Juan is available for hire

Juan Mendoza

Verified Expert in Engineering

Software Engineering Developer

Bilbao, Spain

Toptal member since November 9, 2022

Expertise

Web Development Software Development Back-end Developers Full-stack Code Review API SaaS Front End Cloud Architecture Dashboard

Bio

Juan is a self-motivated software engineer and a certified AWS architect. With more than 14 years of experience in software engineering, leading and participating in successful cross-functional teams, Juan loves to work in close collaboration with product and design teams to achieve company goals and OKRs.

Portfolio

Gartner

React, Next.js, NPM, TypeScript, CircleCI, CI/CD Pipelines, GitHub, Bitbucket...

Bilt Technologies Inc

TypeScript, React, JavaScript, Component Libraries, Next.js, Turborepo, Turbo...

Hearst - Zynx Health

JavaScript, React, Java, Groovy, NoSQL, MySQL, PostgreSQL, Svelte, MarkLogic...

Experience

Software Engineering - 14 years
React - 10 years
PostgreSQL - 9 years
Microservices - 7 years
Amazon Web Services (AWS) - 7 years
AI Integration - 5 years
Next.js - 4 years
Kotlin - 4 years

Preferred Environment

Spring Boot, Java, Kotlin, Node.js, React, Amazon Web Services (AWS), Kubernetes, Terraform, PostgreSQL, Next.js, Data Modeling, Supabase, APIs

The most amazing...

...projects I've delivered helped companies reach their goals by splitting monolith systems into microservices or creating scalable solutions.

Work Experience

Lead Full-stack & Architecture Engineer

2023 - PRESENT

Gartner

Led the full-stack modernization of an enterprise networking platform using Next.js, React, TypeScript, Node.js, Go, and AWS, reducing critical page latency from ~20s to ~0.9s.
Re-architected key front-end rendering and data-loading paths, replacing slow client-side flows with optimized Next.js rendering, cached API access patterns, and leaner payload delivery.
Built developer-environment automation with Homebrew and shell tooling, reducing new-engineer setup time from around 4 days to less than 1 hour and improving onboarding reliability across the team.
Optimized CI/CD workflows across GitHub Actions, CircleCI, and AWS CDK, parallelizing test execution, enforcing build validation across projects, and reducing release-cycle time from around 2 hours to about 5 minutes.
Authored AWS CDK infrastructure for microservices, SQS queues, DynamoDB tables, and Lambda-based workers, standardizing repeatable infrastructure provisioning for cloud-native services.
Built back-end services in Go and Node.js for Gartner Peer Community, supporting search indexing, authentication flows, and new product capabilities across the platform.
Implemented a Playwright and TypeScript E2E testing framework using Page Object Models, covering core user journeys and improving regression protection across major site flows.
Established engineering quality gates across linting, type safety, test execution, and CI build validation, raising code-quality standards without slowing delivery velocity.
Led internal workshops for front-end engineers on Playwright, TypeScript, Next.js, and maintainable E2E testing practices, helping standardize testing patterns across the team.
Created a scalable React and TypeScript component library aligned with Gartner’s design system, improving UI consistency, reuse, and delivery speed across product teams.

Technologies: React, Next.js, NPM, TypeScript, CircleCI, CI/CD Pipelines, GitHub, Bitbucket, CSS, HTML, JavaScript, Go, Shell, Playwright, E2E Testing, Jest, Amazon Web Services (AWS), Amazon S3 (AWS S3), Amazon Elastic Container Registry (ECR), Amazon Elastic Container Service (ECS), Amazon CloudFront CDN, MongoDB, DocumentDB, Amazon EKS, Technical Leadership, Automation, Containerization, Containers, Responsive Web Design (RWD), HTML5, Leadership, Full-stack Development, SQL, AWS Lambda, AWS Fargate, CSS3, Storybook, OpenTelemetry, Solution Architecture, Microservices Architecture, Front-end Architecture, API Integration, Web Development, User Experience (UX), User Interface (UI), Data Modeling, APIs, Chart.js, Dashboards, Analytics, Charts, Contentful, Headless CMS, MySQL, Front-end Development, Event-driven Architecture, Single-page Applications (SPAs), Amazon API Gateway, Microservices, Distributed Systems, Web Architecture, Back-end, DevOps, Deployment, Git, Distributed Architecture, MERN Stack, Content Management Systems (CMS), Databases, Query Optimization, API Design, Amazon Simple Queue Service (SQS), Jenkins, Cloud Infrastructure, Software Design, Integration, GraphQL, GraphQL API, Back-end Development, Google SEO, Search Engine Optimization (SEO), UI Design, UX Design, Google, Seos, Agile Software Development, AI Agents, Large Language Models (LLMs), Minimum Viable Product (MVP), ChatGPT, Redis, Message Bus, CSV, WebSockets, Ruby on Rails (RoR), Apache Kafka, Browser Automation, ECS, Canvas, Generative Artificial Intelligence (GenAI), AI Tools, UI Components, Product Development, Elasticsearch, Infrastructure as Code (IaC), JSON-LD, Sitemaps, Data Architecture, RESTFul APIs, Site Speed Optimization, Legacy Code, OWASP, UI Development, AI Integration, End-to-end Implementation (E2E), Epic, SMS, AI-assisted Development, Agentic Engineering, Claude Code, Performance Optimization, AI-generated Code, Artificial Intelligence (AI), Back-end Architecture, JSON API, Cloud Platforms, Role-based Access Control (RBAC), Webhooks, Claude, Scalability, Web Scalability, Web UI Design, API Access Control, API Development, Cloud Architecture, PostgreSQL, REST APIs, API Backwards Compatibility, SSH, Agentic AI, LLM Integration, Google Analytics, Tailwind CSS, Astro, Zod, Lighthouse, React Testing Library, Web, Serverless, Third-party APIs, Software Development, System Architecture, Cloudflare, JSON, Express.js, Data Pipelines, Code Review, Security, Code Auditing, Server-side Programming, System Design, System Integration, Technical Architecture, Agentic Coding, Supabase Auth, General Data Protection Regulation (GDPR), Multi-tenant Architecture, SaaS, Authentication, Vibe Coding, Scrum, Product Requirements Documentation (PRD), System Development Life Cycle (SDLC), GitHub Copilot, Planning, Agile, DB, Flutter, Prisma, Documentation, Amazon DynamoDB, Hooks, Amazon Simple Notification Service (SNS), JSON Web Tokens (JWT), Drizzle ORM

Senior Full-stack & Azure Systems Engineer

2025 - 2026

Bilt Technologies Inc

Led a platform-wide front-end performance and developer-experience initiative across 8+ Next.js applications deployed on Vercel and AWS, optimizing build and development workflows and reducing local compile times by around 90%.
Refactored legacy build configuration, framework settings, and shared tooling layers across 8 parallel repositories, improving Next.js hot reload latency from around 100s to around 15s and significantly reducing developer feedback-loop time.
Executed a coordinated upgrade of all 8 Next.js applications from v15 to v16, validating compatibility across shared packages, build pipelines, routing behavior, and runtime configuration without introducing production regressions.
Rolled out Turbopack across the full Next.js application portfolio, improving local development performance by ~8x and reducing production build times by ~4x.
Migrated the platform from ESLint and Prettier to Biome.js across 8+ repositories, consolidating linting and formatting into a faster unified toolchain and improving static-analysis execution speed by about 15x.
Standardized Next.js image optimization, cache-control strategy, TTL policies, and asset parameterization across multiple applications, increasing image cache hit rates to above 90% and improving front-end delivery performance.

Technologies: TypeScript, React, JavaScript, Component Libraries, Next.js, Turborepo, Turbo, Go, Azure, Cursor AI, OWASP, UI Development, End-to-end Implementation (E2E), Epic, SMS, AI-assisted Development, Agentic Engineering, Claude Code, Performance Optimization, AI-generated Code, Artificial Intelligence (AI), Back-end Architecture, JSON API, Cloud Platforms, Role-based Access Control (RBAC), Webhooks, Claude, Scalability, Web Scalability, Fintech, Web UI Design, API Access Control, API Development, Cloud Architecture, Linux, API Backwards Compatibility, Agentic AI, LLM Integration, Google Analytics, Zod, Lighthouse, Web, Third-party APIs, Software Development, System Architecture, Cloudflare, JSON, Express.js, Code Review, Security, Code Auditing, Server-side Programming, System Design, System Integration, Technical Architecture, Agentic Coding, Claude API, Supabase Auth, Multi-tenant Architecture, SaaS, Authentication, Vibe Coding, Scrum, Product Requirements Documentation (PRD), System Development Life Cycle (SDLC), GitHub Copilot, Planning, Agile, DB, Flutter, Prisma, Spring, REST APIs, Documentation, Auditing, Anthropic, JSON Web Tokens (JWT)

Senior Full-stack Developer

2024 - 2025

Hearst - Zynx Health

Helped build a modern clinical content management platform for evidence-based medical content, replacing legacy workflows with a faster, more maintainable SvelteKit, Svelte 5, and TypeScript application.
Led development of complex authoring workflows for creating, editing, reviewing, versioning, publishing, and managing structured healthcare content used by clinical and editorial teams.
Implemented high-value editorial features including auto-save, collaborative editing, inline comments, content reviews, version history, previews, search, filtering, and inline notes.
Built clean, responsive, production-grade UI components for complex medical content structures, balancing usability, maintainability, and workflow accuracy.
Designed and implemented RESTful APIs using Grails, Spring Boot, and AWS-backed services to support clinical content management, editorial workflows, and structured data operations.
Collaborated with DevOps on Docker-based containerization and deployments across Amazon ECS and Kubernetes, improving release consistency and production readiness.
Worked across AWS, Kubernetes, Redshift, GitLab CI/CD, Grails, Spring Boot, SvelteKit, Svelte 5, and TypeScript in a healthcare-focused product environment where correctness, auditability, and content integrity were critical.

Technologies: JavaScript, React, Java, Groovy, NoSQL, MySQL, PostgreSQL, Svelte, MarkLogic, SvelteKit, CSS, TypeScript, Web Architecture, NestJS, DevOps, Deployment, Git, Distributed Architecture, MERN Stack, Content Management Systems (CMS), Databases, Cloud Infrastructure, Software Design, Integration, Back-end Development, UI Design, UX Design, Google, Seos, Agile Software Development, AI Agents, Large Language Models (LLMs), Minimum Viable Product (MVP), ChatGPT, Redis, Message Bus, CSV, WebSockets, Docker, AWS ECS Fargate, Spring Boot, Browser Automation, CI/CD Pipelines, ECS, GitLab, Redshift, Canvas, Generative Artificial Intelligence (GenAI), UI Components, Product Development, Data Architecture, RESTFul APIs, Site Speed Optimization, OWASP, UI Development, End-to-end Implementation (E2E), Epic, Healthcare, Performance Optimization, Back-end Architecture, JSON API, Cloud Platforms, Multi-tenant SaaS, Role-based Access Control (RBAC), Webhooks, Scalability, Web Scalability, Web UI Design, API Access Control, API Development, Cloud Architecture, Linux, API Backwards Compatibility, XML, Lighthouse, Third-party APIs, Cloudflare, JSON, Code Review, Security, Code Auditing, Server-side Programming, System Design, System Integration, Technical Architecture, Multi-tenant Architecture, SaaS, Scrum, Product Requirements Documentation (PRD), System Development Life Cycle (SDLC), Planning, Agile, DB, Spring, REST APIs, Documentation, Auditing

Staff Full-Stack Leader (Platform Optimization)

2021 - 2023

Delivery Hero

Designed, implemented, and maintained high-traffic back-end services handling over one million unique users daily across multiple brands and regions.
Developed a product from scratch that generates landing pages that are deployed in all continents and in more than 60 countries, using Gatsby, TypeScript, Cloudflare, Amazon S3, and more AWS services.
Improved CronJobs on a legacy service using Ruby, Rails, PostgreSQL, and Kubernetes to fine-tune database interactions and redesign some of the CronJobs to add more granularity to the execution, reducing database instances and costs by 50%.
Migrated two services (1,000 rpm) from a regional base to a country base without downtime. Implemented missing functionality, created new instances, migrated data, switched the API gateway, and imported delta data files.
Implemented AWS Lambda functions to replace the short URLs external providers widely used in the Delivery Hero ecosystem, saving over €1,000 per month. Used AWS Lambda, Node.js, Terraform, and Kong API Gateway.
Created a microservice to generate static landing pages, deprecating external providers, reducing over €5,000 in monthly costs, and improving the conversion rate by 60%. Used Spring Boot, Kotlin, React, Gatsby, Drone CI, Amazon S3, and Cloudflare.
Contributed to our load-test suite with several test scenarios where we tried to put our services under a lot of stress by simulating multiple requests growing exponentially, reaching our goal of handling 10x peak load, using Scala and Gatling.
Redesigned all landing pages for all the different brands of Delivery Hero across the globe in 60 countries. We achieved this by offering full customization in terms of design, images, colors, fields, language, etc.
Migrated legacy monolith logic to smaller services designed around domain boundaries, leveraging Event-Driven Architecture with SQS and SNS.
Integrated AWS RDS (PostgreSQL) and NoSQL (DynamoDB) stores with caching strategies via Redis and CloudFront (later migrated to Cloudflare).

Technologies: Ruby on Rails (RoR), Spring Boot, Kotlin, React, Node.js, Microservices, Kubernetes, Helm, Terraform, PostgreSQL, Gatsby, Drone CI, Amazon S3 (AWS S3), CSS, Software Engineering, Spinnaker, Redux-Saga, REST, Kong, TypeScript, REST APIs, Docker, Docker Compose, Front-end, Redux, Amazon Web Services (AWS), AWS Cloud Architecture, Architecture, Enterprise Application Architecture, Full-stack, Storybook, Bootstrap, JavaScript Testing, Figma, Webpack, Ruby, Rust, Shell, JavaScript, Scala, Gatling, Load Testing, Technical Leadership, Automation, HTML5, Containers, Containerization, Responsive Web Design (RWD), NPM, Leadership, Full-stack Development, SQL, AWS Lambda, HTML, CSS3, Next.js, Solution Architecture, Microservices Architecture, Front-end Architecture, API Integration, Web Development, User Experience (UX), User Interface (UI), Data Modeling, APIs, Dashboards, Analytics, Contentful, Headless CMS, Event-driven Architecture, Front-end Development, Single-page Applications (SPAs), Material UI, Amazon API Gateway, Distributed Systems, Large-scale Distributed Systems, Web Architecture, Back-end, DevOps, Deployment, Git, Distributed Architecture, MERN Stack, Content Management Systems (CMS), Databases, Query Optimization, API Design, GitHub, Amazon Simple Queue Service (SQS), Cloud Infrastructure, Software Design, Integration, GraphQL, GraphQL API, Back-end Development, UI Design, UX Design, Google, Seos, Agile Software Development, Minimum Viable Product (MVP), Vue, Redis, Message Bus, Startups, CSV, WebSockets, CI/CD Pipelines, ECS, Google Cloud Platform (GCP), UI Components, Product Development, A/B Testing, Database Migration, Infrastructure as Code (IaC), Sentry, Data Architecture, RESTFul APIs, Legacy Code, OWASP, UI Development, AI Integration, End-to-end Implementation (E2E), Twilio, Epic, SMS, Performance Optimization, Back-end Architecture, JSON API, Cloud Platforms, Multi-tenant SaaS, Role-based Access Control (RBAC), Webhooks, Scalability, Web Scalability, Web UI Design, API Access Control, API Development, Cloud Architecture, API Backwards Compatibility, SSH, Google Analytics, Zod, Lighthouse, React Testing Library, Serverless, Third-party APIs, System Architecture, Amazon Elastic Container Service (ECS), Cloudflare, JSON, Code Review, Security, Code Auditing, Server-side Programming, System Design, System Integration, Technical Architecture, General Data Protection Regulation (GDPR), Multi-tenant Architecture, SaaS, Authentication, Zapier, Scrum, Product Requirements Documentation (PRD), System Development Life Cycle (SDLC), Planning, Agile, DB, Spring, Documentation, Amazon DynamoDB, Hooks, Amazon Simple Notification Service (SNS), JSON Web Tokens (JWT)

Engineering Manager

2020 - 2021

Delivery Hero

Facilitated a work environment where my teams could share ideas and perform their best by promoting communication, removing roadblocks, listening to feedback on issues, and more.
Conducted weekly one-on-one meetings and guided and mentored my team to grow their soft and technical skills, which resulted in six promotions in the individual contributor career path and one in the managerial career path.
Defined hiring funnels for different positions in the logistics workforce. Achieving our ambitious hiring goals for six quarters in a row.

Technologies: Management, Software Engineering, TypeScript, REST APIs, Docker, Docker Compose, Front-end, Redux, Amazon Web Services (AWS), AWS Cloud Architecture, Architecture, Enterprise Application Architecture, Full-stack, Storybook, Bootstrap, JavaScript Testing, Figma, Cypress, Webpack, Technical Leadership, Responsive Web Design (RWD), Containers, Containerization, HTML5, NPM, JavaScript, Leadership, Full-stack Development, SQL, Ruby, AWS Lambda, HTML, CSS3, React, Solution Architecture, Microservices Architecture, Front-end Architecture, API Integration, Web Development, User Experience (UX), User Interface (UI), Data Modeling, APIs, Dashboards, Analytics, Contentful, Headless CMS, Front-end Development, Event-driven Architecture, Single-page Applications (SPAs), Material UI, Amazon API Gateway, Microservices, Distributed Systems, Large-scale Distributed Systems, Web Architecture, Back-end, DevOps, Deployment, Git, Distributed Architecture, MERN Stack, Content Management Systems (CMS), Databases, API Design, GitHub, Amazon Simple Queue Service (SQS), Cloud Infrastructure, Software Design, Back-end Development, UI Design, UX Design, Google, Seos, Agile Software Development, Minimum Viable Product (MVP), Redis, Message Bus, Startups, CSV, Ruby on Rails (RoR), Browser Automation, CI/CD Pipelines, ECS, Google Cloud Platform (GCP), UI Components, Product Development, A/B Testing, Database Migration, Infrastructure as Code (IaC), Sentry, Data Architecture, RESTFul APIs, Legacy Code, OWASP, UI Development, Twilio, Epic, SMS, Performance Optimization, Back-end Architecture, JSON API, Cloud Platforms, Multi-tenant SaaS, Role-based Access Control (RBAC), Webhooks, Scalability, Web Scalability, Web UI Design, API Access Control, API Development, Cloud Architecture, Lighthouse, Third-party APIs, Cloudflare, JSON, Server-side Programming, System Design, System Integration, Technical Architecture, General Data Protection Regulation (GDPR), Multi-tenant Architecture, Authentication, Zapier, Scrum, Product Requirements Documentation (PRD), System Development Life Cycle (SDLC), Planning, Agile, DB, Prisma, Spring, Documentation

Engineering Lead

2017 - 2020

Care.com

Split a monolithic application enhancing the first component of the recruitment process with an improvement of 50% in the loading time and 10% in the conversion rate, using React, Jest, and Puppeteer.
Created a component library used across different teams, reducing the development time and achieving a better look and feel on all parts of the application. Here we used React, Emotion, and Storybook.
Defined the scope of the project and implemented a new redesign, making sure that the whole team met our commitments on time, achieving close to 100% on-time delivery of all features assigned to the team.
Shared knowledge by giving different workshops on front-end technologies such as React, Redux, styled-components, and Puppeteer, and on back-end technologies such as Kotlin, CircleCI, and Docker Compose.
Conducted one-on-one weekly meetings and evaluated individual contributions.
Redesigned the onboarding funnel completely, also called new user registration, where we used a mobile-first approach and created a set of reusable components that later would improve the development speed of other teams.
Refactored complex backend microservices and data pipelines (Python/Django/Java), decomposing monolithic blocks into domain-driven services to maximize horizontal scalability.
Created feature toggles and AB testing infrastructure for back-end logic to support rapid experimentation on user behavior.
Optimized slow queries across MySQL and Oracle databases, significantly reducing average response times in critical flows.

Technologies: Spring Boot, Java, Groovy, Grails, React, Styled-components, Management, Software Engineering, Engineering Management, TypeScript, REST APIs, Docker, Front-end, Redux, Amazon Web Services (AWS), AWS Cloud Architecture, Architecture, Enterprise Application Architecture, Full-stack, Storybook, Bootstrap, JavaScript Testing, Technical Leadership, Responsive Web Design (RWD), Containers, Containerization, HTML5, NPM, JavaScript, Leadership, Full-stack Development, SQL, HTML, CSS3, Solution Architecture, Microservices Architecture, Front-end Architecture, API Integration, Web Development, User Experience (UX), User Interface (UI), Data Modeling, APIs, Dashboards, Analytics, Contentful, Headless CMS, Front-end Development, Event-driven Architecture, Single-page Applications (SPAs), Material UI, Microservices, Distributed Systems, Large-scale Distributed Systems, Web Architecture, Back-end, DevOps, Deployment, Git, Distributed Architecture, eCommerce, Content Management Systems (CMS), Databases, Query Optimization, API Design, GitHub, Amazon Simple Queue Service (SQS), Jenkins, Cloud Infrastructure, Software Design, Integration, Back-end Development, Google SEO, Search Engine Optimization (SEO), UI Design, UX Design, Google, Seos, Agile Software Development, Minimum Viable Product (MVP), Redis, Message Bus, Startups, CSV, Browser Automation, Puppeteer, CI/CD Pipelines, GitLab, UI Components, Product Development, A/B Testing, Sentry, Data Architecture, RESTFul APIs, Legacy Code, OWASP, UI Development, End-to-end Implementation (E2E), Epic, SMS, Performance Optimization, Back-end Architecture, JSON API, Cloud Platforms, Role-based Access Control (RBAC), Scalability, Web Scalability, Web UI Design, API Access Control, API Development, Cloud Architecture, API Backwards Compatibility, XML, SSH, Python, Google Analytics, Lighthouse, Third-party APIs, Django, JSON, Data Pipelines, Server-side Programming, System Design, System Integration, Technical Architecture, General Data Protection Regulation (GDPR), Multi-tenant Architecture, Scrum, Product Requirements Documentation (PRD), System Development Life Cycle (SDLC), Planning, Agile, DB, Spring, Documentation, Reporting

Senior Software Engineer

2015 - 2017

Oracle

Implemented a recommendation engine based on user activity that helped engineers and sales teams find relevant information more efficiently.
Developed an end-to-end testing framework with Selenium, Gradle, and Java 8 that considerably reduced the number of regression bugs.
Built a cross-platform mobile application prototype with the same capabilities as a desktop site, allowing engineers to manage all their tasks on their mobile devices. Using Ionic Framework, Angular, and Cordova.
Created a React application to request and deliver feedback on the quality and relevance of the articles in the knowledge database widely used by support and sales engineers.
Developed and maintained back-end services for Oracle’s internal recommendation engine in the Global Sales Engineering team using Java and PL/SQL, enhancing sales productivity.
Built cron-based batch jobs to sync data across systems and generate reports consumed by business intelligence teams.

Technologies: Java, React, Apex, Oracle, Oracle Database, REST, Selenium, Ionic, Angular, PL/SQL, Spring MVC, Apache Maven, Gradle, REST APIs, Full-stack, Bootstrap, Cordova, AngularJS, Responsive Web Design (RWD), HTML5, NPM, JavaScript, Full-stack Development, SQL, HTML, CSS3, Solution Architecture, Front-end Architecture, API Integration, Web Development, User Experience (UX), User Interface (UI), Data Modeling, APIs, Dashboards, Front-end Development, Single-page Applications (SPAs), Back-end, Git, Databases, Query Optimization, API Design, Jenkins, Software Design, Back-end Development, UI Design, UX Design, Agile Software Development, CSV, Database Migration, Data Architecture, RESTFul APIs, Legacy Code, UI Development, End-to-end Implementation (E2E), Performance Optimization, Back-end Architecture, JSON API, Role-based Access Control (RBAC), Vanilla JS, API Access Control, API Development, API Backwards Compatibility, XML, SSH, Python, Lighthouse, System Design, System Integration, Technical Architecture, Ajax, Scrum, System Development Life Cycle (SDLC), Planning, DB

Senior Java Developer | Technical Lead

2012 - 2015

Internet Brands

Implemented a feature to compare cars increasing daily visits from 1,000 to 10,000 users, using Vanilla JavaScript, HTML, CSS, and REST services.
Created an email campaign and templating engine that sends emails to users based on their interests in vehicles or articles on the site, fully compliant with all email clients and sites.
Collaborated and mentored a team from the USA, Uruguay, India, and Mexico in redesigning one of the top three sites of car sales in the USA.
Led the development of an email campaign backend engine in Java with Apache Velocity, generating personalized templates using user activity data and integrating it with MySQL.
Rebuilt legacy services as RESTful APIs to be consumed by frontend clients, improving performance and maintainability.

Technologies: Java, Groovy, Apache Velocity, CSS, HTML, Oracle Database, JavaScript, jQuery, Spring MVC, REST APIs, Front-end, Full-stack, Bootstrap, Full-stack Development, Technical Leadership, MySQL, Responsive Web Design (RWD), Leadership, SQL, CSS3, Solution Architecture, API Integration, Web Development, User Interface (UI), Data Modeling, Front-end Development, eCommerce, Databases, Query Optimization, Jenkins, Software Design, Agile Software Development, Cars, Startups, End-to-end Implementation (E2E), Back-end Architecture, JSON API, Vanilla JS, API Development, XML, SSH, System Integration, Technical Architecture, Ajax, Waterfall, DB, Reporting

Software Development Engineer

2010 - 2012

NIC Mexico

Completed search, registration, and management of domain names with the .mx country code top-level domain (ccTLD).
Created a parser to consume reports of payments from several bank institutions and register fulfilled transactions.
Trained members on front-end technologies and JavaServer Faces (JSF) framework.

Technologies: Java, JSF, JavaScript, CSS, HTML, Oracle Database, Full-stack, Full-stack Development, SQL, Web Development, User Interface (UI), Front-end Development, eCommerce, Databases, Query Optimization, End-to-end Implementation (E2E), Back-end Architecture, Vanilla JS, SSH, Waterfall, Reporting

Software Engineer Intern

2008 - 2010

The ITESM

Developed a site that showed the grade of the students on a specific test.
Implemented a registration application that tracked student assistance using a barcode.
Created an application for the teachers to upload and format data of students' grades.

Technologies: Java, Jakarta Server Pages (JSP), jQuery, JavaScript, PHP, Visual Basic, AccessData, HTML, Web Development, Waterfall

Software Engineer Intern

2008 - 2009

Messicom

Implemented a module to support multiple languages throughout the application, allowing users to translate into any language, when previously it was just English <> Spanish.
Developed a new CMS module to create static content as landing pages.
Simplified several modules of our custom CMS which helped with code maintainability and reduced bugs overall.

Technologies: PHP, CakePHP, JavaScript, jQuery, Linux, LAMP, Apache, MySQL, CSS, HTML, Web Development, Waterfall

Experience

Minimalist Personal Website

http://grekz.com

I created an extremely minimalist website in less than a day using Gatsby, React, TypeScript, Cloudflare, Amazon S3, and pnpm. I had been postponing the creation of a portfolio site and one that could contain all the places where people can contact me. I finally managed to do a quick proof of concept, and this is the result.

Care.com: Landing Page and Registration of New Users

A React, Redux, and styled-components application that was split from a monolithic service. We improved the front-end stack, introducing React and Redux for user enrolment and to the whole European branch of the company, reducing load time by 50% and improving the completion rate by 10%. I was involved in this project's plan, design, implementation, and delivery phases.

Delivery Hero: Static Landing Page Creator

Dodo is a static landing page creator developed to replace the existing WordPress solution. On the back end, we used Kotlin, Spring Boot, and PostgreSQL, while on the front end, we used React and Gatsby. To generate and publish the pages, we used Drone CI. I participated on both sides of the application development process. The Rider Food Panda is an example of a page developed with Dodo.

Gartner.com: Migration of Private Social Network to Next.js 14

A React Native for Web social network for top-level executives, created by one of the biggest IT firms in the world.

I was involved in the full-stack migration from React Native for Web to Next.js 14. We improved loading time from 20s to under 1s, increased traffic by +300%, and reduced the time to market for new features from two hours to under five minutes.

The platform runs on AWS, using AWS S3 to store assets, AWS ECS Fargate to run the container of the application, GitHub Actions as a CI/CD tool, React and TypeScript for the front end, Next.js as a framework, MongoDB as a database, Go as a back-end API, and AWS CDK as infra as code.

Delivery Hero: Hiring Platform

The hiring platform designed for Delivery Hero, a leading global food delivery company with operations in over 70 countries, has successfully streamlined and optimized recruitment processes for both the company and job seekers.

Leveraging technologies such as AWS, Cloudflare, React, Kotlin, Ruby on Rails, and PostgreSQL, this platform offered a user-friendly interface, powerful search capabilities, robust reporting and analytics tools, mobile responsiveness, enhanced candidate experience, scalability to accommodate diverse company needs, ongoing support and maintenance, and robust security measures.

As a result of this innovative solution, Delivery Hero has received millions of applicants across all continents, significantly reducing time-to-hire, increasing applicant quality, and improving overall recruitment efficiency, ultimately leading to a more productive and successful workforce.

Oracle: Global Sales Engineering Platform

A global sales engineering management platform for Oracle, enabling efficient scheduling, meeting preparation, knowledge sharing, and product presentation support for sales teams across the organization.

This innovative solution was instrumental in fostering a more effective and collaborative working environment. The platform allowed us to customize our meetings based on the needs of each team, ensuring that every meeting was tailored to its specific audience and purpose. Moreover, it facilitated seamless knowledge sharing across different Oracle products, providing support for product presentations and promoting comprehensive understanding among sales teams.

Education

2005 - 2009

Bachelor's Degree in Computer Science

Instituto Tecnológico y de Estudios Superiores de Monterrey (ITESM) - Monterrey, Mexico

Certifications

MAY 2020 - PRESENT

Computer Vision Expert | Nanodegree Program

Udacity

APRIL 2020 - PRESENT

Reactive Architecture: Domain Driven Design - Level 2

Lightbend

APRIL 2020 - PRESENT

Course Artificial Intelligence Foundations: Neural Networks

LinkedIn Learning

APRIL 2020 - PRESENT

Reactive Architecture: Reactive Microservices - Level 2

Lightbend

APRIL 2020 - PRESENT

Reactive Architecture: Introduction to Reactive Systems - Level 2

Lightbend

APRIL 2020 - PRESENT

AI Programming with Python | Nanodegree Program

Udacity

JANUARY 2020 - JANUARY 2023

AWS Certified Solutions Architect Associate

AWS

Skills

Libraries/APIs

Node.js, React, REST APIs, JSON API, API Development, Claude API, jQuery, Chart.js, Puppeteer, Zod, React Testing Library, Redux-Saga, Playwright, GraphQL API, Vue

Tools

JavaScript Testing, GitHub, Git, Claude, Kong, Docker Compose, Google Analytics, Figma, Amazon Elastic Container Service (ECS), Amazon Simple Queue Service (SQS), Seos, ChatGPT, GitLab, Canvas, Sentry, Claude Code, Astro, Lighthouse, GitHub Copilot, Prisma, Amazon Simple Notification Service (SNS), Helm, Terraform, Flyway, Apache Maven, Gradle, Webpack, NPM, CircleCI, Bitbucket, Shell, Amazon Elastic Container Registry (ECR), Amazon CloudFront CDN, AWS Command Line Interface (CLI), Gatling, Apache, Amazon EKS, AWS Fargate, AWS Cloud Development Kit (CDK), Amazon CloudFront, Jenkins, Turbo, Zapier, Drizzle ORM

Languages

Java, CSS, HTML, JavaScript, TypeScript, SQL, HTML5, Kotlin, Python, Go, Ruby, CSS3, XML, Groovy, Apex, Rust, Scala, PHP, Visual Basic, GraphQL

Frameworks

Ruby on Rails (RoR), Bootstrap, Next.js, Vanilla JS, JSON Web Tokens (JWT), Spring Boot, Redux, Cypress, Tailwind CSS, Material UI, Spring, Grails, Selenium, Ionic, Angular, Spring MVC, Apache Velocity, JSF, Jest, CakePHP, AngularJS, Jakarta Server Pages (JSP), Swagger, Svelte, NestJS, Django, Express.js, Flutter

Paradigms

REST, Enterprise Application Architecture, Responsive Web Design (RWD), Microservices Architecture, Web Architecture, DevOps, Agile Software Development, Back-end Architecture, Role-based Access Control (RBAC), API Access Control, Scrum, Microservices, Management, Event-driven Architecture, Search Engine Optimization (SEO), Web UI Design, Server-side Programming, Agile, E2E Testing, Load Testing, Automation, UI Design, UX Design

Platforms

Docker, Amazon Web Services (AWS), Contentful, Web, Kubernetes, Oracle, Linux, AWS Lambda, Vercel, Google Cloud Platform (GCP), Drone CI, Spinnaker, Oracle Database, LAMP, AccessData, Apache Kafka, Azure, Twilio

Storage

PostgreSQL, Databases, Database Migration, JSON, DB, Amazon S3 (AWS S3), PL/SQL, MongoDB, MySQL, Redis, JSON-LD, Data Pipelines, Amazon DynamoDB, Oracle Database Tuning, NoSQL, MarkLogic, Redshift, Elasticsearch

Industry Expertise

System Development Life Cycle (SDLC), Healthcare

Other

Software Engineering, Programming, Software Architecture, Front-end, AWS Certified Solution Architect, AWS Cloud Architecture, Architecture, Full-stack, Storybook, CI/CD Pipelines, Technical Leadership, Full-stack Development, Leadership, APIs, Solution Architecture, Front-end Architecture, API Integration, Web Development, User Experience (UX), User Interface (UI), Data Modeling, Dashboards, Headless CMS, Front-end Development, Single-page Applications (SPAs), Distributed Systems, Large-scale Distributed Systems, Back-end, Deployment, Distributed Architecture, Content Management Systems (CMS), Query Optimization, API Design, Software Design, Back-end Development, Minimum Viable Product (MVP), UI Components, Data Architecture, RESTFul APIs, Site Speed Optimization, UI Development, End-to-end Implementation (E2E), Epic, AI-assisted Development, Performance Optimization, Cloud Platforms, Multi-tenant SaaS, Scalability, Web Scalability, Cloud Architecture, Third-party APIs, Software Development, System Architecture, Code Review, System Design, System Integration, Technical Architecture, Multi-tenant Architecture, SaaS, Vibe Coding, Artificial Intelligence (AI), Cloudflare, Containers, Amazon RDS, Supabase, Analytics, Charts, Amazon API Gateway, MERN Stack, eCommerce, Cloud Infrastructure, Integration, Google SEO, Google, AI Agents, Large Language Models (LLMs), Message Bus, Startups, CSV, Browser Automation, ECS, AI Tools, Product Development, A/B Testing, Sitemaps, Legacy Code, OWASP, AI Integration, SMS, Agentic Engineering, AI-generated Code, Webhooks, API Backwards Compatibility, SSH, Agentic AI, LLM Integration, Serverless, Security, Code Auditing, Ajax, Agentic Coding, General Data Protection Regulation (GDPR), Authentication, Waterfall, Product Requirements Documentation (PRD), Planning, Documentation, Auditing, Reporting, Anthropic, Hooks, Gatsby, Computer Vision, AI Programming, Neural Networks, API Gateways, Styled-components, Engineering Management, PNPM, Cordova, DocumentDB, Containerization, ESLint, GitHub Actions, Debugging, Cloud, OpenTelemetry, SvelteKit, Cars, Crypto, WebSockets, AWS ECS Fargate, Generative Artificial Intelligence (GenAI), Infrastructure as Code (IaC), Component Libraries, Turborepo, Cursor AI, Fintech, Supabase Auth

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