{"id":503954,"url":"https://alion.io/job/voize-senior-backend-engineer-kotlin-mfd-agent-sdk","title":"Senior Backend Engineer (m/f/d) - Agent SDK","company":{"id":6593,"name":"voize","domain":"voize.com","url":"https://alion.io/company/voize","size_band":null,"is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":{"grade":"B","score":82,"open_postings":9,"ghost_share":0,"stale_share":0.667,"repost_share":0.111,"time_to_fill_p50_days":42,"computed_at":"2026-10-27T05:46:45Z"}},"role":"Backend","role_family":"Backend","seniority":"senior","employment_type":"full_time","work_mode":"remote","remote_scope":"stated_countries","remote_scope_basis":"board_field","remote_working_hours":null,"hiring_geo_confidence":"inferred","locations":["Berlin, Germany","Dortmund, Germany","Göttingen, Germany","Hanover, Germany","Munich, Germany","Cologne, Germany","Hamburg, Germany"],"countries":["DE"],"hiring_countries":["DE"],"hiring_countries_total":1,"salary":null,"salary_estimate":{"min_usd":71000,"max_usd":152000,"period":"year","method":"role_seniority_country_remote_cell","sample_n":24},"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":true,"technologies":[{"name":"AI Agents","optional":false},{"name":"Java","optional":false},{"name":"Kotlin","optional":false},{"name":"LLM Evaluation","optional":false},{"name":"OpenAI Agents SDK","optional":false},{"name":"Scala","optional":false}],"status":"closed","first_seen_at":"2026-09-07T11:00:11Z","employer_posted_date":"2026-09-07","last_verified_at":"2026-10-26T14:49:20Z","board_verified":false,"closed_at":"2026-10-26T14:49:20Z","days_open":49,"trust":{"level":"not_scored","repost_count":null,"flags":[],"days_open":49},"description":"Why voize? Because we're more than just a job!\nAt voize, we believe the greatest gift to frontline workers is time - time to care, connect, and be present. Today, that time is lost to busywork and complex systems that pull them away from what matters most: people.\nOur vision is to change that by building AI companions that seamlessly take over digital workflows. We don't replace humans with technology - we amplify their impact.\nOur mission is backed with a $50M Series A funding led by Balderton Capital, with support from HV Capital, Y Combinator and other leading VCs. Today, 2,000+ facilities trust voize, and over 200,000 users rely on our AI companion to ease their daily workload.\nAs a dynamic team, we combine first-in-class technology with meaningful social impact. And now, we're looking for you to join us on this mission!\nYour Mission: Build the layer every agent moves onto\nAs Senior Backend Engineer on the team behind our Agent SDK, you build and maintain the Kotlin foundation that our AI agents move onto. Agents have grown into a product surface across verticals and markets, and the layer underneath them needs a permanent owner. Your work makes the cost of the second and third agents visibly less than the first, so feature teams can ship at their own pace.\nYour Daily Business - No two days are alike\nBuild and maintain the SDK as an internal product. You shape the runtime and the client-facing contracts that consuming teams build on. The SDK has a roadmap of its own, and you help set it.\n\nYou build the identity layer that agents run on, so customer-facing agents can write with a real user identity. Your responsibilities may include designing and shipping the auth plumbing, depending on what we have already built by your start date.\n\nMake every agent observable from the day it launches. You wire telemetry and error reporting into the SDK by default, and you integrate inference and anonymization so the SDK enforces them for every consumer.\n\nBuild the test kit that the SDK still needs. You create it along with the architecture tests that protect the runtime internals, and you build the path that runs every SDK agent against our ML team's evaluation harness before a model change ships.\n\nAbsorb ecosystem change on behalf of consuming teams. You own Koog version bumps and format compatibility, and you set the shared limits on tool output and token usage, so an upgrade lands once in the SDK and reaches everyone from there.\n\nYour Skillset - What you bring to the table\nSeveral years of production backend experience on the JVM - Kotlin, Java, Scala or similar. Our stack is Kotlin, and you are ready to work in it.\n\nYou have designed APIs that other engineers build against. An SDK or an internal platform where the contract is the product.\n\nYou have built and maintained integrations, and kept them stable when the system on the other side changed.\n\nTesting and observability are part of how you build.\n\nYou are drawn to AI agent systems, and to the orchestration and evaluation work underneath them.\n\nGrowing together - what you can expect at voize\nWe are a fast-growing startup, that means you will take on real problems, grow quickly, and make a real impact, giving frontline workers more time for people\n\nWe foster an open, collaborative culture with regular team events, whether you work from our Berlin office or remotely across Germany\n\nBecome a co-creator of our success with stock options\n\nGenerous perks: 30 vacation days plus your birthday off, Germany Transport Ticket, Urban Sports Club, regular company off-sites, and access to learning platforms such as Blinkist and Audible, plus free language courses\n\nYou decide when you work best, that means flexible working hours and a good hybrid set-up.\n\nReady to talk? Apply now!\nWe look forward to your application and can't wait to meet you - no matter who you are or what background you have!","description_format":"text","description_chars":3893,"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":["Flexible schedule","Stock options"],"hiring_locations":[{"name":"Germany","iso":"DE","kind":"country"},{"name":"Berlin","iso":null,"kind":"city"},{"name":"Munich","iso":null,"kind":"city"},{"name":"Hamburg","iso":null,"kind":"city"},{"name":"Cologne","iso":null,"kind":"city"},{"name":"Hanover","iso":null,"kind":"city"},{"name":"Dortmund","iso":null,"kind":"city"},{"name":"Göttingen","iso":null,"kind":"city"}],"hiring_excludes":[],"relocation_offered":false,"industries":["Speech & Audio AI","Medical AI","EHR & Clinical Software"],"lifecycle":[{"event":"open","at":"2026-09-07T11:15:30Z"},{"event":"close","at":"2026-10-26T14:49:20Z"}],"visa":[],"liveness":null,"pay":null,"html_url":"https://alion.io/job/voize-senior-backend-engineer-kotlin-mfd-agent-sdk","json_url":"https://alion.io/job/voize-senior-backend-engineer-kotlin-mfd-agent-sdk.json","meta":{"generated_at":"2026-10-27T15:38:43Z","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":4552,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-28T00:00:00Z"}},"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":6593},"rest":"https://alion.io/mcp/rest/get_company?id=6593"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fvoize-senior-backend-engineer-kotlin-mfd-agent-sdk"},{"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%2Fvoize-senior-backend-engineer-kotlin-mfd-agent-sdk"},{"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%2Fvoize-senior-backend-engineer-kotlin-mfd-agent-sdk"},{"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/voize-senior-backend-engineer-kotlin-mfd-agent-sdk\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fvoize-senior-backend-engineer-kotlin-mfd-agent-sdk"}]}