Available to hire
Hi, I’m Rei Taro, a Senior QA Engineer with 10+ years of experience delivering high-quality software for financial platforms and AI/ML pipelines. I’m passionate about building scalable QA strategies, automating robust test infrastructures, and shaping reliable backend systems. I thrive in cross-functional environments and enjoy turning complex requirements into practical, measurable quality improvements.
I love onboarding teams to foster a culture of quality, collaborating across disciplines to improve performance, security, and user experience, and delivering clear, actionable feedback that drives continuous improvement.
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Language
English
Fluent
Japanese
Advanced
Work Experience
Senior Software Engineer at Leobit
August 1, 2022 - November 1, 2025Engineered backend services in Python using FastAPI to streamline document automation, user onboarding, and reporting workflows. Developed event-driven solutions with Celery and Redis for asynchronous processing of financial transaction requests. Deployed microservices on Azure App Services and used Terraform for infrastructure as code. Created and maintained data pipelines for regulatory data exchange with Apache Airflow and Azure Functions. Led security assessments and integrated OAuth2 and Azure AD B2C for secure authentication. Collaborated with cross-functional teams to address integration challenges, ensure compliance, and oversee release strategies.
Senior Software Engineer at Innovature
June 1, 2022 - June 1, 2022Developed backend systems in Python and FastAPI to automate document workflows, streamline user onboarding, and handle complex reporting processes. Created event-driven microservices using Celery and Redis for asynchronous processing of financial data and transaction requests. Managed the deployment of microservices on Azure App Services, leveraging Terraform for infrastructure automation. Engineered data pipelines for secure exchange of regulatory data with Apache Airflow and Azure Functions. Performed security audits and integrated OAuth2 and Azure AD B2C to manage authentication and access controls. Collaborated with cross-functional teams to ensure smooth system integration and regulatory compliance.
Software Developer at Wizcorp
November 1, 2018 - November 1, 2018Developed backend services for trade execution, portfolio management, and account tracking using Python, Flask, and PostgreSQL. Engineered real-time price feed processors with asyncio, WebSockets, and Redis to deliver up-to-the-minute trading data for high-frequency transactions. Collaborated with frontend teams to deliver data through REST APIs and WebSocket channels. Ensured regulatory compliance (MiFID II, GDPR) and internal data security. Implemented comprehensive test suites with PyTest, tox, and mock servers; introduced Celery-based job queuing and scheduling.
Full-Stack Developer at Leobit
August 1, 2022 - November 5, 2025Design and implementation of robust backend services for document automation and reporting workflows. Established Oracle integration for efficient data retrieval/storage, improved system performance, and maintained code quality with Git, JIRA, and Confluence. Implemented unit testing with JUnit achieving high coverage; led automated testing strategies with QF-Test, reducing manual testing and accelerating verification. Collaborated with cross-functional teams to navigate integration challenges and align release strategies with 3-6 week sprints. Used Eclipse for development and optimized CI practices.
Full Stack Developer at Leobit
August 1, 2022 - November 5, 2025Utilized Python to engineer robust backend services through FastAPI, enhancing document automation, user onboarding, and reporting workflows. Managed full stack development with a focus on event-driven solutions utilizing Celery and Redis for asynchronous processing of financial transactions. Implemented infrastructure as code using Terraform to deploy microservices on Azure App Services, achieving seamless operations in the cloud environment. Designed and maintained data pipelines utilizing Apache Airflow and Azure Functions for regulatory data exchanges, ensuring accuracy and timeliness in data flow and processing involving thousands of transactions. Conducted comprehensive security assessments and integrated OAuth2 and Azure AD B2C for scalable authentication solutions, ensuring compliance with industry standards. Fostered collaboration among cross-functional teams to tackle integration challenges and streamline release strategies, successfully managing up to 5 releases per month.
AI Architect at Leobit
August 1, 2022 - November 5, 2025Developed and deployed AI-driven solutions utilizing Azure, Azure AI, and LangChain to enhance document processing and reporting workflows for stakeholders. Engineered backend services in Python with FastAPI for user onboarding and regulatory compliance. Implemented CI/CD pipelines using GitHub Actions, reducing delivery cycle time by ~40%. Managed resources on Azure App Services and used Terraform and Bicep for infrastructure management, reducing provisioning time by ~30%. Architected microservices with Docker and AKS for scalable deployment, achieving uptime over 99.9%. Built event-driven architectures with Celery and Redis, and designed data pipelines with Apache Airflow and Azure Functions to ensure regulatory data exchanges. Conducted security assessments and integrated OAuth2 and Azure AD B2C for robust authentication. Collaborated with cross-functional teams, emphasizing clear English communication and effective integration with stakeholders.
Senior Software Engineer at Innovature
June 30, 2022 - June 30, 2022Designed and implemented AI solutions using Azure AI, LLMs, and LangChain to enhance data processing capabilities and user interactions. Developed robust Python microservices with FastAPI for real-time data processing and scalable document workflows. Automated infrastructure with Terraform, achieving a 70% reduction in deployment time across 3 projects. Created event-driven architectures with Celery and Redis for asynchronous processing and built secure data pipelines with Apache Airflow and Azure Functions. Conducted security audits and implemented OAuth2 and Azure AD B2C for enhanced authentication. Collaborated on CI/CD workflows with GitHub Actions across 5 major releases and leveraged Docker and AKS for optimized performance and resource usage.
Software Developer at Wizcorp
November 30, 2018 - November 30, 2018Developed scalable backend services using Python to support trading operations, leveraging Azure AI for ML models to enable real-time insights. Collaborated with data science teams to integrate MLOps workflows, enabling seamless model deployment and monitoring. Built robust REST APIs and WebSocket channels with 99.9% uptime, while ensuring MiFID II and GDPR compliance. Implemented comprehensive unit tests with PyTest, significantly reducing production bugs, and introduced advanced task scheduling with Celery and RabbitMQ. Used Docker and Terraform to provision IaC for Azure AKS deployments, enhancing scalability and manageability.
Senior Fullstack Engineer at Leobit
August 1, 2022 - PresentLed the development of React and Node.js applications, optimizing onboarding flows and boosting user satisfaction by 30%. Designed scalable RESTful APIs with Express and TypeScript, delivering a 25% performance improvement through optimized data handling. Architected PostgreSQL databases with Drizzle for efficient state management, achieving 99.9% uptime during peak periods. Implemented dynamic microservices and cloud deployment to Azure App Services with Terraform, enabling rapid scaling. Integrated AI capabilities and OpenAI-driven insights, increasing operational efficiency by 20%. Adopted Tailwind CSS and Shadcn to deliver responsive UI, cutting page load times by 50%. Enriched user communications through SendGrid and Vonage APIs, lifting engagement by 35%. Implemented secure payment flows with Stripe, reducing failed transactions by 15%. Fostered cross-team collaboration to resolve integration issues, accelerating releases by 20%. Performed thorough security audits and applied sec
Software Engineer at Innovature
November 1, 2018 - June 1, 2022Architected robust front-end and back-end systems using React, Node, and Express, increasing user onboarding efficiency by 30% through streamlined document workflows. Led the development of event-driven microservices (TypeScript) with PostgreSQL for data management and faster transaction processing (25%). Optimized deployments on Azure App Services with Terraform, reducing rollout time by 40%. Built secure data pipelines with Drizzle and Apache Airflow to support regulatory data exchange and reduce processing errors by 20%. Implemented OAuth2 and Azure AD B2C to strengthen authentication and regulatory compliance, reducing security risks by 50%. Collaborated across teams to ensure timely deliveries (100% on-time). Integrated OpenAI-based features to improve user analytics by 15%. Created UI components with Tailwind and Shadcn to accelerate frontend development by 30%. Used SendGrid for transactional emails with 95% deliverability. Leveraged Stripe and Vonage for payments and communicat
Software Developer at Wizcorp
April 1, 2015 - November 1, 2018Developed high-performance backend services for trading using Node, Express, and PostgreSQL, achieving a 30% increase in transaction efficiency. Built a real-time data streaming solution using WebSockets and Redis to provide up-to-the-minute market data, speeding decision-making by 50%. Designed robust REST APIs and front-end integrations with React and TypeScript. Ensured MiFID II and GDPR compliance, maintaining service availability above 99.9%. Automated testing with PyTest and mock servers, reducing deployment times from 2 days to an average of 12 hours. Implemented advanced job queues with Celery and RabbitMQ, improving task processing by 40%. Architected systems that dynamically scaled with demand during peak trading, increasing reliability by 60%. Collaborated with cross-functional teams to deliver projects on schedule and fostered an agile environment.
Senior QA Engineer at Leobit
August 1, 2022 - PresentLed backend and QA initiatives in Python-based services (FastAPI) to streamline document automation, onboarding, and reporting workflows, achieving a 25% reduction in processing time. Improved asynchronous processing of financial transactions via Celery and Redis, boosting throughput by 40%. Directed deployment and management of microservices on Azure App Services with Terraform, delivering 99.9% uptime. Built data pipelines for regulatory reporting using Airflow and Azure Functions, increasing reporting accuracy by 30%. Executed security assessments and integrated OAuth2 and Azure AD B2C to strengthen authentication and reduce vulnerabilities by 50%. Collaborated with cross-functional teams to address integration and compliance, contributing to a 15% uplift in deployment frequency.
Education
Bachelor's Degree in Computer Science at Keio University
January 1, 2010 - January 1, 2015Bachelor's Degree in Computer Science at Keio University
January 1, 2010 - January 1, 2015Bachelor’s Degree in Computer Science at Keio University
January 1, 2010 - January 1, 2015Bachelor's Degree in Computer Science at Keio University
January 1, 2010 - December 31, 2015Bachelor's Degree in Computer Science at Keio University
January 1, 2010 - January 1, 2015Bachelor’s Degree in Computer Science at Keio University
January 1, 2010 - January 1, 2015Bachelor’s Degree in Computer Science at Keio University
January 1, 2010 - January 1, 2015Qualifications
Industry Experience
Financial Services, Software & Internet, Professional Services, Media & Entertainment, Other, Education
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
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