Senior Backend Engineer (.NET / Azure)

About the OpportunityOur client is an innovative technology company building software platforms that support large-scale infrastructure and data-driven operations in Japan. As the organization continues to grow, they are looking for an experienced Backend Engineer to help design, build, and scale mission-critical cloud applications.This is an excellent opportunity to join a highly collaborative engineering team where you will have significant influence over architecture, technical decisions, and product evolution while working in an English-speaking environment.ResponsibilitiesDesign, develop, and maintain backend services using C# and ASP.NET CoreDesign and implement scalable REST APIsBuild and optimize database models and application architecturesImprove system performance, reliability, scalability, and maintainabilityDevelop and operate cloud-native solutions on Microsoft AzureParticipate in architecture discussions and technical decision-makingCollaborate with engineers through code reviews and best practicesImprove CI/CD pipelines, development workflows, and engineering productivityContribute to system monitoring, deployment automation, and operational excellenceRequired QualificationsCommercial experience developing web applications with C# and ASP.NET CoreStrong experience designing and implementing REST APIsExperience working with relational databases such as SQL ServerExperience using Entity Framework Core or similar ORM frameworksSolid understanding of object-oriented design principlesExperience developing applications in cloud environmentsExperience writing automated testsAgile software development experienceStrong English communication skillsPreferred QualificationsMicrosoft Azure infrastructure experienceAzure DevOps experienceKnowledge of DDD, Clean Architecture, and CQRSExperience with React or modern frontend frameworksAbility to independently research and learn technical topics in EnglishTechnology StackBackendC#ASP.NET CoreEntity Framework CoreMediatRFastEndpointsxUnitFrontendTypeScriptReactCloudMicrosoft AzureAzure SQL DatabaseWhat We OfferCompetitive annual compensation: JPY 6M - 12MFlexible working hours with no core timeHybrid / remote-friendly work environmentOpportunity to influence architecture and technical strategyInternational and English-speaking engineering cultureAccess to leading AI development toolsFast career progression opportunities as the organization growsWork on products with tangible real-world impact