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I'm a Senior Software Engineer with over a decade of experience building data-intensive web platforms and scalable applications, including analytics-driven finance systems and dynamic funnel-based user interfaces. I specialize in React, TypeScript, and backend services using Node.js and Python, delivering cloud-native solutions on AWS. I focus on data-driven user experiences, performance optimization, and building reliable full-stack architectures that support high-volume processing and business-critical workflows.…I'm a Senior Software Engineer with over a decade of experience building data-intensive web platforms and scalable applications, including analytics-driven finance systems and dynamic funnel-based user interfaces. I specialize in React, TypeScript, and backend services using Node.js and Python, delivering cloud-native solutions on AWS. I focus on data-driven user experiences, performance optimization, and building reliable full-stack architectures that support high-volume processing and business-critical workflows.

Hiro Kowalski

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

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I'm a Senior Software Engineer with over a decade of experience building data-intensive web platforms and scalable applications, including analytics-driven finance systems and dynamic funnel-based user interfaces. I specialize in React, TypeScript, and backend services using Node.js and Python, delivering cloud-native solutions on AWS. I focus on data-driven user experiences, performance optimization, and building reliable full-stack architectures that support high-volume processing and business-critical workflows.…I'm a Senior Software Engineer with over a decade of experience building data-intensive web platforms and scalable applications, including analytics-driven finance systems and dynamic funnel-based user interfaces. I specialize in React, TypeScript, and backend services using Node.js and Python, delivering cloud-native solutions on AWS. I focus on data-driven user experiences, performance optimization, and building reliable full-stack architectures that support high-volume processing and business-critical workflows.

Available to hire

I’m a Senior Software Engineer with over a decade of experience building data-intensive web platforms and scalable applications, including analytics-driven finance systems and dynamic funnel-based user interfaces.

I specialize in React, TypeScript, and backend services using Node.js and Python, delivering cloud-native solutions on AWS. I focus on data-driven user experiences, performance optimization, and building reliable full-stack architectures that support high-volume processing and business-critical workflows.

Skills

Experience Level

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Work Experience

Senior Software Engineer at BI4All

August 1, 2023 - Present

Designed and implemented a scalable financial analytics platform using React, TypeScript, and Node.js, enabling real-time data visualization and improving user engagement metrics by 35%. Built modular front-end architecture with reusable components and Redux-based state management, reducing code duplication by 40% and improving maintainability across configurations. Built backend microservices in Node.js and Python to handle high-volume financial data pipelines (over 2 million transactions daily) with latency improvements of 28%. Integrated AWS-native solutions (Lambda, S3, ECS) to support auto-scaling and fault tolerance, increasing system availability to 99.9% under peak loads. Optimized PostgreSQL and DynamoDB schemas to improve query performance by 32%. Enhanced performance with lazy loading, code-splitting, and caching, achieving 45% faster page loads. Integrated AI-driven features via OpenAI API to generate dynamic insights for end users. Collaborated in an Agile environment to d

Software Engineer at Softwire

March 1, 2020 - August 31, 2023

Developed a scalable funnel-based web platform using React and TypeScript, enabling dynamic user journeys and improving conversion rates by 27%. Implemented backend services with Node.js and Express to support real-time scheduling, billing, and third-party integrations while maintaining high throughput under concurrent usage. Designed efficient RESTful APIs and asynchronous workflows to handle large-scale user interactions, reducing system response time by 30% and improving reliability. Leveraged AWS (Lambda and RDS) to deploy scalable cloud infrastructure, enabling seamless horizontal scaling and improved deployment efficiency. Enhanced data processing and validation with structured schemas and middleware, decreasing data inconsistencies by 25%. Built responsive, accessible UI components with security and privacy measures aligned with compliance requirements. Optimized PostgreSQL queries and indexing for better reporting and dashboard performance.

Software Engineer at Comarch

July 1, 2019 - March 31, 2020

Developed core features for a banking and BI platform using JavaScript and backend services, enabling secure account management and transaction processing for enterprise clients. Implemented real-time financial data tracking and reporting modules, improving data accuracy and reducing reconciliation delays by 20%. Designed integration layers for external financial systems using REST APIs, enhancing interoperability and data exchange. Built structured data validation and rule-based processing systems to support regulatory compliance and audit requirements. Optimized SQL queries and Oracle schemas, improving system performance under heavy workloads. Supported automation workflows for financial reporting and analytics, enabling faster decision-making across business units. Collaborated with cross-functional teams to deliver stable and maintainable solutions within strict financial constraints.

Software Engineer at Future Processing

October 1, 2018 - July 31, 2019

Developed a real-time data delivery platform using JavaScript and backend services, providing live updates and improving data availability for end users. Implemented interactive dashboards and visualization components, enhancing user experience and enabling quick insights from streaming data. Built data ingestion pipelines to process external data sources efficiently, reducing latency in data updates by 18%. Supported secure authentication and session management mechanisms to ensure reliable access control for users. Integrated third-party APIs for real-time information exchange, improving platform functionality and data coverage. Maintained database operations using MySQL, ensuring consistent data integrity and optimized query performance. Assisted in debugging and performance tuning of applications, contributing to overall system stability and reduced downtime.