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I'm a detail-oriented Senior Software Engineer with 8+ years of experience delivering full-stack and frontend-focused web products. I enjoy building with JavaScript and TypeScript, especially React and Node.js, and I’ve worked with Next.js, REST APIs, and design systems across distributed teams. I mentor junior developers through onboarding and PR reviews, help surface frontend constraints early with product and design, and contribute to migrations from JavaScript to TypeScript. I'm based in Lima, Peru, work remotely with US and global teams, and I thrive on delivering maintainable, user-friendly software through CI/CD-driven releases.…I'm a detail-oriented Senior Software Engineer with 8+ years of experience delivering full-stack and frontend-focused web products. I enjoy building with JavaScript and TypeScript, especially React and Node.js, and I’ve worked with Next.js, REST APIs, and design systems across distributed teams. I mentor junior developers through onboarding and PR reviews, help surface frontend constraints early with product and design, and contribute to migrations from JavaScript to TypeScript. I'm based in Lima, Peru, work remotely with US and global teams, and I thrive on delivering maintainable, user-friendly software through CI/CD-driven releases.

Harold Leon Diaz Sr.

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

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I'm a detail-oriented Senior Software Engineer with 8+ years of experience delivering full-stack and frontend-focused web products. I enjoy building with JavaScript and TypeScript, especially React and Node.js, and I’ve worked with Next.js, REST APIs, and design systems across distributed teams. I mentor junior developers through onboarding and PR reviews, help surface frontend constraints early with product and design, and contribute to migrations from JavaScript to TypeScript. I'm based in Lima, Peru, work remotely with US and global teams, and I thrive on delivering maintainable, user-friendly software through CI/CD-driven releases.…I'm a detail-oriented Senior Software Engineer with 8+ years of experience delivering full-stack and frontend-focused web products. I enjoy building with JavaScript and TypeScript, especially React and Node.js, and I’ve worked with Next.js, REST APIs, and design systems across distributed teams. I mentor junior developers through onboarding and PR reviews, help surface frontend constraints early with product and design, and contribute to migrations from JavaScript to TypeScript. I'm based in Lima, Peru, work remotely with US and global teams, and I thrive on delivering maintainable, user-friendly software through CI/CD-driven releases.

Available to hire

I’m a detail-oriented Senior Software Engineer with 8+ years of experience delivering full-stack and frontend-focused web products. I enjoy building with JavaScript and TypeScript, especially React and Node.js, and I’ve worked with Next.js, REST APIs, and design systems across distributed teams.

I mentor junior developers through onboarding and PR reviews, help surface frontend constraints early with product and design, and contribute to migrations from JavaScript to TypeScript. I’m based in Lima, Peru, work remotely with US and global teams, and I thrive on delivering maintainable, user-friendly software through CI/CD-driven releases.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Language

Spanish; Castilian

Fluent

English

Advanced

Work Experience

Sr. Software Engineer at Keller Williams Realty LLC

January 1, 2025 - Present

Senior engineer contributions to migrating projects from JavaScript to TypeScript; mentored junior developers through onboarding, pairing, and PR reviews; promoted releases to QA and production using CI/CD; collaborated with distributed teams across time zones and English proficiency to deliver UI and system integrations within the Command platform.

Software Engineer at Keller Williams Realty LLC

December 1, 2023 - April 1, 2025

Contributed to the company design system and React features within Command CRM; launched Kelle Guides; coordinated with cross-functional teams; delivered maintainable UI changes and integrations with existing Command patterns and releases.

Software Engineer at Experis Peru

January 1, 2019 - November 1, 2023

Full-stack work on an electronic invoicing platform for business clients: incident resolution, feature delivery, and end-to-end flows in production. Backend focus: integrated internal services with Peru's SUNAT for electronic documents—external integrations, format and rule requirements, and team coordination as regulations changed. Collaborated with internal stakeholders on requirements, documentation, and tested releases to reduce risk on compliance-sensitive work. Gained first production experience with React.js while supporting existing CRM/invoicing UIs and workflows.

Software Engineer at Facturactiva

January 1, 2017 - January 1, 2019

Developed and maintained web apps for invoicing; supported CRM/invoicing UIs and workflows; collaborated with senior devs on bugs, new features, and code reviews.

Intern at Unified Group Online

January 1, 2015 - January 1, 2017

Gained experience in server setup, infrastructure, and automation; built server-side PHP CRM modules; contributed to automation scripts in C/C++; front-end web app work.