cost per query under high concurrent load, from on-disk layout to network fan-out.\n\nKeep answers consistent while the data converges: the graph is fed by live updates and bulk snapshots at once and is eventually consistent by design, so you'll own what a query may see while it converges: consistent snapshot promotion, ordered application of live updates and stable pagination across versions.\n\nMeasure precision and completeness: end-to-end checks every deployment must pass, plus evals and metrics that show when a plan returns wrong results or misses ones it should have found.\n\nWhat we're looking for\nYou've worked deep inside a distributed database, query engine, search engine or storage system.\n\nStrong grasp of indexing, query planning and optimization, and storage formats.\n\nSolid grasp of distributed systems fundamentals: consensus, replication, sharding and fault tolerance.\n\nStrong in a systems language (Go, Rust or C++).\n\nYou profile before you optimize, and you've shipped measured latency wins in production.\n\nYou obsess over correctness, reliability and data quality as much as scale.\n\nBonus\nGraph databases, or combining vector, full-text, time-series and geospatial retrieval\n\nCompilers, query language design or cost-based optimizers\n\nExample projects\nBuild a system that retrieves and reasons over everything known about any company or person in the world, answering any factual question precisely and completely.\n\nAnswer precise multi-hop questions over hundreds of billions of claims at thousands of QPS with interactive latency.\n\nBuild a planner that picks the right mix of graph, vector, full-text and geospatial retrieval for any question, and proves it chose well.\n\nMake new knowledge queryable seconds after it's synthesized, without ever serving an inconsistent result.\n\nLogistics\nLocation: This is an in-person opportunity in San Francisco.\n\nVisas: We're happy to sponsor international candidates (e.g., STEM OPT, OPT, H1B, O1, E3). While we cannot guarantee your visa, we have historically been successful in sponsoring candidates from all over the world. If you receive an offer, our team will work hard to get you a visa.\n\nBenefits: We offer premium healthcare benefits (medical, dental, vision), fertility benefits, 16 weeks of fully paid parental leave for all new parents, and a monthly wellness stipend to all of our employees.\n\nExa is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, creed, color, religion, sex, sexual orientation, gender identity or expression, national origin, disability, age, veteran status, marital status, pregnancy or related conditions, criminal histories consistent with applicable law, or any other basis protected by applicable law.\nExa is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, creed, color, religion, sex, sexual orientation, gender identity or expression, national origin, disability, age, veteran status, marital status, pregnancy or related conditions, criminal histories consistent with applicable law, or any other basis protected by applicable law.","description_format":"text","description_chars":5485,"description_truncated":false,"requirements":{"experience_years_min":null,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"phd","optional":false},"security_clearance":false,"languages":[]},"benefits":["Parental leave"],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["Search Engines","Vector Search & RAG","AI Search","Web Scraping & Proxy Networks"],"lifecycle":[{"event":"open","at":"2026-10-22T22:12:37Z"}],"visa":[],"liveness":{"score":90,"band":"hot","label":"Hiring now","p_open":1,"p_active":0.903,"p_room":1,"age_days":1,"expected_fill_days":72,"reasons":["conf:1","velocity","win:early"],"computed_at":"2026-10-24T06:02:35Z"},"pay":{"stated_usd_annual":350000,"is_top_pay":true},"html_url":"https://alion.io/job/exa-software-engineer-knowledge-engine-query-engine","json_url":"https://alion.io/job/exa-software-engineer-knowledge-engine-query-engine.json","meta":{"generated_at":"2026-10-24T11:44:41Z","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":16779,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-25T00:00:00Z"}},"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":13137},"rest":"https://alion.io/mcp/rest/get_company?id=13137"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fexa-software-engineer-knowledge-engine-query-engine"},{"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%2Fexa-software-engineer-knowledge-engine-query-engine"},{"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%2Fexa-software-engineer-knowledge-engine-query-engine"},{"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/exa-software-engineer-knowledge-engine-query-engine\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fexa-software-engineer-knowledge-engine-query-engine"}]}