Mario Gueyraud, Developer in Asuncion, Paraguay
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Mario Gueyraud

Bio

Mario is a software engineer specializing in developing highly scalable and maintainable web pages with a good structure. He focuses on building the front end using CSS, JavaScript, and A11Y while maintaining good performance. Mario enjoys creating delightful user experiences with high-quality code when delivering innovative products.

Portfolio

Vibrant Practice Inc
Next.js, React, Tailwind CSS, React Native, Figma, Radix UI, OpenAI, ChatGPT...
Binti, Inc.
React, JavaScript, CSS, HTML, UI Development, Context API, Figma to React...
Saagas.ai Inc
React, Amazon Web Services (AWS), APIs, SQL, HTML, CSS, JavaScript, Radix UI...

Experience

  • Next.js - 5 years
  • HTML - 5 years
  • React - 5 years
  • REST APIs - 5 years
  • JavaScript - 5 years
  • CSS - 5 years
  • TypeScript - 3 years
  • Remix - 1 year

Preferred Environment

Visual Studio Code (VS Code), MacOS

The most amazing...

...thing I've developed is software for the Avery Dennison company, getting great feedback from their clients.

Work Experience

Full-stack Developer (Frontend-focused)

2025 - 2026
Vibrant Practice Inc
  • Led the evolution of the scheduling system, transitioning to practice-wide appointment types, integrating Cal.com busy-time syncing, enabling multi-provider daily views, and introducing support for in-person care visits alongside virtual visits.
  • Implemented Fullscript integration for supplement plan creation and tracking, enabling clinicians to prescribe, manage, and sync supplement data directly into Medplum-powered patient records for end-to-end care continuity.
  • Built real-time in-person AI scribing powered by Deepgram, streaming visit transcription in fault-tolerant chunks and processing encounters via background jobs to automatically generate structured SOAP notes within the platform.
  • Redesigned and expanded the clinical communication and records experience, enabling clinician-only internal notes, dynamic care team chat management, optimistic messaging, and launching a unified records tab consolidating AI scribes, labs, etc.
Technologies: Next.js, React, Tailwind CSS, React Native, Figma, Radix UI, OpenAI, ChatGPT, Large Language Models (LLMs), Fast Healthcare Interoperability Resources (FHIR), HIPAA Compliance, HIPAA Electronic Data Interchange (EDI), HL7 FHIR Standard, Artificial Intelligence (AI), Mantine, Deepgram, AI Integration, Claude API, AI-generated Code, Claude Code, Cursor AI, Agentic AI, AI Tools, Claude, RESTFul APIs, Node.js, Core Web Vitals, Jest, Healthtech, Medplum, Google Calendar API, Calendars, Mobile Development, Expo, Playwright, Mobile Design, Mobile UI Design, Software Architecture, CI/CD Pipelines, RESTful Web Services, Webhooks, Sentry, Agentic Coding

Front-end React Developer

2024 - 2024
Binti, Inc.
  • Led the development of a high-stakes React demo for a Washington state contract worth eight figures, building critical features like the Intake Screening Tool with decision tree logic and Person Profile pages while maintaining a rapid delivery pace.
  • Engineered reusable layouts and components that accelerated project velocity, documented them in Storybook, and developed full-stack features using Ruby on Rails back-end integration with React front end.
  • Created innovative features, including a Reporter Portal demo and image annotation prototype, and consistently received positive feedback from managers while working under tight deadlines.
Technologies: React, JavaScript, CSS, HTML, UI Development, Context API, Figma to React, Ruby on Rails (RoR), Figma, Radix UI, RESTFul APIs

Senior Full-stack Developer

2023 - 2024
Saagas.ai Inc
  • Developed the landing page and app MVP using Next.js and React, with good practices and accessibility in mind. Utilized Radix UI for complex components and collaborated with Tailwind CSS for styling.
  • Built the entire CI/CD flow and documented all the decisions made from the GitHub Actions to the component libraries for complex components.
  • Enhanced the back end by developing Lambda functions with Python (FastAPI) and deploying them on AWS. Implemented API gateways to enable front-end accessibility.
Technologies: React, Amazon Web Services (AWS), APIs, SQL, HTML, CSS, JavaScript, Radix UI, Tailwind CSS, AWS Lambda, FastAPI, Python, Next.js, AWS Amplify, Amazon S3 (AWS S3), Stripe, Typeform, Full-stack Development, Artificial Intelligence (AI), API Integration, Full-stack, SaaS, Responsive UI, Pixel Perfect, UI Components, User Experience (UX), User Interface (UI), REST, React Router, Responsive Web Design (RWD), Tailwind UI, MongoDB, UI Design, UX Design, Single-page Applications (SPAs), Web Content Accessibility Guidelines (WCAG), NPM, Server-side Rendering (SSR), Single Sign-on (SSO), CSS3, AWS Secrets Manager, Startups, Lambda Functions, Serverless, NoSQL, UI Development, Search Engine Optimization (SEO), AWS Serverless Application Model (SAM), Context API, Figma to React, Figma, Agentic AI, AI Tools, RESTFul APIs, Node.js, Payment Processing, Software Architecture, CI/CD Pipelines, Webhooks

Senior Front-end Engineer / Sanity Expert

2023 - 2023
Tinloof
  • Led the development of SoleRetriever's new blog MVP using Next.js and Sanity, improving website performance and providing content writers with a user-friendly interface for easier content creation.
  • Migrated SoleRetriever's web flow blog to Sanity by creating custom scripts to scrap each article. This resulted in a more efficient content structure within Sanity and reduced the time required for content updates.
  • Developed and implemented a responsive website for Ambassador.io using React components (Remix) and Tinloof's builder, improving user experience.
Technologies: Accessibility, TypeScript, React, Remix, Next.js, Sanity Studio, Figma, Notion, Slack, Vercel, Netlify, Tailwind CSS, Headless CMS, Full-stack Development, Node.js, API Integration, Full-stack, SaaS, Responsive UI, Content Management Systems (CMS), Pixel Perfect, UI Components, Supabase, REST, Responsive Web Design (RWD), Tailwind UI, UI Design, UX Design, Web Content Accessibility Guidelines (WCAG), NPM, Server-side Rendering (SSR), CSS3, Startups, UI Development, Search Engine Optimization (SEO), Context API, Figma to React, RESTFul APIs, Core Web Vitals, CI/CD Pipelines, Performance Optimization, RESTful Web Services

Front-end Developer

2022 - 2023
Belk - Main
  • Fixed bugs and maintained Belk.com's CSS, HTML, and JavaScript, impacting millions of users and always having accessibility and performance in mind.
  • Reduced server-side render time by almost half the time by converting ISML files of Salesforce Commerce Cloud into JavaScript files.
  • Developed integration of Conns and Belk within the Belk.com site so the users can buy Conns products and have installation and haulaway options.
  • Added new components to their design system using Vue and web components, working closely with the design team and co-workers to deliver the best components with a great API.
Technologies: HTML, CSS, JavaScript, APIs, Front-end Development, Vue, API Integration, Responsive UI, SCSS, Pixel Perfect, UI Components, Responsive Web Design (RWD), UI Design, UX Design, Bitbucket, Web Content Accessibility Guidelines (WCAG), CSS3, Large-scale Projects, eCommerce, UI Development, Search Engine Optimization (SEO), Figma, React Native, Core Web Vitals, Performance Optimization

React Developer and Lead Front-end Developer

2021 - 2022
Tonic3
  • Developed a product for Avery Dennison clients using TypeScript and React to enable paginations, tables, filtering options, and charts. Implemented the unit, integration, and end-to-end tests.
  • Changed some features based on the feedback from the company's first customers.
  • Maintained and developed the React component library.
  • Collaborated and held discussions with stakeholders such as product owners to learn about future features to implement.
  • Acted as the lead front-end developer in a small team and was in charge of defining the tasks and estimating them.
Technologies: JavaScript, TypeScript, HTML, CSS, Material UI, React, Sketch, Storybook, Front-end, REST APIs, Front-end Development, APIs, Mapbox, Dashboards, Data Visualization, API Integration, Responsive UI, Docker, Pixel Perfect, UI Components, User Experience (UX), User Interface (UI), React Router, REST, Responsive Web Design (RWD), UI Design, UX Design, Single-page Applications (SPAs), NPM, Webpack, CSS3, Data Analytics, Docker Compose, UI Development, Context API, Figma to React, Figma, Dashboard Development, Software Architecture, CI/CD Pipelines

UI and React Developer

2020 - 2021
Teixido
  • Developed and implemented new features of an insurance company's web page using React and PHP with CodeIgniter on the back end.
  • Maintained the design system with Sass and ITCSS with BEM class naming for a renowned newspaper web page and implemented small React components for lazy loading patterns that improved the web performance.
  • Optimized another newspaper website using lazy loading of React components, reducing the initial load time and improving the page's download size.
Technologies: Sass, CSS, React, HTML, JavaScript, Performance, Front-end, Sketch, REST APIs, Front-end Development, APIs, PHP, API Integration, Responsive UI, Redux, SCSS, Pixel Perfect, UI Components, Bootstrap, jQuery, User Experience (UX), User Interface (UI), React Router, REST, Responsive Web Design (RWD), UI Design, Single-page Applications (SPAs), NPM, Webpack, CSS3, Laravel, UI Development, Search Engine Optimization (SEO), Context API, Figma to React, React Native, RESTFul APIs, Core Web Vitals, Web Design, RESTful Web Services

Intern

2017 - 2018
Teixido
  • Learned the basics of web development: HTML, CSS, JavaScript, etc.
  • Developed web pages to demonstrate the things I learned.
  • Added features to a web page of a very renowned bank and insurance company in my country and some CRUD functionalities.
Technologies: CSS, HTML5, JavaScript, Front-end Development, APIs, API Integration, Responsive UI, Pixel Perfect, UI Components, React Router, Responsive Web Design (RWD), UI Design, NPM, Webpack, CSS3, Search Engine Optimization (SEO), Context API, Core Web Vitals

Experience

5 Dias S.A.

https://www.5dias.com.py/
A newspaper web page that allowed users to read articles and great information about finances and business.

I delivered the mockups using Sass, HTML, CSS (BEM and ITCSS architecture), and JavaScript. I also created web components using React and improved the performance by creating lazy loading images. The web page had more than 10,000 users active on a daily basis.

Hoy S.A.

https://www.hoy.com.py/
A website enabling users to read articles and other information about the country and world.

I improved the website performance by creating lazy loading components with React and delivered mockups for new features using Sass, HTML, CSS, and JavaScript. The web page had more than 60,000 users active daily.

La Consolidada S.A.

https://www.consolidada.com.py/
A web app for insurance company, allowing their clients to register any accident requiring the insurer.

I created the React components for the new features and integrated them with the back-end part.

Eco Colegio

A landing page for a school.

I completed the mockups with Sass, HTML, CSS, and JavaScript, using a CSS library called Bulma. I developed it following the best practices and always considering accessibility and performance.

Shopping del Sol

https://www.shoppingdelsol.com.py/
A web page for one of the well-known shopping malls in the country that shows information about the stores, such as location, products, and more. Also, it shows information about the cinema inside the mall, like movies offered and available seats. I was in charge of adding some features and the whole page re-design (the mockup).

Marketing Website for a SaaS

https://www.getambassador.io/
A marketing website for a Kubernetes service, where I was the full-stack developer who added features to the website using Remix and also worked with the client to add any specifications to the CMS used (Sanity).

Education

2019 - 2022

Bachelor's Degree in Computer Science

Universidad Nacional de Asuncion - Asuncion, Paraguay

Skills

Libraries/APIs

React, React Router, Context API, Node.js, REST APIs, jQuery, Claude API, Google Calendar API, CSSinJS, Vue, Highcharts, AWS Amplify, Stripe, Typeform, Mantine, Playwright

Tools

Figma, Sketch, Git, GitHub, Bitbucket, NPM, Webpack, Claude Code, Claude, Expo, Sentry, ITCSS, Notion, Slack, Docker Compose, ChatGPT

Languages

JavaScript, TypeScript, HTML, CSS, CSS3, SCSS, Sass, HTML5, SQL, Python, PHP

Frameworks

Next.js, Tailwind CSS, Bootstrap, Remix, Redux, React Native, Material UI, Bulma, Laravel, AWS Serverless Application Model (SAM), Ruby on Rails (RoR), Jest

Paradigms

Responsive Web Design (RWD), Agile, REST, UI Design, UX Design, Search Engine Optimization (SEO), Mobile Development, BEM, Fast Healthcare Interoperability Resources (FHIR), HIPAA Compliance, HL7 FHIR Standard, Mobile Design, Mobile UI Design

Platforms

Visual Studio Code (VS Code), Medplum, MacOS, Sanity Studio, Vercel, Netlify, Mapbox, Amazon Web Services (AWS), AWS Lambda, Docker

Storage

Amazon S3 (AWS S3), MongoDB, NoSQL

Industry Expertise

Web Design

Other

Front-end, APIs, API Integration, Responsive UI, Pixel Perfect, UI Components, Single-page Applications (SPAs), UI Development, Figma to React, Core Web Vitals, Agentic Coding, Front-end Development, Accessibility, Radix UI, Full-stack Development, Full-stack, SaaS, Content Management Systems (CMS), User Experience (UX), User Interface (UI), Tailwind UI, Web Content Accessibility Guidelines (WCAG), Server-side Rendering (SSR), Startups, Large-scale Projects, eCommerce, AI Integration, AI-generated Code, Cursor AI, Agentic AI, AI Tools, RESTFul APIs, Healthtech, Calendars, Dashboard Development, Software Architecture, CI/CD Pipelines, Performance Optimization, RESTful Web Services, Webhooks, Performance, Storybook, Dashboards, Data Visualization, FastAPI, Headless CMS, Artificial Intelligence (AI), Supabase, Single Sign-on (SSO), AWS Secrets Manager, Data Analytics, Lambda Functions, Serverless, OpenAI, Large Language Models (LLMs), HIPAA Electronic Data Interchange (EDI), Deepgram, Payment Processing

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