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I'm Leonardo Agostini, a Senior Frontend Engineer with 5 years of experience building web and mobile products using React, React Native, and TypeScript. I have a strong foundation in frontend architecture, performance optimization, design systems, and micro-frontend patterns, with hands-on experience in unit and integration testing, observability with Sentry, and improving delivery pipelines. I've contributed to real-time chat, CRM, and core banking products, with a focus on scalability, maintainability, and a great user experience. I enjoy collaborating with product and design teams, shaping design systems and UI/UX quality, and creating reusable components and AI-assisted development workflows.…I'm Leonardo Agostini, a Senior Frontend Engineer with 5 years of experience building web and mobile products using React, React Native, and TypeScript. I have a strong foundation in frontend architecture, performance optimization, design systems, and micro-frontend patterns, with hands-on experience in unit and integration testing, observability with Sentry, and improving delivery pipelines. I've contributed to real-time chat, CRM, and core banking products, with a focus on scalability, maintainability, and a great user experience. I enjoy collaborating with product and design teams, shaping design systems and UI/UX quality, and creating reusable components and AI-assisted development workflows.

Leonardo Agostini

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

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I'm Leonardo Agostini, a Senior Frontend Engineer with 5 years of experience building web and mobile products using React, React Native, and TypeScript. I have a strong foundation in frontend architecture, performance optimization, design systems, and micro-frontend patterns, with hands-on experience in unit and integration testing, observability with Sentry, and improving delivery pipelines. I've contributed to real-time chat, CRM, and core banking products, with a focus on scalability, maintainability, and a great user experience. I enjoy collaborating with product and design teams, shaping design systems and UI/UX quality, and creating reusable components and AI-assisted development workflows.…I'm Leonardo Agostini, a Senior Frontend Engineer with 5 years of experience building web and mobile products using React, React Native, and TypeScript. I have a strong foundation in frontend architecture, performance optimization, design systems, and micro-frontend patterns, with hands-on experience in unit and integration testing, observability with Sentry, and improving delivery pipelines. I've contributed to real-time chat, CRM, and core banking products, with a focus on scalability, maintainability, and a great user experience. I enjoy collaborating with product and design teams, shaping design systems and UI/UX quality, and creating reusable components and AI-assisted development workflows.

Available to hire

I’m Leonardo Agostini, a Senior Frontend Engineer with 5 years of experience building web and mobile products using React, React Native, and TypeScript. I have a strong foundation in frontend architecture, performance optimization, design systems, and micro-frontend patterns, with hands-on experience in unit and integration testing, observability with Sentry, and improving delivery pipelines.

I’ve contributed to real-time chat, CRM, and core banking products, with a focus on scalability, maintainability, and a great user experience. I enjoy collaborating with product and design teams, shaping design systems and UI/UX quality, and creating reusable components and AI-assisted development workflows.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Language

Portuguese

Fluent

English

Advanced

Work Experience

Senior Frontend Engineer at ONZ Finance

February 1, 2025 - Present

Advanced release workflows via CI/CD improvements, decoupled frontend and backend releases with feature flags, improved GitHub Actions pipelines with caching and validation enhancements, strengthened observability with customer- and version-level Sentry monitoring, automated release documentation in n8n, and contributed to a shared design system library with Storybook to standardize UI/UX and enable AI-assisted development. Implemented a runtime endpoint override mechanism for dynamic environment testing and supported a React Native app for feature delivery and push notifications.

Development Specialist at FITE C

June 1, 2023 - February 1, 2025

Reduced frontend bundle size by 20% via dependency analysis and frontend optimization; consolidated frontend repos into a single maintainable product; built an embeddable chat widget under 820 KB; delivered a high-performance FAQ platform with SEO benefits; reworked the after-sales portal contributing to a 20%+ rise in user satisfaction; advanced design system/UI quality; expanded unit and integration test coverage; contributed to micro-frontend architectures for modularity and scalability; performed load testing to achieve cost savings.

Junior Web Developer III at M8 Systems

January 1, 2022 - May 31, 2023

Contributed to frontend development across multiple projects, supporting the evolution of web applications and collaborative delivery with design and product teams.

Junior Web Developer III at M8 Sistemas

January 1, 2022 - May 1, 2023

Frontend development with focus on modular architecture, UI implementation, and collaboration with product and design teams to deliver scalable features.

Junior Web Developer at Aphesis TI

February 1, 2021 - January 31, 2022

Early-career frontend role supporting UI development, bug fixes, and collaboration with designers to implement frontend components.