{"id":498865,"url":"https://alion.io/job/mlssoccer-principal-aiml-engineer-semantic-data","title":"Principal AI/ML Engineer, Semantic Data","company":{"id":20301,"name":"mlssoccer","domain":"mlssoccer.com","url":"https://alion.io/company/mlssoccer","size_band":"501-1000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"iCIMS","truth_index":null},"role":"AI/ML","role_family":"AI/ML","seniority":"lead","employment_type":null,"work_mode":"hybrid","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["New York, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":200000,"max":235000,"currency":"USD","period":"year","gross":null,"usd_annual":235000},"salary_estimate":null,"experience_years_min":8,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Embeddings","optional":false},{"name":"Hybrid Search","optional":false},{"name":"Knowledge Graph","optional":false},{"name":"LLM","optional":false},{"name":"LLM Guardrails","optional":false},{"name":"Python","optional":false},{"name":"RAG","optional":false},{"name":"SQL","optional":false},{"name":"Structured Outputs","optional":false},{"name":"AWS","optional":true},{"name":"Databricks","optional":true},{"name":"Feature Store","optional":true},{"name":"Snowflake","optional":true}],"status":"live","first_seen_at":"2026-09-07T08:51:36Z","employer_posted_date":"2026-09-19","last_verified_at":"2026-11-01T08:43:43Z","board_verified":true,"closed_at":null,"days_open":55,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":55},"description":"Overview\nMajor League Soccer is building advanced AI and data platforms to power fan intelligence, personalization, and data-driven decisioning across the organization.\nThe Principal AI/ML Engineer, Semantic Data will design and build the semantic intelligence layer that enables consistent understanding of fan data, business concepts, and operational workflows across MLS systems.\nThis role combines semantic data systems with applied LLM engineering to build grounded, production-grade AI capabilities.\nThis is a systems engineering role responsible for building and scaling real-world AI infrastructure, including knowledge graphs, retrieval systems, and LLM-powered applications.\nResponsibilities\nAI & Knowledge Systems Development\nDesign and implement embedding pipelines across fan data, content, metadata, and behavioral signals\nBuild metadata and enrichment systems that normalize and structure enterprise data for AI use\nDevelop knowledge bases and retrieval systems using vector databases and hybrid search architectures\nCreate context assembly pipelines combining structured data, documents, APIs, and historical outputs\nEnable AI systems to operate on unified semantic representations rather than raw data\nSemantic Layer & Knowledge Graphs\nArchitect and manage knowledge graphs representing fan, content, and business entity relationships\nDefine and maintain a semantic layer standardizing metrics, features, and business concepts\nDesign ontologies, taxonomies, and entity models for fan behavior and identity\nImplement graph-based reasoning and enrichment workflows\nEnsure semantic consistency across analytics, ML, and operational systems\nLLM & Applied AI Systems\nDesign and build retrieval-augmented generation (RAG) systems grounded in semantic data\nIntegrate LLMs for reasoning over structured and unstructured data\nDevelop pipelines translating natural language into structured outputs such as queries and analytical tasks\nBuild and optimize context pipelines improving LLM grounding and factual accuracy\nEvaluate and integrate open-weight models for domain-specific reasoning\nFine-tune or adapt models using parameter-efficient techniques\nSupport deployment of LLM systems in private or on-prem GPU environments\nOptimize inference workflows for latency, cost, and scalability\nEnable LLM-driven workflows that reason over semantic data and retrieval systems\nPlatform & Infrastructure\nBuild scalable, production-grade services and APIs for semantic and AI systems\nWork with vector and graph databases to support retrieval and reasoning\nIntegrate structured data, documents, APIs, and model outputs\nPartner with data engineering on batch and real-time pipelines\nEnsure systems meet performance and reliability requirements\nGovernance, Evaluation & Reliability\nDesign evaluation frameworks for retrieval quality and LLM output correctness\nMonitor system performance, relevance, and model behavior\nEstablish guardrails for explainability, traceability, and data attribution\nEnsure safe and reliable generation of structured outputs\nMitigate risks related to bias, data leakage, and inconsistencies\nCross-Functional Collaboration\nCollaborate with product, analytics, and engineering teams on AI use cases\nTranslate business problems into systems combining semantic data and LLM reasoning\nPartner with ML teams to improve model performance through better grounding\nMentor engineers and establish best practices\nQualifications\nMaster’s degree or higher in computer science, engineering, or related field\n8-10+ years of experience in ML engineering, data systems, or applied AI\nStrong expertise in Python, SQL, and production software engineering\nDeep experience with semantic data modeling, ontologies, and entity resolution\nHands-on experience with embeddings, vector search, and retrieval systems\nExperience building and deploying LLM-powered systems including RAG\nExperience building production-grade AI systems at scale\nStrong understanding of distributed systems and data architecture\nPreferred Qualifications\nExperience with knowledge graphs and graph databases\nExperience designing semantic layers or feature stores\nExperience with open-weight LLMs and model adaptation\nFamiliarity with on-prem or private GPU deployments\nExperience with modern data platforms (AWS, Snowflake, Databricks)\nBackground in marketing analytics, personalization, or customer data platforms\nTotal Rewards\nMajor League Soccer offers a competitive starting base salary of $200,000-$235,000, based on individual qualifications, market financials, and operational business needs. We are committed to providing a Total Rewards package that attracts, supports, engages, and retains talent. Our benefits package includes comprehensive medical, dental, and vision coverage, a $500 wellness reimbursement, and generous Holiday and PTO schedule to promote work-life balance. We also prioritize career and professional development, offering on-the-job training, feedback, and ongoing educational opportunities.\nMajor League Soccer believes in the value of in-person collaboration to support teamwork, creativity, and connection. Employees in this role are expected to work a four (4) day in-office schedule, with the flexibility to work remotely one (1) day each week, based on business and department needs.\nMajor League Soccer is an equal opportunity employer. Employment decisions are made without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability, genetic information, protected veteran status, or any other characteristic protected by applicable federal, state, or local law.\nMajor League Soccer is committed to providing reasonable accommodations to individuals with disabilities throughout the application and hiring process, as well as during employment. Applicants who require an accommodation may contact Human Resources to request assistance.\nJoin our team and help support the growth and success of Major League Soccer.","description_format":"text","description_chars":5999,"description_truncated":false,"requirements":{"experience_years_min":8,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"master","optional":false},"security_clearance":false,"languages":[]},"benefits":["Professional development"],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["Sports Media","Sports Organizations"],"lifecycle":[{"event":"open","at":"2026-09-07T08:51:36Z"}],"visa":[],"liveness":{"score":19,"band":"cold","label":"Long shot","p_open":1,"p_active":0.54,"p_room":0.35,"age_days":54,"expected_fill_days":23,"reasons":["conf:1","win:tail"],"computed_at":"2026-11-01T06:10:25Z"},"pay":{"stated_usd_annual":235000,"is_top_pay":true},"html_url":"https://alion.io/job/mlssoccer-principal-aiml-engineer-semantic-data","json_url":"https://alion.io/job/mlssoccer-principal-aiml-engineer-semantic-data.json","meta":{"generated_at":"2026-11-01T09:16:04Z","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":14365,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-11-02T00:00:00Z"}},"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":20301},"rest":"https://alion.io/mcp/rest/get_company?id=20301"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fmlssoccer-principal-aiml-engineer-semantic-data"},{"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%2Fmlssoccer-principal-aiml-engineer-semantic-data"},{"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%2Fmlssoccer-principal-aiml-engineer-semantic-data"},{"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/mlssoccer-principal-aiml-engineer-semantic-data\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fmlssoccer-principal-aiml-engineer-semantic-data"}],"agent":{"mcp":"https://alion.io/mcp/jobs","mcp_open":"https://alion.io/mcp/open","next":[{"tool":"get_job","arguments":{"id":498865}},{"tool":"search_jobs","arguments":{"company":"mlssoccer.com","detail":"compact"}},{"tool":"match_people","arguments":{"job_id":498865},"note":"people open to offers who fit this vacancy"}],"note":"The same data through MCP tools: https://alion.io/mcp/open needs no sign-in (compact searches, postings, people); https://alion.io/mcp with an Alion account has everything. Docs: https://alion.io/developers"}}