{"id":3103980,"url":"https://alion.io/job/mobi-senior-frontend-engineer-3","title":"Senior Frontend Engineer","company":{"id":24963,"name":"Mobi","domain":"mobi.ai","url":"https://alion.io/company/mobi","size_band":null,"is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":null},"role":"Frontend","role_family":"Frontend","seniority":"senior","employment_type":"full_time","work_mode":"hybrid","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["Somerville, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":140000,"max":190000,"currency":"USD","period":"year","gross":null,"usd_annual":190000},"salary_estimate":null,"experience_years_min":10,"visa_sponsorship":false,"relocation_package":false,"has_equity":true,"technologies":[{"name":"Cypress","optional":false},{"name":"Git","optional":false},{"name":"JavaScript","optional":false},{"name":"Jest","optional":false},{"name":"Model Context Protocol","optional":false},{"name":"Playwright","optional":false},{"name":"React.js","optional":false},{"name":"Rest API","optional":false},{"name":"TypeScript","optional":false},{"name":"Vite","optional":false}],"status":"live","first_seen_at":"2026-10-22T14:48:31Z","employer_posted_date":"2026-10-22","last_verified_at":"2026-11-01T04:30:26Z","board_verified":true,"closed_at":null,"days_open":9,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":9},"description":"About Mobi.AI\nMobi partners with the world's leading travel brands to create AI experiences that change how people discover and book travel.\nBy combining deep AI expertise with more than a decade of experience in travel commerce, Mobi helps travel brands understand what travelers want, deliver more relevant experiences, and convert AI-driven intent into direct bookings. Our technology connects the intelligence of AI with the realities of travel-integrating with the systems brands already use while creating new opportunities to engage customers throughout their journey. We're building the infrastructure that will power the next generation of travel commerce.\nWorking at Mobi\nWe believe the best ideas emerge when diverse perspectives come together, so we’re building a team that truly reflects that belief. If you’re energized by complex challenges, inspired by working alongside thoughtful teammates, and passionate about building technology that enhances-rather than replaces-what makes us human, you’ll feel right at home here.\nOur work is centered on five core values:\nShow up, be you. We welcome every kind of thinker, maker, and teammate: quiet or bold, methodical or messy, with all their talents and quirks. Inclusion isn’t a checkbox-it’s how we connect, grow together, and do our best work.\n\nBe scrappy, stay steady. We’re resilient and quick on our feet, adapting with creativity and staying grounded when things shift.\n\nCreate transparency, collaborate better. We believe knowledge grows when it’s shared. Clear, open communication builds trust and strengthens collaboration.\n\nFoster community, be compassionate. We show up for our teammates, customers, and neighbors. Strong businesses grow from relationships built with care and grounded in shared effort.\n\nBuild thoughtfully, create impact. We design for clarity, build for scale, and measure success through real-world impact.\n\nAbout the Role\nAs a Senior Frontend Engineer at Mobi, you’ll own customer-facing features from defining the problem and making design trade-offs to implementation, release, and production support.\nWe’re looking for a curious engineer who can turn ambiguous customer needs into reliable, accessible experiences for AI-powered travel.\nYou’ll build interactive search and recommendation experiences, virtual concierge services, and data-rich dashboards. You’ll work directly with clients, designers, backend engineers, and AI engineers to scope solutions, explain trade-offs, and iterate on what users need.\nYou’ll build tool-driven interfaces for AI assistants and app integrations, including Model Context Protocol (MCP) apps. The work includes streaming and partial results, authentication and session continuity, and clear loading, error, and confirmation states.\nAI-assisted software development is essential to this role. You should be able to show how you use coding assistants and agents to implement, test, debug, and refine changes across an existing codebase, through professional or substantive project work. You remain accountable for the result: understanding the code, checking assumptions, and independently verifying correctness, security, accessibility, and maintainability.\nKey Responsibilities\nDesign, build, and maintain production React and TypeScript applications, making explicit trade-offs in component architecture, state management, and maintainability.\n\nTurn designs and prototypes into responsive, accessible interfaces, including keyboard navigation, screen reader support, and usable pending, error, and confirmation states.\n\nUse AI coding assistants and agents throughout the development lifecycle to accelerate delivery while maintaining high standards for correctness, accessibility, performance, and maintainability.\n\nWork with design, backend, and AI engineers to define UI contracts for tool calls, streaming, session state, and recoverable failures.\n\nMeasure and improve frontend performance, including responsiveness, rendering, and the user experience during slow or interrupted requests.\n\nStay current with front-end trends, tools, and emerging AI technologies.\n\nDebug production issues across browser rendering, application state, and API integration; use telemetry and reproducible cases to find root causes and prevent regressions.\n\nBuild and maintain deterministic unit, component, integration, and end-to-end tests for UI behavior and API contracts. Partner with AI and backend engineers on scenario-based evaluation of model-driven interactions, including partial results, failures, and user confirmations.\n\nDevelop and share effective AI-assisted workflows to improve engineering productivity and code quality.\n\nQualifications\nBachelor’s degree in Computer Science, Engineering, or related field-or equivalent practical experience.\n\nProficiency in HTML5, CSS3, JavaScript (ES6+).\n\nDeep practical experience with React, including component architecture, state management, and diagnosing rendering and performance issues.\n\nStrong practical TypeScript skills, including type-safe component and API contracts and the ability to work confidently in an existing codebase.\n\nExperience writing and maintaining reliable automated frontend tests with tools such as Playwright, Jest, or Cypress, including asynchronous behavior and failure cases.\n\nDemonstrated proficiency with AI coding assistants and agents, shown through professional or substantive project work that you can explain, test, and critically review.\n\nExperience directing AI tools through changes across multiple files in an existing codebase, including implementation, test generation, debugging, and refactoring.\n\nStrong judgment in evaluating AI-generated solutions: able to explain the code, verify its behavior, identify errors, and recognize when independent investigation or a different approach is needed.\n\nExperience integrating frontend applications with RESTful APIs and asynchronous services, including authentication, session state, and error recovery.\n\nUnderstanding of responsive design principles and cross-browser compatibility.\n\nExperience with build tools and version control (e.g., Next, Vite, Git).\n\nEvidence of independently shipping and supporting complex frontend features, explaining design tradeoffs, and collaborating effectively with designers, customers, and engineers.\n\nPreferred: Experience shipping AI-powered user interfaces.\n\nBonus: Understanding of MCP and response streaming.\n\nBenefits & Perks\nCompetitive Base Salary + Annual Bonus\n\nComprehensive Health Insurance (Medical, Dental, and Vision) for you and your family, covered mostly by the company.\n\nCompany-paid Disability and Life Insurance\n\nOptional Pet Insurance and Identity Theft Protection\n\nPaid Parental Leave (for all types of parents and families)\n\nEquity ownership in the company\n\n401k Plan\n\nUnlimited Paid Time Off + $1,000 Bonus for taking five consecutive days off\n\nFlexibility to work anywhere in the world for one month a year\n\nTuition Reimbursement\n\nCell Phone & Transportation Reimbursement\n\nLunch daily from local restaurants\n\nCozy office environment with a full kitchen, massage chairs, live plants, and much more!\n\nMobi hires those willing to work either full-time in office or on a hybrid schedule.\nEqual Opportunity\nWe are an equal opportunity employer; applicants, employees, and former employees are protected from employment discrimination and harassment of any type based on race, color, religion, sex (including pregnancy, sexual orientation, or gender identity), national origin, age, disability, protected veteran status and genetic information (including family medical history), or any other characteristic protected by federal, state or local laws.\nPay Transparency\nThe base salary range for this US full-time position is between $140,000 - $190,000 and is eligible for an annual company bonus, subject to standard withholding and applicable taxes. All candidates receive equity (ISO) and access to a comprehensive benefits offering. The base salary range reflects the minimum and maximum targets for candidates. The following factors are considered when determining the compensation offered: work location, skills, experience, and any relevant education or training. The Recruiter or Hiring Manager can share more about the specific salary range with you during the recruitment process and answer any questions you have.","description_format":"text","description_chars":8344,"description_truncated":false,"requirements":{"experience_years_min":10,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"bachelor","optional":false},"security_clearance":false,"languages":[]},"benefits":["401k plan","Equity","Health insurance","Life insurance","Parental leave"],"hiring_locations":[{"name":"United States","iso":"US","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["Industrial AI"],"lifecycle":[{"event":"open","at":"2026-10-22T18:21:44Z"}],"visa":[],"liveness":{"score":89,"band":"hot","label":"Hiring now","p_open":1,"p_active":0.885,"p_room":1,"age_days":9,"expected_fill_days":28,"reasons":["conf:1","velocity","win:early"],"computed_at":"2026-11-01T06:10:25Z"},"pay":{"stated_usd_annual":190000,"is_top_pay":true},"html_url":"https://alion.io/job/mobi-senior-frontend-engineer-3","json_url":"https://alion.io/job/mobi-senior-frontend-engineer-3.json","meta":{"generated_at":"2026-11-01T07:13:34Z","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":11268,"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":24963},"rest":"https://alion.io/mcp/rest/get_company?id=24963"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fmobi-senior-frontend-engineer-3"},{"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%2Fmobi-senior-frontend-engineer-3"},{"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%2Fmobi-senior-frontend-engineer-3"},{"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/mobi-senior-frontend-engineer-3\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fmobi-senior-frontend-engineer-3"}],"agent":{"mcp":"https://alion.io/mcp/jobs","mcp_open":"https://alion.io/mcp/open","next":[{"tool":"get_job","arguments":{"id":3103980}},{"tool":"search_jobs","arguments":{"company":"mobi.ai","detail":"compact"}},{"tool":"match_people","arguments":{"job_id":3103980},"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"}}