{"id":2549276,"url":"https://alion.io/job/thirdfort-senior-software-engineer","title":"Senior Software Engineer","company":{"id":172476,"name":"Thirdfort","domain":"thirdfort.com","url":"https://alion.io/company/thirdfort","size_band":"1-10","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Lever","truth_index":null},"role":"Backend","role_family":"Backend","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":["London, United Kingdom"],"countries":["GB"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":null,"max":100000,"currency":"GBP","period":"year","gross":null,"usd_annual":131489},"salary_estimate":null,"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"AWS","optional":false},{"name":"GCP","optional":false},{"name":"Go","optional":false},{"name":"React.js","optional":false},{"name":"TypeScript","optional":false},{"name":"Claude Code","optional":true},{"name":"Copilot","optional":true},{"name":"Cursor","optional":true},{"name":"JavaScript","optional":true}],"status":"live","first_seen_at":"2026-09-18T15:16:38Z","employer_posted_date":"2026-09-18","last_verified_at":"2026-10-15T04:47:20Z","board_verified":true,"closed_at":null,"days_open":26,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":26},"description":"We’re on a mission to protect society from fraud and money laundering. We’ve already protected over 3 million people through life’s big transactions.\nFraud and regulation are rising, costing the UK economy over £100bn every year; this makes it more difficult for businesses to protect themselves and their clients - individuals like you and me - from fraud and money laundering.\nOur co-founders Olly and Jack were led to this area when a friend was defrauded of £25K when buying their first property. At the time, anti-fraud technology didn’t exist, which meant that completing the anti-fraud checks required in these processes was largely manual. These big life moments should be exciting, but instead are often confusing and scary due to the painful process of completing these paper-based checks and the risk of fraud.\nThirdfort helps businesses to facilitate these anti fraud checks so that individuals know they can transact safely and seamlessly with professionals during these big transactions. Our anti-fraud platform provides a secure way for professionals in regulated sectors like Lawyers, Estate Agents and Accountants to transfer funds and verify sensitive information through app based document checks, facial recognition and open banking.\nOver 1,500 businesses now trust Thirdfort to verify their clients. We are FCA regulated and have raised over $33m in capital from leading Fintech investors Breega and Element Ventures, as well as the founders of Zoopla, Funding Circle, Comply Advantage, Tessian, Fenergo and Fidel.\nAbout the role:\nYou'll join Thirdfort at an exciting moment for Tenant Referencing. We're rebuilding the product from the ground up, moving it off a legacy platform onto Thirdfort's strategic engineering platform (Go, Temporal-based workflows, cloud-native). You'll be one of the first permanent engineers on a newly-formed squad, with real scope to shape how tenant referencing gets architected and make technical calls on a live migration. It matters beyond the tech, too. Tenant referencing is where our fraud-prevention mission meets something that matters to people directly: renting a home.\nWe're looking for someone who takes ownership, is comfortable without a fully mature spec, and is pragmatic about tooling, including using AI where it helps them move faster.\nFor this role, we would love this person to be able to join us in our London office two times a week as being together as a team is valuable for us but ultimately, we trust our team to decide what works best for them.\nYou will achieve your mission as our Senior Software Engineer by:\nHelping lead the rebuild of our tenant referencing product, migrating it from our legacy platform onto Thirdfort's strategic engineering platform (Go, Temporal-based workflows), working across both systems during the transition\nDesigning and building backend services and APIs that power tenant referencing checks, and contributing to our frontend (React/TypeScript) and mobile platforms when needed\nMaking independent architecture and delivery decisions on a fast-moving, still-forming squad, working closely with our Product & Tech Lead\nUpholding engineering quality through testing, observability, and code review, as we build permanent engineering ownership into the team\nPartnering closely with Ops and Support to understand real tenant referencing workflows and translating that understanding into good technical decisions\nUsing modern engineering practices, including AI-assisted development, to build new check types and features quickly without sacrificing quality\nMentoring and uplifting engineering practices across the squad as it grows\nYou may be right for this role if you:\nHard requirements:\nHave strong backend service experience in a modern programming language, with the ability to ramp up quickly in Go\nHave experience designing, building, and integrating APIs\nHave experience working in cloud environments (AWS and/or GCP)\nHave taken ownership of ambiguous technical problems and seen them through with minimal oversight\nNice to haves:\nHave experience with workflow orchestration or event-driven systems (e.g. Temporal)\nAre comfortable using AI coding tools (e.g. Copilot, Cursor, Claude Code) as part of your everyday workflow\nHave experience working across a legacy-to-modern platform migration\nHave some experience with React/TypeScript and/or mobile development\n“Studies show that women and other less represented groups are less likely to apply for roles unless they meet every requirement. We believe in building a diverse team, valuing different skills and experiences and so if you don’t think you have all the requirements listed here but feel this could be a role and environment you’d thrive in, we would still love for you to apply.\"\nOur Benefits:\nWe've created our benefits package to reflect Thirdfort's mission and values. Everything we do is designed to build on trust, and we extend this promise to our team by investing in their physical, mental, and financial security to support them through life's big moments. Ultimately, our benefits exist to empower our people, ensuring everyone feels deeply supported, trusted, and equipped to do their best work.\nWhen you join Thirdfort, you'll get immediate access to our employee benefits package that aims to support you across these areas:\nCompensation: up to £100,000 base salary\nLocation - London Office - twice per week\nShare options for all UK employees\nAnnual leave allowance of 26 days, increasing to 30 with tenure and the option to buy additional days\nUncapped personal development budget\nFlexible working hours\nPrivate healthcare (AXA)\nEnhanced parental and sick leave\nWe're committed to building an inclusive, equitable and diverse culture where everyone has a chance to make a difference. We're purposefully building a team of problem-solvers that reflect our values, which is why we hire from all backgrounds. If you're a curious, kind individual who takes ownership, you'll be a great Thirdforter.\n If you require any reasonable adjustments during the application or interview process, please let your dedicated Talent Partner know and we'll do our best to accommodate.","description_format":"text","description_chars":6158,"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":["Annual leave","Flexible schedule","Stock options"],"hiring_locations":[{"name":"United Kingdom","iso":"GB","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["Identity Management","RegTech, AML & Compliance"],"lifecycle":[{"event":"open","at":"2026-10-14T17:35:34Z"}],"visa":[{"country":"GB","licensed_sponsor":true,"evidence":"Licensed UK visa sponsor (Skilled Worker)","filings_12m":null,"filings_prev_12m":null,"green_card_filings_12m":null,"median_offered_wage_usd":null,"route":"Skilled Worker","cap_exempt":false,"checked_at":"2026-10-15T06:21:15+00:00","sources":["UK Home Office: register of licensed sponsors (workers)"],"filings_for_role_12m":0}],"liveness":{"score":35,"band":"fade","label":"Fading","p_open":1,"p_active":0.635,"p_room":0.55,"age_days":26,"expected_fill_days":23,"reasons":["conf:0","win:tail"],"computed_at":"2026-10-15T05:46:00Z"},"pay":{"stated_usd_annual":131489,"is_top_pay":false},"html_url":"https://alion.io/job/thirdfort-senior-software-engineer","json_url":"https://alion.io/job/thirdfort-senior-software-engineer.json","meta":{"generated_at":"2026-10-15T08:32:10Z","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":12794,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-16T00:00:00Z"}},"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":172476},"rest":"https://alion.io/mcp/rest/get_company?id=172476"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fthirdfort-senior-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%2Fthirdfort-senior-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%2Fthirdfort-senior-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/thirdfort-senior-software-engineer\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fthirdfort-senior-software-engineer"}]}