{"id":3039026,"url":"https://alion.io/job/xflow-senior-backend-engineer-go","title":"Senior Backend Engineer (Go)","company":{"id":4431640,"name":"Xflow","domain":"xflow.com","url":"https://alion.io/company/xflow-com","size_band":null,"is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"BambooHR","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":["Warsaw, Poland"],"countries":["PL"],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":{"min_usd":60000,"max_usd":100000,"period":"year","method":"role_seniority_country_remote_cell","sample_n":348},"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Apache Kafka","optional":false},{"name":"AWS","optional":false},{"name":"CI/CD","optional":false},{"name":"Docker","optional":false},{"name":"Go","optional":false},{"name":"gRPC","optional":false},{"name":"Kubernetes","optional":false},{"name":"MySQL","optional":false},{"name":"NATS","optional":false},{"name":"OpenSearch","optional":false},{"name":"PostgreSQL","optional":false},{"name":"Redis","optional":false},{"name":"Rest API","optional":false},{"name":"Blue-Green Deployment","optional":true},{"name":"GitLab CI","optional":true},{"name":"Grafana","optional":true},{"name":"Helm","optional":true},{"name":"JavaScript","optional":true},{"name":"Loki","optional":true},{"name":"OpenTelemetry","optional":true},{"name":"PHP","optional":true},{"name":"Prometheus","optional":true},{"name":"Python","optional":true},{"name":"React.js","optional":true},{"name":"Sentry","optional":true},{"name":"Twelve-Factor App","optional":true},{"name":"TypeScript","optional":true},{"name":"WebSockets","optional":true}],"status":"live","first_seen_at":"2026-09-11T00:00:00Z","employer_posted_date":"2026-09-11","last_verified_at":"2026-10-24T02:26:10Z","board_verified":true,"closed_at":null,"days_open":43,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":43},"description":"X-FLOWis a mobile game development company established in 2018. We gained recognition after the release of Happy Color, the most popular digital coloring book and one of the most successful ad-driven mobile apps in the world.\nWe are currently looking for a Senior Backend Engineer (Go)for our flagship project, Happy Color.\nKey Responsibilities:\nDesign and develop microservices in Go (REST/gRPC), public and internal APIs.\nIntegrate with external services, develop contracts.\nOptimize performance, profiling, reduce latency, and scale systems.\nDesign database schemas, perform migrations, indexing, and query optimization.\nWork with PostgreSQL/MySQL, Redis, Kafka/NATS and event-driven integrations.\nImplement and maintain CI/CD, cloud infrastructure (AWS) with Docker/Kubernetes.\nEnsure quality: writing tests (unit/integration/e2e), code reviews, automation of checks.\nEnsure observability and reliability: logging, metrics, alerting, tracing.\nParticipate in architectural design, RFCs/ADRs.\nRequirements:\n3+ years of commercial development experience, including 3+ years with Golang.\nProficient in Go: context handling, concurrency (goroutines/channels), profiling (pprof), gRPC/REST, generics, modularity.\nStrong understanding of backend architecture, API design, microservices, and distributed systems.\nDatabases: PostgreSQL/MySQL, Redis; design, indexing, transactions.\nQueues/Buses: Kafka/NATS - experience in designing event-driven integrations.\nExperience with search technologies such as OpenSearch would be a plus.\nCI/CD: GitLab CI, feature flags, migrations, blue-green/rolling deployments.\nTesting: Go testing/testify, integration/e2e.\nSecurity: OAuth2, JWT.\nUnderstanding of DDD principles, SOLID, 12-factor methodology, observability (Prometheus/Grafana, OpenTelemetry).\nRussian - C1/higher, English - B1.\nNice to have:\nExperience with Python and/or PHP.\nExperience with TypeScript, JavaScript and React.\nExperience with OpenSearch.\nData architecture: CQRS/Event Sourcing, idempotency, deduplication.\nExperience building BFFs, WebSockets.\nFeature flags, experiments/A-B testing, product metrics.\nTechnology Stack (Primary):\nBackend: Go, gRPC/REST, PostgreSQL, Redis, Kafka.\nDevOps: GitLab CI, Docker, nice to have: Kubernetes, AWS, Helm.\nObservability: Prometheus, Grafana, Loki, OpenTelemetry, Sentry.\nSearch: OpenSearch.\nWhat We Offer:\nCompetitive salary and benefits package.\nOpportunity to work with a talented and passionate team in a creative and dynamic environment.\nFlexible working hours and remote/office work options.\nCareer growth and professional development opportunities.\nA fun and inclusive company culture that celebrates diversity and creativity.\nJoin us and let’s create great content together!\nWhen you apply for this role, we process your personal data in accordance with our Candidate Privacy Notice( https://xflowgames.com/candidate-privacy-notice).","description_format":"text","description_chars":2888,"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":[{"language":"Russian","level":"Advanced (C1)","optional":false},{"language":"English","level":"Intermediate (B1)","optional":false}]},"benefits":["Flexible schedule","Professional development"],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":[],"lifecycle":[{"event":"open","at":"2026-10-21T22:14:01Z"}],"visa":[],"liveness":{"score":29,"band":"fade","label":"Fading","p_open":1,"p_active":0.646,"p_room":0.45,"age_days":42,"expected_fill_days":27,"reasons":["conf:31","win:tail"],"computed_at":"2026-10-23T05:54:15Z"},"pay":null,"html_url":"https://alion.io/job/xflow-senior-backend-engineer-go","json_url":"https://alion.io/job/xflow-senior-backend-engineer-go.json","meta":{"generated_at":"2026-10-24T03:35:51Z","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":5644,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-25T00:00:00Z"}},"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":4431640},"rest":"https://alion.io/mcp/rest/get_company?id=4431640"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fxflow-senior-backend-engineer-go"},{"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%2Fxflow-senior-backend-engineer-go"},{"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%2Fxflow-senior-backend-engineer-go"},{"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/xflow-senior-backend-engineer-go\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fxflow-senior-backend-engineer-go"}]}