{"id":758825,"url":"https://alion.io/job/sent-backend-engineer-net","title":"Backend Engineer (.NET) – WhatsApp/WABA","company":{"id":687527,"name":"Sent","domain":"sent.dm","url":"https://alion.io/company/sent-2","size_band":"201-500","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Ashby","truth_index":{"grade":"C","score":65,"open_postings":12,"ghost_share":0.583,"stale_share":0,"repost_share":0,"time_to_fill_p50_days":null,"computed_at":"2026-11-04T06:34:25Z"}},"role":"Backend","role_family":"Backend","seniority":"middle","employment_type":"full_time","work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"explicit","locations":["Pristina, Kosovo"],"countries":["XK"],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":null,"experience_years_min":3,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"ASP.NET Core","optional":false},{"name":"C#","optional":false},{"name":"Rest API","optional":false},{"name":"WhatsApp","optional":false}],"status":"live","first_seen_at":"2026-04-24T19:13:37Z","employer_posted_date":"2026-04-24","last_verified_at":"2026-11-04T19:44:16Z","board_verified":true,"closed_at":null,"days_open":194,"trust":{"level":"ghost","repost_count":0,"flags":["stale","company_stale"],"days_open":193},"description":"Job Title: Backend Engineer (.NET) - WhatsApp/WABA\nLocation: Prishtina, Kosovo\nCompany Overview\nSent is building the messaging infrastructure that powers how businesses communicate with their customers. We provide a unified API for SMS, WhatsApp, iMessage, and RCS, making it simple for developers to reach people across multiple messaging channels.\nFollowing our recent Series A funding, we're growing rapidly and building the future of business messaging.\nPosition Summary\nWe are looking for an experienced Backend Engineer (.NET) with hands-on WhatsApp Business Platform (WABA) experience to join our engineering team in Prishtina.\nIn this role, you will build and maintain the core backend services that power Sent's messaging infrastructure, with a particular focus on our WhatsApp integrations. You'll work on APIs, messaging workflows, webhooks, message templates, delivery events, and backend systems that process large volumes of messages every day.\nYou'll work closely with our engineering and product teams to build reliable, scalable messaging systems and strengthen Sent's integration with WhatsApp and other communication channels.\nKey Responsibilities\nDesign, build, and maintain backend services using C#, .NET, and ASP.NET Core.\n\nBuild and maintain integrations with the WhatsApp Business Platform (WABA), WhatsApp Cloud API, and related Meta APIs.\n\nDevelop and maintain WhatsApp messaging workflows, including message sending and receiving, webhooks, templates, delivery statuses, and messaging events.\n\nDesign and maintain RESTful APIs that power Sent's multi-channel messaging platform.\n\nIntegrate Sent's platform with Meta/WhatsApp, carrier networks, third-party messaging providers, and internal services.\n\nBuild reliable systems for processing asynchronous messaging events, retries, failures, and high-volume traffic.\n\nMonitor and improve the reliability, performance, and scalability of backend services.\n\nIdentify bottlenecks, optimize database queries, and evolve database schemas as the platform scales.\n\nTroubleshoot production issues and external API or messaging integration failures.\n\nParticipate in technical design and architecture discussions to improve the security and scalability of Sent's backend systems.\n\nCollaborate closely with Product, Frontend, DevOps, and other Backend Engineers to deliver end-to-end features.\n\nQualifications & Skills\n3+ years of professional experience with C# / .NET / ASP.NET Core building production backend services.\n\nHands-on experience with the WhatsApp Business Platform (WABA), WhatsApp Cloud API, or WhatsApp Business APIs.\n\nExperience working with WhatsApp messaging workflows, including webhooks, message templates, delivery statuses, and messaging events.\n\nStrong experience designing, building, and maintaining RESTful APIs.\n\nStrong understanding of asynchronous systems, webhooks, queues, retries, and event-driven architectures.\n\nSolid knowledge of relational databases, including schema design, efficient queries, and data integrity.\n\nStrong understanding of authentication, authorization, API security, and secure backend development.\n\nExperience troubleshooting production integrations and third-party API failures.\n\nStrong security and reliability mindset.\n\nStrong written and verbal English communication skills.\n\nAbility to work effectively with engineering, product, and other cross-functional teams.\n\nExperience with WhatsApp Business Solution Providers (BSPs), Meta Business Manager, phone number onboarding, or WABA configuration is considered a strong advantage.\n\nExperience with CPaaS, telecommunications, SMS, RCS, messaging infrastructure, or high-volume communication platforms is considered a strong advantage.\n\nExperience building high-availability or high-throughput systems is considered a strong advantage.\n\nWhat We Offer\nWork with an experienced engineering team on products used by customers worldwide.\n\nWork on high-scale messaging infrastructure across WhatsApp, SMS, RCS, and other communication channels.\n\nMeaningful ownership of the systems and integrations you build.\n\nCompetitive salary based on experience.\n\nCareer growth opportunities in a fast-growing US technology company.\n\nPrivate health insurance (including 50% family coverage).\n\nMonthly gym membership allowance.\n\nModern office in central Prishtina.\n\nSnacks, coffee, and refreshments in the office.\n\nRegular company and team activities.\n\nIn accordance with Kosovo Labor Law.\n\nOffice Location\nPrishtina, Kosovo.\n\nWork Schedule\nMonday-Friday, standard business hours, 9:00 AM-5:00 PM.\nFridays are remote.","description_format":"text","description_chars":4571,"description_truncated":false,"requirements":{"experience_years_min":3,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":null,"security_clearance":false,"languages":[{"language":"English","level":"Upper-Intermediate (B2)","optional":false}]},"benefits":["Growth opportunities","Gym membership","Health insurance"],"hiring_locations":[{"name":"Kosovo","iso":"XK","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["Unified Communications","Integration & API Management"],"lifecycle":[{"event":"open","at":"2026-09-11T17:56:26Z"}],"visa":[],"liveness":{"score":4,"band":"cold","label":"Long shot","p_open":1,"p_active":0.154,"p_room":0.28,"age_days":193,"expected_fill_days":30,"reasons":["conf:0","stale_co","ghost","win:tail","crowd:"],"computed_at":"2026-11-04T06:34:25Z"},"pay":null,"html_url":"https://alion.io/job/sent-backend-engineer-net","json_url":"https://alion.io/job/sent-backend-engineer-net.json","meta":{"generated_at":"2026-11-04T21:23:44Z","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":33139,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-11-05T00:00:00Z"}},"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":687527},"rest":"https://alion.io/mcp/rest/get_company?id=687527"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fsent-backend-engineer-net"},{"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%2Fsent-backend-engineer-net"},{"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%2Fsent-backend-engineer-net"},{"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/sent-backend-engineer-net\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fsent-backend-engineer-net"}],"agent":{"mcp":"https://alion.io/mcp/jobs","mcp_open":"https://alion.io/mcp/open","next":[{"tool":"get_job","arguments":{"id":758825}},{"tool":"search_jobs","arguments":{"company":"sent.dm","detail":"compact"}},{"tool":"match_people","arguments":{"job_id":758825},"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. Docs: https://alion.io/developers"}}