{"id":127452,"url":"https://alion.io/job/1x-technologies-software-engineer-simulation","title":"Simulation Engineer - Physics Modeling","company":{"id":47967,"name":"1X Technologies","domain":"1x.tech","url":"https://alion.io/company/1x-technologies","size_band":"51-200","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":null},"role":"Robotics","role_family":"Robotics","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 Carlos, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":200000,"max":300000,"currency":"USD","period":"year","gross":null,"usd_annual":300000},"salary_estimate":null,"experience_years_min":5,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"C++","optional":false},{"name":"Isaac Sim","optional":false},{"name":"MuJoCo","optional":false},{"name":"PyBullet","optional":false},{"name":"Python","optional":false},{"name":"Sim-to-Real","optional":false},{"name":"Synthetic Data","optional":false},{"name":"JAX","optional":true}],"status":"live","first_seen_at":"2026-06-17T02:13:10Z","employer_posted_date":"2026-06-17","last_verified_at":"2026-10-17T07:13:28Z","board_verified":true,"closed_at":null,"days_open":122,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":122},"description":"About 1X\nWe're building humanoid robots that work in home - doing the chores, handling the tasks, and giving people their time back. Simple, but it's not.\nTo do this right, we have to solve robotics, AI, manufacturing - at the same time, at scale, in a form factor that has to be safe enough to live with your family. If you're inspired by this, you'll thrive here. We've been at this since 2014 and we're at the point where the hard problems are behind us and the hard work is in front of us.\nNEO is our flagship - a home robot designed to move, learn, and operate in the real world alongside real people. We're not demoing it - we're shipping it. We're excited to meet you, if this excites you.\nIf you've spent your career working on problems that matter and want to see them actually reach the world - this is that moment. We're scaling, we're hiring with intention, and we need people who want to build something that will genuinely change how humans spend their time - safely creating abundance for all.\nAbout the Team\nThe Simulation team builds the virtual environments and infrastructure that let 1X's AI team iterate on robot learning without being bottlenecked by real hardware. We construct physically realistic simulation worlds for NEO, scale synthetic data production, close the sim-to-real gap, and prototype new hardware virtually before it's manufactured. Our work is a force multiplier for every research and development team at 1X: the faster and more faithfully we can simulate NEO's world, the faster the whole company learns.\nYour Charter\nClose the gap between how NEO behaves in simulation and how it behaves in the world. You will make the simulator physically accurate enough that results earned in simulation hold up on hardware, building and validating the dynamics, material, and sensor models that decide whether a simulated result means anything. Every team that trains or evaluates against simulation is betting on the fidelity you deliver.\nKey Outcomes\nPhysical Accuracy: Improve contact dynamics, articulated body models, and actuator and transmission fidelity, driven by system identification data from real hardware and kept current as hardware changes.\n\nCompliant and Deformable Bodies: Model soft contact and structural compliance where rigid-body assumptions break down, so grasping and contact-rich behavior transfers instead of only working in simulation.\n\nSensing Realism: Model the sensing path as it actually behaves - noise, bias, dropout, latency, and sample timing - so a policy sees in simulation what it will see on the robot.\n\nMeasuring the Gap: Establish the benchmarks and real-robot comparisons that quantify sim-to-real error, so fidelity work is driven by evidence rather than intuition.\n\nRandomize or Model: Decide which discrepancies to model faithfully and which to randomize over, with ranges grounded in the spread measured across the real fleet.\n\nDeterminism and Reproducibility: Make runs reproducible given the same inputs, so a regression is a real regression and any failure can be replayed and debugged.\n\nThroughput and Environments: Optimize physics and rendering, and deliver the diverse environments and synthetic data pipelines that feed policy training and evaluation.\n\nKey Competencies\nPhysics Simulation Depth: Knows what makes a simulator physically accurate and computationally tractable, and how to tune contact dynamics and articulated body models for robot learning.\n\nSim-to-Real Judgment: Knows which differences between simulation and reality actually matter for policy transfer, and which can be absorbed by randomization.\n\nGrounded in Real Data: Validates fidelity against measurements from real robots rather than trusting a simulation that looks right.\n\nFleet Thinking: Treats unit-to-unit variation across real robots as something to measure and model, not average away, so simulation reflects the fleet rather than one nominal unit.\n\nPerformance Engineering: Optimizes physics and rendering pipelines for throughput, and reasons explicitly about the tradeoff between fidelity and speed.\n\nRigorous Infrastructure: Writes tested, maintainable simulation code other teams depend on, treating determinism and correctness of the stack as first-class concerns.\n\nTechnical Direction: Sets the approach for a problem area, defends tradeoffs across fidelity, throughput, and effort, and partners with the teams that depend on simulation.\n\nMinimum Requirements\nStrong programming in Python, C++, or similar languages, with experience building environments or benchmarks using robotics simulators (MuJoCo, PyBullet, Isaac Sim, or equivalent)\n\nDemonstrated experience improving simulation fidelity and closing the sim-to-real gap for behavior that had to work on physical hardware\n\nExperience modeling sensors and their failure modes in simulation, including noise, bias, latency, and dropout\n\nExperience improving the performance of physics simulators or rendering pipelines\n\nStrong testing practices for simulation stacks used in robot learning, including tests that verify physical correctness and catch regressions\n\n5+ years of relevant industry experience, or an advanced degree plus equivalent hands-on experience\n\nPreferred Skills\nExperience with system identification on real hardware, and with turning measured parameters into simulation models\n\nExperience with procedural environment generation or other techniques for scaling diverse simulation data production\n\nFamiliarity with differentiable simulation, learned or neural simulators, or GPU-accelerated physics such as Warp or JAX-based frameworks\n\nBackground in legged locomotion, dexterous manipulation, or contact-rich and deformable-body simulation\n\nCompensation\nSalary Range: $200,000 - $300,000 + Equity\n\nBenefits\nComprehensive medical, dental, and vision coverage\n\nGenerous paid time off, company holidays, and parental leave\n\n401(k) plan with company match (100% on the first 3% of contributions, 50% on the next 2%)\n\nFlexible Spending Accounts (FSA) and Health Savings Accounts (HSA) options\n\nCommuter benefits (transit and parking)\n\nShort-term and long-term disability, and life insurance\n\nEmployee Assistance Program (EAP) for mental health, financial, and personal support\n\nOnsite snacks and catered lunches\n\nEqual Opportunity Employer\n1X is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, gender, gender identity or expression, sexual orientation, national origin, ancestry, citizenship, age, marital status, medical condition, genetic information, disability, military or veteran status, justice system impact, or any other characteristic protected under applicable federal, state, or local law.","description_format":"text","description_chars":6740,"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","Life insurance","Parental leave"],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["Robotics AI","Humanoid Robots"],"lifecycle":[{"event":"open","at":"2026-06-17T02:13:10Z"}],"visa":[{"country":"US","licensed_sponsor":true,"evidence":"H-1B filings in 12 months: 12","filings_12m":12,"filings_prev_12m":0,"green_card_filings_12m":0,"median_offered_wage_usd":177500,"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":7}],"liveness":{"score":32,"band":"fade","label":"Fading","p_open":1,"p_active":0.732,"p_room":0.44,"age_days":122,"expected_fill_days":84,"reasons":["conf:2","velocity","win:tail","crowd:"],"computed_at":"2026-10-17T05:46:00Z"},"pay":{"stated_usd_annual":300000,"is_top_pay":true},"html_url":"https://alion.io/job/1x-technologies-software-engineer-simulation","json_url":"https://alion.io/job/1x-technologies-software-engineer-simulation.json","meta":{"generated_at":"2026-10-17T09:05:14Z","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":11936,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-18T00:00:00Z"}},"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":47967},"rest":"https://alion.io/mcp/rest/get_company?id=47967"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2F1x-technologies-software-engineer-simulation"},{"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%2F1x-technologies-software-engineer-simulation"},{"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%2F1x-technologies-software-engineer-simulation"},{"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/1x-technologies-software-engineer-simulation\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2F1x-technologies-software-engineer-simulation"}]}