Gustavo Pares

Lead Engineer with 10+ years of experience designing, modernizing, and maintaining production web applications. Specialized API architecture, third-party integrations, e-commerce, payments, PostgreSQL, automated testing, and legacy-system modernization. Experienced leading engineering teams, mentoring developers, defining technical architecture, improving delivery processes, and translating business requirements into maintainable software.

Lead Engineer / Flutter – Rails API – Ruby on Rails at Mazal & Bracha (2025-10 – 2026-09)

• Architected and built the Ruby on Rails API backend for a greenfield web and mobile platform.
• Designed Rails as the central source of truth for the web application and Flutter client.
• Led the technical decision to use Flutter instead of React Native and contributed directly to mobile development.
• Used AI-assisted development to accelerate dashboard implementation and reduce development effort.

Lead Engineer – React – Next JS at REEF Technology (2024-10 – 2025-10)

• Led development of daily Cost of Goods Sold reporting across vessels operating in Europe, Dubai, and the United States.
• Built automated PDF reporting that transformed financial data into clear cost analytics for business decision-making.
• Directed integrations with multiple food-delivery APIs and built web scrapers to enrich internal analytics.
• Automated manual workflows and established developer onboarding, technical documentation, processes, and delivery timelines.

Ruby on Rails - React at Line 5 (2020-06 – 2024-09)

• Developed and maintained business-critical Rails systems and assumed responsibility for backend infrastructure after the rest of the engineering team departed.
• Independently built an end-to-end trade-show demo experience that contributed to a 43% increase in trade-show sales.
• Managed and mentored 4+ junior developers through code reviews, technical guidance, and development expectations.
• Standardized developer onboarding and authored technical documentation to close major knowledge gaps.

Lead Web Developer – PHP – Shopify – Ruby on Rails - Javascript at PDG Creative (2018-12 – 2020-05)

• Led modernization of the agency web stack from PHP and WordPress toward Ruby on Rails.
• Rebuilt legacy monolithic applications into maintainable Rails codebases and migrated WordPress projects to a custom Rails CMS.
• Reduced reliance on third-party contractors by establishing an efficient in-house Rails development workflow.
• Managed junior developers, performed code review, introduced automated testing, and delivered greenfield, legacy, CMS, and Shopify projects.

Web Developer at New Medio (2015-01 – 2018-11)

• Developed and maintained backend functionality for BMX Racing, implementing features and resolving complex production issues.
• Contributed to frontend and backend development for ICEDOT through its eventual acquisition.
• Built experience in API architecture, deployment pipelines, production support, and Rails best practices while working with senior engineers.
• Worked across greenfield development, legacy applications, custom CMS projects, and third-party integrations.