Senior Java & .NET Developer
Senior Java & .NET DeveloperLocation: 100% RemoteExperience: 6+ YearsType: ContractJob SummaryThe County of Orange is seeking a Senior Java & .NET Developer with strong enterprise application development experience. Candidates with expertise in both Java and .NET are preferred. Candidates with strong expertise in one stack and working knowledge of the other may also be considered.The workload is approximately 70% .NET and 30% Java, so strong .NET experience is preferred.The ideal candidate will have hands-on experience with software architecture, application modernization, secure application development, REST APIs, payment-processing applications, and vulnerability remediation.Required Skills6+ years of enterprise software development experienceStrong knowledge of object-oriented programming, design principles, and design patternsStrong .NET experience with C#, .NET 8/10+, ASP.NET Core, Web API, and MVCJava enterprise development experience with Java 11/17+, Spring, Spring Boot, and REST APIsFull-stack web application architecture and client/server developmentStrong SQL and relational database experience with SQL Server and/or OracleExperience designing and developing secure REST APIs and web servicesExperience with authentication, authorization, encryption, input validation, secure logging, and vulnerability remediationStrong knowledge of OWASP Top 10 and secure coding practicesExperience with cloud application deployment and modernization, preferably Microsoft AzureExperience with Git, Azure DevOps, CI/CD, and DevSecOpsExperience with AI-assisted development tools such as GitHub Copilot, OpenAI Codex, or Claude CodeStrong understanding of SDLC, Agile, and software testingSecurity & ComplianceApplication security and secure coding experienceOWASP Top 10 / OWASP ASVSPCI DSS knowledgeNIST Cybersecurity Framework familiarityExperience identifying and resolving application security vulnerabilitiesExperience securing public-facing, high-traffic applicationsExperience handling sensitive financial dataPreferred ExperiencePayment gateway or payment processing integrationsSoftware design and architectureApplication modernizationFinancial/payment applicationsOAuth2, OpenID Connect, and Microsoft Entra IDSonarQube, Checkmarx, Fortify, or similar security toolsTechnical documentation and architecture/implementation plansStrong written and verbal communication skillsAbility to work independently and collaborativelyPreferred Technical StackBackend: Java 11/17+, Spring Boot, C#, .NET 8/10+, ASP.NET Core, Web API, MVCFrontend: HTML5, JavaScript, CSSAPIs/Security: REST, OAuth2, OpenID Connect, Microsoft Entra ID, OWASPDatabase: SQL Server, OracleCloud: Microsoft AzureDevOps: Git, Azure DevOps, CI/CD, DevSecOpsSecurity Tools: SonarQube, Checkmarx, FortifyAI Tools: GitHub Copilot, OpenAI Codex, Claude CodeResponsibilitiesDesign, develop, and maintain enterprise-grade Java and .NET applicationsBuild secure REST APIs and web servicesModernize existing applications and improve application architectureIdentify, investigate, and remediate security vulnerabilitiesImplement authentication, authorization, encryption, validation, and secure loggingDevelop and integrate payment-processing solutionsOptimize SQL queries and relational database performanceSupport Azure cloud deployment and modernization initiativesImplement CI/CD and DevSecOps practicesProduce technical documentation and implementation plansCollaborate with developers, architects, security teams, and other stakeholdersMaintain high-quality, secure, and scalable code