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Senior Software Engineer specializing in full-stack web development and AI-powered software solutions, with deep experience building scalable, cloud-native systems and resilient microservices. I focus on delivering reliable APIs, event-driven workflows, and production-grade experiences using modern web stacks and strong engineering practices. I also build LLM-integrated automation and RAG-style solutions to turn business data into actionable insights and streamline repetitive engineering and support workflows. My work spans frontend performance, backend reliability (idempotency, retries, deduplication), and end-to-end CI/CD and observability—partnering closely across product, design, data, QA, and platform teams.…Senior Software Engineer specializing in full-stack web development and AI-powered software solutions, with deep experience building scalable, cloud-native systems and resilient microservices. I focus on delivering reliable APIs, event-driven workflows, and production-grade experiences using modern web stacks and strong engineering practices. I also build LLM-integrated automation and RAG-style solutions to turn business data into actionable insights and streamline repetitive engineering and support workflows. My work spans frontend performance, backend reliability (idempotency, retries, deduplication), and end-to-end CI/CD and observability—partnering closely across product, design, data, QA, and platform teams.

Mario Harper

Software Engineer, Full Stack Developer, Back-End Developer, +2

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Senior Software Engineer specializing in full-stack web development and AI-powered software solutions, with deep experience building scalable, cloud-native systems and resilient microservices. I focus on delivering reliable APIs, event-driven workflows, and production-grade experiences using modern web stacks and strong engineering practices. I also build LLM-integrated automation and RAG-style solutions to turn business data into actionable insights and streamline repetitive engineering and support workflows. My work spans frontend performance, backend reliability (idempotency, retries, deduplication), and end-to-end CI/CD and observability—partnering closely across product, design, data, QA, and platform teams.…Senior Software Engineer specializing in full-stack web development and AI-powered software solutions, with deep experience building scalable, cloud-native systems and resilient microservices. I focus on delivering reliable APIs, event-driven workflows, and production-grade experiences using modern web stacks and strong engineering practices. I also build LLM-integrated automation and RAG-style solutions to turn business data into actionable insights and streamline repetitive engineering and support workflows. My work spans frontend performance, backend reliability (idempotency, retries, deduplication), and end-to-end CI/CD and observability—partnering closely across product, design, data, QA, and platform teams.

Available to hire

Senior Software Engineer specializing in full-stack web development and AI-powered software solutions, with deep experience building scalable, cloud-native systems and resilient microservices. I focus on delivering reliable APIs, event-driven workflows, and production-grade experiences using modern web stacks and strong engineering practices.

I also build LLM-integrated automation and RAG-style solutions to turn business data into actionable insights and streamline repetitive engineering and support workflows. My work spans frontend performance, backend reliability (idempotency, retries, deduplication), and end-to-end CI/CD and observability—partnering closely across product, design, data, QA, and platform teams.

Skills

Experience Level

Expert

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Intermediate

Intermediate

Language

Work Experience

Senior Software Engineer at Square

September 1, 2022 - February 1, 2026

Led end-to-end development of seller-facing commerce and payments experiences using React, Next.js, TypeScript, and Node.js. Designed backend services and REST APIs for payment, order, catalog, and customer workflows, applying idempotent processing and clear service boundaries. Built responsive seller dashboards with reusable React components and optimized state management. Developed event-driven integrations and webhook processing for real-time payment and order updates, including retry, deduplication, validation, and failure-handling patterns for resilient asynchronous workflows. Improved performance by optimizing PostgreSQL queries, introducing Redis caching, tuning API communication, and profiling critical transaction paths to reduce latency under peak workloads. Containerized services with Docker and Kubernetes and strengthened CI/CD pipelines for safer deployments and faster recovery. Contributed to AI-powered seller experiences and internal automation using Python and LLM-based

Software Engineering Manager at The Knot Worldwide

May 1, 2019 - September 1, 2022

Built and enhanced full-stack shopping planning and marketplace experiences using React, TypeScript, Node.js, REST APIs, and GraphQL. Developed reusable frontend components for vendor discovery, profiles, planning tools, and marketplace interactions. Designed and maintained scalable backend services and APIs connecting user accounts, vendor data, lead-management workflows, and third-party integrations. Modeled and optimized MongoDB-backed data with indexing and aggregation to improve reliability and responsiveness. Improved web performance and discoverability by reducing bundle size and optimizing rendering and API behavior for consumer-facing pages. Contributed to event-driven and asynchronous workflows for notifications and integrations using messaging patterns, retries, validation, and idempotent processing. Strengthened engineering quality with automated unit/integration testing, code reviews, incident troubleshooting, and Agile delivery while mentoring teammates.

Software Engineer at XO Group Inc.

April 1, 2017 - April 1, 2019

Developed Node.js microservices and REST APIs for vendor discovery, planning, and internal integrations. Connected React frontends to event-driven services for marketplace activity, notifications, and partner data. Supported AWS production apps with monitoring, caching, performance tuning, and incident troubleshooting. Used Jasmine, TDD, code reviews, and A/B testing to improve quality across frequent product releases.

Software engineer at Volusion, LLC

March 1, 2016 - April 1, 2017

Developed and maintained merchant-facing e-commerce features using JavaScript, HTML/CSS, and SQL Server for storefront, catalog, customer, and order-management workflows. Debugged and tested checkout, catalog, and administrative features, optimized SQL queries and client-side code, and contributed to code reviews and release support. Participated in continuous platform improvements and quality efforts.

Junior software engineer at 3Seed and CAI

April 1, 2013 - March 1, 2016

Created dynamic front-end web development. Implemented relational databases using MS SQL Server.