{"id":2162467,"url":"https://alion.io/job/madiff-senior-principal-java-developer","title":"Senior Principal Java Developer","company":{"id":4374669,"name":"Madiff","domain":"madiff.eu","url":"https://alion.io/company/madiff-2","size_band":"51-200","is_staffing_agency":true,"employer_type":"agency","is_intermediary":false,"listed_via":null,"ats_vendor":"Zoho Recruit","truth_index":null},"role":"Backend","role_family":"Backend","seniority":"lead","employment_type":"full_time","work_mode":"hybrid","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["Warsaw, Poland"],"countries":["PL"],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":{"min_usd":65000,"max_usd":106000,"period":"year","method":"role_seniority_country_remote_cell","sample_n":52},"experience_years_min":5,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Agile","optional":false},{"name":"Clean Architecture","optional":false},{"name":"Java","optional":false},{"name":"Oracle","optional":false},{"name":"Rest API","optional":false},{"name":"SQL","optional":false},{"name":"CI/CD","optional":true}],"status":"live","first_seen_at":"2026-10-09T08:26:24Z","employer_posted_date":"2026-10-09","last_verified_at":"2026-10-12T12:16:47Z","board_verified":true,"closed_at":null,"days_open":3,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":3},"description":"We are looking for a Senior Principal Java Backend Developer to join a mission-critical backend platform operating at enterprise scale. The role is focused on hands-on backend development within a high-volume, production-critical fintech environment, with additional responsibility for mentoring engineers and supporting technical alignment across the team. The work involves building and maintaining core services supporting transaction processing, financial reporting, and merchant-facing functionality under strict security, availability, and performance requirements.\nResponsibilities\n\nDesign, develop, and maintain backend services using Java 17+\nBuild scalable microservices supporting high transaction volumesand real-time processing\n\nIntegrate backend services with Oracle databases, internalfinancial systems, and external APIs\n\nEnsure security, performance, and reliability aligned with fintechstandards\n\nCollaborate closely with product managers, architects, and analysts\nContribute to architectural decisions and platform modernisation\nSupport production deployments, monitoring, and troubleshooting\nMentor junior engineers and raise engineering standards\nParticipate activelyin code reviews and quality initiatives\n\nRequirements\nMinimum 5 years of commercial Java backend experience\nStrong expertise with Java 17+\nHands-on experience with Oracle, SQL, and PL/SQL\nSolid experience with microservices and REST APIs\nStrong understanding of clean architecture and design patterns\nExperience working in Agile delivery teams\nHigh ownership mindsetand strong communication skills\n\nPrevious technicalleadership or Team Lead experience (min 1 year) Nice to have \n\nExperience in fintech, payments, or bankingenvironments\n\nExposure to CI/CD, DevOps, and containerisedenvironments\n\nBenefits\nSolid, competitive salary\nWork in multinational environment on international projects\nComprehensive healthcare\nLong-term B2B contract with stable project pipeline\nHybrid work model","description_format":"text","description_chars":1972,"description_truncated":false,"requirements":{"experience_years_min":5,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":null,"security_clearance":false,"languages":[]},"benefits":["Hybrid work"],"hiring_locations":[{"name":"Poland","iso":"PL","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["Information Technology","Property Development","IT Consulting & Digital Transformation"],"lifecycle":[{"event":"open","at":"2026-10-09T08:26:24Z"}],"visa":[],"liveness":{"score":52,"band":"ok","label":"Likely open","p_open":1,"p_active":0.516,"p_room":1,"age_days":2,"expected_fill_days":30,"reasons":["conf:1","agency","win:early","comp:brand"],"computed_at":"2026-10-12T06:55:09Z"},"pay":null,"html_url":"https://alion.io/job/madiff-senior-principal-java-developer","json_url":"https://alion.io/job/madiff-senior-principal-java-developer.json","meta":{"generated_at":"2026-10-12T13:10:17Z","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":20599,"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":4374669},"rest":"https://alion.io/mcp/rest/get_company?id=4374669"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fmadiff-senior-principal-java-developer"},{"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%2Fmadiff-senior-principal-java-developer"},{"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%2Fmadiff-senior-principal-java-developer"},{"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/madiff-senior-principal-java-developer\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fmadiff-senior-principal-java-developer"}]}