{"id":770580,"url":"https://alion.io/job/fin-senior-full-stack-software-engineer","title":"Senior Full-Stack Software Engineer","company":{"id":7591,"name":"Fin","domain":"fin.tech","url":"https://alion.io/company/fin","size_band":"1-10","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":{"grade":"C","score":58,"open_postings":10,"ghost_share":0.7,"stale_share":0,"repost_share":0,"time_to_fill_p50_days":53,"computed_at":"2026-10-16T05:45:00Z"}},"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":["New York, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":125000,"max":250000,"currency":"USD","period":"year","gross":null,"usd_annual":250000},"salary_estimate":null,"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Node JS","optional":false},{"name":"React Native","optional":false},{"name":"Rust","optional":false},{"name":"Stripe","optional":false},{"name":"TypeScript","optional":false},{"name":"Expo","optional":true},{"name":"JavaScript","optional":true},{"name":"React.js","optional":true},{"name":"Solana","optional":true}],"status":"live","first_seen_at":"2025-12-03T14:53:06Z","employer_posted_date":"2025-12-03","last_verified_at":"2026-10-16T11:55:00Z","board_verified":true,"closed_at":null,"days_open":317,"trust":{"level":"ghost","repost_count":0,"flags":["stale","company_stale"],"days_open":316},"description":"About Fin\nFin is a next-generation payments platform built for high-value, global, and instant transactions. We are a Series A-stage company backed by Sequoia, Circle, and other notable investors. Powered by stablecoins, Fin enables users and businesses to move millions of dollars in seconds - whether to other Fin users, directly into bank accounts, or across crypto rails. By combining the speed of crypto with the reliability and trust of traditional finance, Fin reimagines how money moves worldwide. If banks and payment products were reinvented today, they would look like Fin.\nAbout the role\nWe are looking for a Senior Full Stack Engineer to join the early team and help define how money moves on Fin. You will work closely with the CEO, CTO, and a small group of senior engineers to design and ship core product experiences, integrate with payment partners (Stripe, PayPal, on and off ramps, banks), and build the systems that let Fin handle millions of transactions safely and reliably.\nThis is a highly autonomous role where you own projects end to end, from shaping the spec to deployment, and see your work in the hands of real users quickly. If you care about building simple products on top of complex systems and are excited about fixing how global payments work, we would love to talk.\nWe value your time: our process focuses on practical system design and architectural discussions, not LeetCode grinding or unpaid take-home assignments.\nWhat you will do\nDesign, build, and ship full stack features across our web and mobile surfaces, from APIs and services to polished user interfaces.\n\nOwn projects end to end: work with product and leadership to scope requirements, design systems, implement, test, and ship to production.\n\nIntegrate third party payment and financial APIs, including processors, on and off ramps, compliance tooling, and identity providers.\n\nBuild scalable, high performance services that handle real money movement with strong reliability and observability.\n\nMaintain a high bar for code quality through clean abstractions, tests, and thoughtful code review.\n\nCollaborate closely with product, design, and operations so that what we ship feels simple for users even when the underlying system is complex.\n\nWhat you need to be successful\nDeep experience with TypeScript and Node.js. We are mostly a TS shop with some pockets of Rust.\n\nProduction experience with React Native. Bonus points if you are familiar with the Expo ecosystem and modern mobile build pipelines.\n\nExperience owning complex product changes from idea through launch, not just implementing narrow tickets.\n\nDeep comfort debugging across the stack, from database and infrastructure issues to front end performance problems.\n\nSolid understanding of security best practices, particularly around authentication, authorization, and handling sensitive data.\n\nA strong sense of code quality, including testing, readability, and maintainability in a fast moving environment.\n\nClear written and verbal communication, and an ability to work closely with non engineering partners.\n\nHigh tolerance for ambiguity and the necessary shifting targets that exist in an early stage start up environment.\n\nBonus points\nExperience in EITHER traditional fintech integrations (Stripe, Plaid, ACH rails) OR blockchain infrastructure (especially Solana in a production environment).\n\nPrior startup experience where you were an early engineer and had meaningful product ownership.","description_format":"text","description_chars":3463,"description_truncated":false,"requirements":{"experience_years_min":null,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":null,"security_clearance":false,"languages":[]},"benefits":[],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["Blockchain & Crypto","Payment Processing & Gateways","Stablecoins"],"lifecycle":[{"event":"open","at":"2026-09-11T21:27:04Z"},{"event":"open","at":"2026-09-25T21:52:39Z"}],"visa":[],"liveness":{"score":3,"band":"cold","label":"Long shot","p_open":1,"p_active":0.119,"p_room":0.28,"age_days":316,"expected_fill_days":53,"reasons":["conf:3","stale_co","ghost","win:tail","crowd:"],"computed_at":"2026-10-16T05:45:00Z"},"pay":{"stated_usd_annual":250000,"is_top_pay":true},"html_url":"https://alion.io/job/fin-senior-full-stack-software-engineer","json_url":"https://alion.io/job/fin-senior-full-stack-software-engineer.json","meta":{"generated_at":"2026-10-16T15:47:26Z","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":1,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-17T00:00:00Z"}},"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":7591},"rest":"https://alion.io/mcp/rest/get_company?id=7591"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Ffin-senior-full-stack-software-engineer"},{"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%2Ffin-senior-full-stack-software-engineer"},{"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%2Ffin-senior-full-stack-software-engineer"},{"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/fin-senior-full-stack-software-engineer\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Ffin-senior-full-stack-software-engineer"}]}