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I'm a Senior Full Stack Developer with 8+ years of experience designing and building scalable applications across Billing, Fintech, and iGaming. I own system design and full-stack delivery—from modern Angular frontends to robust Node.js backends—and have led architecture modernization initiatives, including monorepo migrations and cloud-native deployments on AWS. I enjoy collaborating with product teams to translate complex requirements into secure, high-performance, real-time applications. I mentor engineers, advocate for UX-focused design, and strive to deliver measurable business impact while keeping code clean and maintainable.…I'm a Senior Full Stack Developer with 8+ years of experience designing and building scalable applications across Billing, Fintech, and iGaming. I own system design and full-stack delivery—from modern Angular frontends to robust Node.js backends—and have led architecture modernization initiatives, including monorepo migrations and cloud-native deployments on AWS. I enjoy collaborating with product teams to translate complex requirements into secure, high-performance, real-time applications. I mentor engineers, advocate for UX-focused design, and strive to deliver measurable business impact while keeping code clean and maintainable.

Roman Saito

Front-End Developer, Full Stack Developer, Back-End Developer, +2

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I'm a Senior Full Stack Developer with 8+ years of experience designing and building scalable applications across Billing, Fintech, and iGaming. I own system design and full-stack delivery—from modern Angular frontends to robust Node.js backends—and have led architecture modernization initiatives, including monorepo migrations and cloud-native deployments on AWS. I enjoy collaborating with product teams to translate complex requirements into secure, high-performance, real-time applications. I mentor engineers, advocate for UX-focused design, and strive to deliver measurable business impact while keeping code clean and maintainable.…I'm a Senior Full Stack Developer with 8+ years of experience designing and building scalable applications across Billing, Fintech, and iGaming. I own system design and full-stack delivery—from modern Angular frontends to robust Node.js backends—and have led architecture modernization initiatives, including monorepo migrations and cloud-native deployments on AWS. I enjoy collaborating with product teams to translate complex requirements into secure, high-performance, real-time applications. I mentor engineers, advocate for UX-focused design, and strive to deliver measurable business impact while keeping code clean and maintainable.

Available to hire

I’m a Senior Full Stack Developer with 8+ years of experience designing and building scalable applications across Billing, Fintech, and iGaming. I own system design and full-stack delivery—from modern Angular frontends to robust Node.js backends—and have led architecture modernization initiatives, including monorepo migrations and cloud-native deployments on AWS.

I enjoy collaborating with product teams to translate complex requirements into secure, high-performance, real-time applications. I mentor engineers, advocate for UX-focused design, and strive to deliver measurable business impact while keeping code clean and maintainable.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

English

Fluent

Work Experience

Senior Software Engineer at IoT Billing International Pte Ltd

February 1, 2023 - Present

Directed Angular migrations (v9–v20) and Ionic migrations (v3–v8), introduced Nx monorepo architecture enabling multiple squads to collaborate on shared modules and libraries while improving app performance by 40%. Partnered with PM to integrate human-factor design principles, boosting customer satisfaction scores by 25%. Established CI/CD pipelines with GitLab CI and Docker; deployed production workloads on AWS (EC2, S3, CloudFront) and halved deployment times. Set up automated testing and static analysis tools, enforcing coding standards and reducing bug density by 35%. Mentored squads on Angular best practices and emerging trends (standalone APIs, signals) and established cross-team coding conventions. Optimized NodeJS-based backend integrations, streamlining API consumption and reducing latency.

Senior Front-End Engineer at Right Stakes

January 1, 2021 - January 1, 2023

Spearheaded UI overhaul for Aposta 1 (Angular 12), achieving 50% faster load times and 30% higher engagement. Designed and shipped interactive gaming features including a Magic-Wheel game inspired by Blaze Double, ensuring smooth scalability under peak loads. Prototyped multiple UI iterations to guide stakeholders toward data-driven design choices. Led and mentored a 12-person dev team on Angular, TypeScript, NgRx, RxJS, WebRTC; implemented automated E2E testing with Cypress, improving delivery velocity. Implemented CI/CD workflows with Jenkins and Docker; deployed to Azure Kubernetes Service and reduced manual QA.

Senior Full-Stack Developer at GIANTY

January 1, 2016 - January 1, 2021

Enhanced and modernized Java (Spring Boot) and C# (.NET Core) REST APIs with stronger error handling, monitoring, and test coverage. Architected scalable front-end systems leveraging multi-threading, mutexes, and semaphores, following TDD principles. Secured apps via OpenID Connect and OAuth 2.0 across microservices. Containerized apps with Docker and orchestrated deployments via Kubernetes. Built CI/CD pipelines using Jenkins and GitLab CI; migrated legacy monoliths to microservices on AWS. Contributed to NodeJS services handling real-time data processing pipelines, ensuring efficient cross-platform integration.

Senior Software Engineer (Angular/ Ionic, AWS) at IoT Billing International Pte Ltd

February 1, 2023 - Present

Revamped Angular v9–v20 and Ionic v3–v8 via an Nx monorepo, delivering 20% faster initial loads and API responses. Redesigned critical billing workflows with UX usability testing, increasing customer satisfaction by 25%. Implemented real-time KPI dashboards with ngx-charts for data-driven decisions. Managed front-end delivery on AWS (ECS, S3, CloudFront), increasing cache efficiency and reliability. Built GitLab CI and Docker pipelines, reducing deployment time by 50% and streamlining QA. Mentored engineers on Angular signals, standalone APIs, and RxJS. Embedded biometric authentication in Ionic flows and added automated tests with static analysis to reduce errors.

Senior Front-End Engineer (Angular, Nx Monorepo) at Cartwheel - Startup

February 1, 2024 - September 1, 2024

Shipped contractor invoicing and compliance features; built full-stack components including auth, forms, and dashboards. Engineered a multi-app Nx monorepo, standardizing linting/testing and increasing cross-app code reuse. Published a private Angular component library with 30+ components, reducing rework by 20% and speeding feature delivery by 15%. Upgraded Angular from v12 to v17, enabling standalone APIs, esbuild, and SSR. Created a modern dashboard UI with ApexCharts for FinTech clients.

Senior Software Engineer (Angular/ Ionic) at Right Stakes

January 1, 2021 - January 1, 2023

Led a full UI overhaul for Aposta1 (Angular 12), improving load times by 50% and user engagement by 30%. Shipped interactive game experiences with performance-focused UI architecture and reusable components. Created a shared Angular library with 20+ components for two apps, increasing UI reuse by 30% and speeding delivery by 15%. Enabled a team of 12 with Angular/TypeScript, NgRx/RxJS, WebRTC, SignalR, and E2E testing.

Software Engineer (Full Stack / Cloud) at GIANTY

January 1, 2016 - January 1, 2021

Fortified REST APIs with robust error handling and 30+ unit/integration tests. Built scalable multithreaded systems with mutexes/semaphores and TDD. Secured apps via OpenID Connect and OAuth 2.0 for identity management across microservices. Automated Dockerized Kubernetes rollouts, reducing deployment failures and improving reliability. Built CI/CD pipelines with Jenkins and GitLab CI across AWS (EKS, RDS, S3). Migrated legacy monoliths to AWS microservices, lowering infra costs and increasing uptime. Contributed to NodeJS services handling real-time data processing pipelines.