{"id":841092,"url":"https://alion.io/job/kustom-senior-backend-engineer","title":"Senior Backend Engineer","company":{"id":693583,"name":"Kustom","domain":"kustom.co","url":"https://alion.io/company/kustom-2","size_band":"51-200","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Teamtailor","truth_index":null},"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":["Stockholm, Sweden"],"countries":["SE"],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":null,"experience_years_min":7,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Agile","optional":false},{"name":"AWS","optional":false},{"name":"Git","optional":false},{"name":"GitHub","optional":false},{"name":"Java","optional":false},{"name":"Spring Boot","optional":false},{"name":"Spring Framework","optional":false}],"status":"live","first_seen_at":"2024-10-23T12:02:58Z","employer_posted_date":"2024-10-23","last_verified_at":"2026-11-03T12:59:17Z","board_verified":true,"closed_at":null,"days_open":741,"trust":{"level":"stale","repost_count":0,"flags":["stale"],"days_open":740},"description":"Be a part of the next big thing\nDo you thrive on tackling complex challenges? Are you passionate about creating impactful solutions that drive commerce forward? Are you someone who believes in encouraging and elevating those around you? \nAbout us\nKustom, formerly known as Klarna Checkout (KCO), is the Nordic market leader in digital checkout solutions. Today, we support over 24,000 merchants across more than 170 countries, providing a streamlined checkout experience. We offer localized solutions in 18 markets, tailored to specific languages, currencies, and payment methods. No matter where your business operates, we deliver a checkout experience that meets the needs of both merchants and shoppers - driving growth globally.\nThe role\nWe are looking to hire a Backend Engineer to join our development team. In this role, you will be responsible for designing and implementing robust server-side solutions using modern technologies and frameworks. You will work closely with product managers and fellow engineers to deliver high-performance, scalable applications that power our core business infrastructure.\nAs an integral part of our development team, you'll play a crucial role in developing and maintaining our essential backend infrastructure. We need a detailed oriented person who can design and implement efficient, future-proof solutions for complex business problems. Your knowledge and vision will be instrumental in building a solid technical foundation that ensures our product remains reliable and performant as we grow.\nHere at Kustom, you'll get to drive innovation, and leave your mark on our technical architecture. As part of our cross-functional Agile team, you'll collaborate with talented peers to create digital products that revolutionize how merchants worldwide conduct their business.\nOur engineering teams are based in Stockholm, where we prioritize in-person collaboration at our office to foster strong team dynamics.\nThings you'll be doing\nImplement scalable, high-performance backend services that power our global payment infrastructure\n\nLead technical discussions and mentor junior team members while contributing to architectural decisions\n\nDrive engineering excellence through code reviews, best practices, and technical documentation\n\nWork closely with Product and Design to implement robust technical solutions\n\nContribute to our technical roadmap and help shape the future of our platform\n\nSkills and experience you'll need\nBachelor’s degree in Computer Science, Engineering, or a related field.\n\n7+ years of professional experience in Backend development, with deep expertise in Java\n\nStrong track record of designing and implementing large-scale distributed systems\n\nAdvanced knowledge of Spring Framework and Spring Boot\n\nExtensive experience with AWS cloud services and microservices architecture\n\nExpert-level understanding of database design, optimization, and various storage solutions\n\nProven experience with Git and Github for version control and team collaboration\n\nDeep understanding of RESTful APIs, API security, and performance optimization\n\nWe believe you'll thrive in this role if you have\nStrong technical leadership skills with a track record of mentoring junior engineers\n\nPassion for solving complex engineering challenges and driving technical innovation\n\nExperience with high-throughput, low-latency systems is a plus\n\nExcellent communication skills and ability to explain complex technical concepts clearly\n\nTrack record of driving technical initiatives and improving system architecture\n\nStrong commitment to code quality, testing, and technical documentation\n\nAbility to balance technical excellence with practical business needs\n\nBenefits \nSecure your future with a competitive pension package, including both national and occupational pension contributions.\n\nComprehensive health coverage with extensive health insurance, long-term illness protection, and flexible salary exchange options.\n\nInvest in your wellbeing with an annual wellness allowance of 3,000 SEK to spend on the activities that keep you healthy and energized.\n\nMore time to enjoy life with an extra day off when major holidays, such as Christmas Eve or New Year’s Eve, fall on a weekend.\n\nA place to grow\nAt Kustom, you’re not going to be just another face in the crowd. This is a place where we elevate each other and celebrate success as a team. We believe in our ability to create excellence - and have fun doing it!\nAnd we know we set high expectations, but we also know that the road to success isn’t a straight line. We support and encourage each other to try, to fail, to try again. Because that’s how we grow, individually and together.\nDoes this sound like the place for you?\nAbout your application\nPlease apply in English. At Kustom we welcome everyone! We don’t care where you’re from, whom you love, what kind of food is your favorite (well, unless we’re having a celebration together, then we’ll have to know!), if you believe in this or in that - everyone is welcome!\n\nGiving the above, we treat all candidates the same! That’s why we have this awesome recruitment tool to keep track of all the amazing talents that apply - so please; apply through the system and we’ll make sure to keep you updated along the recruitment process. And be noticed that we can’t keep track of all CV’s and likewise via email.\n\nWe value your privacy! When you apply, we'll handle your data with care. Want to know more about how we use your information? Check out our FAQs at the bottom of the jobs page - we've got all the details there for you!","description_format":"text","description_chars":5578,"description_truncated":false,"requirements":{"experience_years_min":7,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"bachelor","optional":false},"security_clearance":false,"languages":[]},"benefits":["Health insurance"],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["E-commerce Platforms","Payment Processing & Gateways"],"lifecycle":[{"event":"open","at":"2026-09-12T21:47:06Z"},{"event":"open","at":"2026-09-30T01:20:00Z"},{"event":"open","at":"2026-10-12T05:37:38Z"}],"visa":[],"liveness":{"score":8,"band":"cold","label":"Long shot","p_open":1,"p_active":0.275,"p_room":0.28,"age_days":740,"expected_fill_days":36,"reasons":["conf:3","win:tail","crowd:"],"computed_at":"2026-11-03T05:54:40Z"},"pay":null,"html_url":"https://alion.io/job/kustom-senior-backend-engineer","json_url":"https://alion.io/job/kustom-senior-backend-engineer.json","meta":{"generated_at":"2026-11-03T17:41:30Z","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":24707,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-11-04T00:00:00Z"}},"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":693583},"rest":"https://alion.io/mcp/rest/get_company?id=693583"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fkustom-senior-backend-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%2Fkustom-senior-backend-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%2Fkustom-senior-backend-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/kustom-senior-backend-engineer\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fkustom-senior-backend-engineer"}],"agent":{"mcp":"https://alion.io/mcp/jobs","mcp_open":"https://alion.io/mcp/open","next":[{"tool":"get_job","arguments":{"id":841092}},{"tool":"search_jobs","arguments":{"company":"kustom.co","detail":"compact"}},{"tool":"match_people","arguments":{"job_id":841092},"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. 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