{"id":1238769,"url":"https://alion.io/job/sparkles-founding-engineer-london","title":"Founding Engineer (London)","company":{"id":2144134,"name":"Sparkles","domain":"sparkles.dev","url":"https://alion.io/company/sparkles-dev","size_band":"11-50","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Work at a Startup","truth_index":null},"role":"Backend","role_family":"Backend","seniority":null,"employment_type":"full_time","work_mode":"on_site","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":100000,"max":150000,"currency":"GBP","period":"year","gross":null,"usd_annual":198523},"salary_estimate":null,"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":true,"technologies":[{"name":"Claude Code","optional":false},{"name":"Cursor","optional":false},{"name":"Figma","optional":false},{"name":"OpenAI Codex","optional":false},{"name":"TypeScript","optional":false},{"name":"Anthropic","optional":true},{"name":"Cloudflare","optional":true},{"name":"OpenAI","optional":true}],"status":"live","first_seen_at":"2026-09-25T16:29:57Z","employer_posted_date":"2026-09-25","last_verified_at":"2026-10-12T15:32:15Z","board_verified":true,"closed_at":null,"days_open":17,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":17},"description":"Location: London · In-person · Full-time\nwith relocation to San Francisco\nWe're hiring a founding engineer who moves fast, cares about craft, and wants real ownership from day one. You'll build side by side with the founders, in person in London, from day one.\nYou should already use AI tools by default - pushing Cursor, Claude Code, Codex, and agent workflows hard, judging output critically, and moving faster without lowering the bar.\nWhat you'll own\nBuild and ship core product features end to end.\nTalk to users constantly, find bottlenecks, and ship fixes fast.\n\nSuggest new features, new products, and new internal tooling.\nHelp set the engineering bar, architecture, and pace of the company.\nThis is not a role where you can coast. It requires deep ownership, agency, and responsibility.\nWhat we're looking for\nStrong TypeScript and React skills.\nRoughly 1-5 years shipping real product software is a good baseline, but we'll flex for someone unusually strong.\nAbility to build full-stack product features with high autonomy.\nStrong product instincts and a bias toward outcomes.\nHigh agency: you notice problems, propose solutions, and drive things to completion.\nGood design taste. You can make sensible UI/product decisions, and Figma fluency is a plus.\n\nClear communication and strong judgment.\nComfort with ambiguity and a founder-speed environment.\nHeavy AI-tool usage as part of your real workflow, not as a novelty.\nStrong pluses\nExperience with Cloudflare Workers, Durable Objects, service bindings, realtime systems, or collaborative/live product surfaces.\nExperience building devtools.\nExperience building sandboxed or safety-sensitive systems.\nSparkles was founded by Dan, who dropped out of University College London and previously worked with the former CTO of Monzo at Iterate.com. We raised $3.5M, backed by Y Combinator, Moonfire Ventures, and angels from OpenAI, Anthropic, a16z, General Catalyst, Cloudflare, and others.\nScreening call\nTechnical interview\nWork trial with an offer within 24 hours","description_format":"text","description_chars":2023,"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":true,"industries":["Code Intelligence","AI Development Tools"],"lifecycle":[{"event":"open","at":"2026-09-25T16:29:57Z"}],"visa":[],"liveness":{"score":65,"band":"ok","label":"Likely open","p_open":1,"p_active":0.651,"p_room":1,"age_days":16,"expected_fill_days":69,"reasons":["conf:3","win:early"],"computed_at":"2026-10-12T06:55:09Z"},"pay":{"stated_usd_annual":198523,"is_top_pay":true},"html_url":"https://alion.io/job/sparkles-founding-engineer-london","json_url":"https://alion.io/job/sparkles-founding-engineer-london.json","meta":{"generated_at":"2026-10-12T17:36:31Z","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":28313,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-13T00:00:00Z"}},"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":2144134},"rest":"https://alion.io/mcp/rest/get_company?id=2144134"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fsparkles-founding-engineer-london"},{"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%2Fsparkles-founding-engineer-london"},{"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%2Fsparkles-founding-engineer-london"},{"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/sparkles-founding-engineer-london\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fsparkles-founding-engineer-london"}]}