Sameera Sineen

· Designed customer self-service portals using React.js, TypeScript, Node.js, and Python microservices on AWS (ECS, Lambda, S3), serving 5M+ cardholders and improving usability scores by 30% across desktop and mobile.

· Delivered accessibility-first dashboards with WCAG 2.1 compliance and ARIA roles, embedding automated Lighthouse checks in pipelines, which reduced audit defects by 25% and passed two consecutive banking compliance reviews.

· Adopted a Micro Front End framework to decouple payments, rewards, and fraud modules; coordinated through Git branching and Jira epics, this reduced cross-team release dependencies by 20% and improved delivery predictability.

· Built GraphQL and RESTful APIs in Spring Boot and Node.js to connect with VisaNet and third-party gateways, raising checkout success rates by 15% and supporting real-time transaction authorization flows during peak loads.

· Optimized backend data flows with PostgreSQL, MongoDB, and Kafka event streams, reducing processing latency by 28% and improving fraud anomaly detection accuracy across AML pipelines.

· Automated CI/CD pipelines with Jenkins, GitHub Actions, and Docker, deploying to AWS Kubernetes clusters; release cycles dropped from 3 hours to under 20 minutes while supporting zero-downtime rollouts.

· Engineered fraud detection dashboards with D3.js and React Charts, enabling compliance officers to detect suspicious activity 40% faster and lower false positives by 20%.

· Hardened settlement workflows with OAuth2/JWT and PCI DSS role-based access, enabling successful global security audits and strengthening cardholder data protection.

· Integrated Prometheus/Grafana monitoring with custom Python alert scripts, cutting mean-time-to-detection of transaction failures by 45% and providing real-time visibility for operations teams.

· Built a real-time transaction monitoring service on AWS Kinesis and DynamoDB, scaling to process 50K+ events per second during Black Friday peaks, which improved fraud response times by 32%.

· Deployed AWS Secrets Manager and IAM policies across payment APIs to eliminate hardcoded credentials, reducing security vulnerabilities and ensuring PCI DSS compliance across 12 global regions.

· Mentored junior engineers through structured code reviews and secure coding workshops, raising overall team delivery quality and cutting production issues by 40%.

· Delivered multi-tenant banking and retail dashboards using Vue.js, Angular, and TypeScript, enabling reuse across multiple clients and cutting delivery timelines by 35%.

· Translated wireframes into branded UI components with semantic HTML and ARIA roles, which improved accessibility compliance scores and reduced client-side audit issues by 20%.

· Developed Spring Boot APIs to support financial reporting features, ensuring real-time accuracy and improving reconciliation performance by 15%.

· Introduced Micro Front End structures across retail suites, allowing regional teams to ship localized features independently and reducing dependency bottlenecks by 20%.

· Built shared UI libraries with Vuex state handling and Git-based workflows, improving consistency across teams and reducing code duplication by 25%.

· Integrated Kafka-driven event messaging for retail order tracking and inventory updates, enabling near real-time dashboards and reducing manual reconciliation workload.

· Tuned Webpack build pipelines and bundle size optimizations, which cut global page load times by 28% and boosted SEO visibility scores.

· Rebuilt enterprise UIs with Bootstrap and custom theming, aligning applications with strict financial brand guidelines and raising usability ratings by 18%.

· Implemented secure API token handling and SSO with Azure Active Directory, reducing authentication errors during compliance audits by 22%.

· Established CI/CD pipelines with Azure DevOps and GitHub Actions, improving release predictability and cutting rollback incidents by 30%.

· Partnered with QA teams to design automated test suites in Selenium and Jasmine, which doubled regression coverage and reduced post-release defects by 30%.

· Assisted in data migration from on-prem SQL Server to Azure SQL and Cosmos DB, reducing infrastructure costs and improving dashboard query speeds by 25%.

· Contributed to healthcare claim-tracking systems by coding UI modules in JavaScript (ES6), HTML5, and CSS3, enabling staff to process eligibility checks 25% faster across multiple hospital units.

· Built REST APIs in Spring Boot and Python to integrate Epic EHR systems with third-party insurance platforms, cutting claim processing delays by 30% and improving patient turnaround time.

· Designed and optimized SQL schemas and queries in MySQL/PostgreSQL, which reduced database errors during peak loads and improved medical record retrieval speeds by 40%.

· Collaborated with compliance officers to embed HIPAA audit-trail logging into Epic-linked portals, improving regulatory review scores and ensuring patient data security.

· Assisted in setting up CI/CD pipelines in Jenkins for compliance-driven deployments, gaining early exposure to automation and ensuring predictable release cycles.

· Wrote and executed JUnit and integration tests for Epic workflows, stabilizing patient record modules and reducing audit-driven downtime by 25%.

· Participated in the migration of legacy claim adjudication systems to modular Java/React applications, improving maintainability and cutting downtime during upgrades.

· Coordinated with cross-functional teams to implement secure API authentication between Epic and insurance providers, reducing rejected claims and ensuring compliance.

· Developed Python-based data validation scripts to cross-check insurance claim records before Epic ingestion, lowering data mismatches by 18%.

· Documented healthcare workflows and created knowledge transfer guides for Epic modules, supporting smooth onboarding of new engineers and compliance auditors.