Brian Díaz, Developer in Santiago, Dominican Republic
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Brian Díaz

Verified Expert  in Engineering

Bio

Brian is an innovative developer and a problem solver. He has 8+ years of experience developing web back- and front-end services in various domains and with diverse tech stacks for startups and medium and large companies. Experienced in working with fast-moving teams and fixed deadlines, Brian is proficient in different methodologies and technologies, allowing him to learn and quickly adapt to new working environments.

Portfolio

Zetta, LLC.
JavaScript, CSS, Python, React.js, Node.js, Full-stack, SSO Engineering...
Veracode Inc.
Node.js, OWASP, REST API, Express.js, MongoDB, SQLite, JSON Web Tokens (JWT)...
TheoremOne
React.js, JavaScript, TypeScript, Node.js, Cloud Engineering, Azure Design...

Experience

Availability

Part-time

Preferred Environment

Slack, MacOS, Linux

The most amazing...

...project I've joined as one of the 1st engineers was involved in creating one of the top automotive startups in Brazil, which raised more than $55 million.

Work Experience

Senior Full-stack Software Engineer

2024 - PRESENT
Zetta, LLC.
  • Led the architecture and development of a scalable minimum viable product (MVP) in a fast-paced startup environment, ensuring the platform met early-stage business needs and allowed for iterative improvements.
  • Developed a user management system supporting role-based access control (RBAC), empowering administrators and team owners to invite users, assign roles, and manage permissions.
  • Integrated automated billing using Stripe, creating a system that supported both flat-rate and per-user fees, as well as volume-based pricing for data analytics services.
  • Implemented a chat assistant using @nlux/react and @nlux/langchain-react, enabling interactive and automated user support within the platform.
  • Defined database schema to support user roles, permissions, teams, settings, and dashboard visibility, ensuring secure and efficient access to data for B2B clients.
Technologies: JavaScript, CSS, Python, React.js, Node.js, Full-stack, SSO Engineering, Cloud Engineering, Tailwind UI, Tailwind CSS, TypeScript, Next.js, Vercel, Stripe Development, Stripe Development, PostgreSQL, Tableau Development, Prisma, Docker, Minimum Viable Product (MVP), LangChain, Front-end, SQL

Senior Software Engineer | Content Creator

2023 - 2024
Veracode Inc.
  • Created Node.js Express Rest APIs for OWASP API Security Top 10 Course.
  • Implemented security measures outlined in the OWASP API Security Top 10 guidelines. Implemented JWT, Rate Limiters, XSS, and SQL injection security measures, among others.
  • Impressed the client with the efficiency with which these functional APIs were developed, recognizing their potential impact on the broader software engineering community.
Technologies: Node.js, OWASP, REST API, Express.js, MongoDB, SQLite, JSON Web Tokens (JWT), System Security, System Security, Security, JavaScript

Software Engineer

2022 - 2023
TheoremOne
  • Worked as a full-stack engineer, collaborating with clients in the US to deliver high-quality solutions.
  • Developed new features, resolved bugs, and provided ongoing maintenance for a calendar application used by a prominent TV show company in the US. Technologies utilized include React, Node.js, JavaScript, Firebase, Jest, and CircleCI.
  • Designed and implemented a secure service for sharing 3D printing resources for a medium-sized client in the US. Technologies employed include Node.js, TypeScript, NestJS, Google Cloud Platform (GCP), and JSON Web Tokens (JWT).
  • Played a vital role in the Houston team, creating a minimum viable product (MVP) for ClarityFirst, a large US-based company. Developed the application using React, TypeScript, React Query, MUI (Material UI), React Testing Library, and Lexical.
  • Led the front-end development for a major dental industry client, creating and implementing solutions using React, TypeScript, Material UI, Storybook, and React Query while transforming Figma designs into functional, responsive features.
Technologies: React.js, JavaScript, TypeScript, Node.js, Cloud Engineering, Azure Design, Material UI, Material Design, Figma, Firebase, Jest, Storybook, React Query, REST API, NestJS, UI Development, ECMAScript 6, Styled-components, React.js, CSS, CSS3, jQuery, UI Development, Front-end, SQL

Senior Full-stack Engineer

2022 - 2023
Potion AI, Inc
  • Developed new features for the AI platform using React, TypeScript, Node.js, NestJS, and GraphQL.
  • Converted Figma designs into working responsive features.
  • Fixed bugs on the back end using Node.js, NestJS, TypeScript, and GraphQL.
  • Improved the search performance by 30% by refactoring queries.
Technologies: React.js, Node.js, Full-stack, JavaScript, SQL, Python, GraphQL, Slack Development, MacOS, Chakra UI, REST API, Storybook, Unit Testing, Software Engineering, HTML5, ECMAScript 6, UI Development, UI Development, Front-end

Senior Front-end Engineer

2022 - 2022
OzoneAI, Inc.
  • Fixed bugs in the current platform using the Ruby on Rails framework.
  • Helped the team fix and deploy a failing application in staging and production to AWS using AWS Elastic Beanstalk, Redis, Amazon RDS, Amazon CloudFront, and Amazon EC2.
  • Added new features using React and JavaScript alongside Rails.
Technologies: JavaScript, TypeScript, React.js, Ruby on Rails, AWS, PostgreSQL, AWS Elastic Beanstalk, Redis, Slack Development, MacOS, REST API, Storybook, Unit Testing, Software Engineering, HTML5, ECMAScript 6, UI Development, Front-end, SQL

Software Engineer

2021 - 2022
eBay
  • Took part of the team of engineers that developed the certified refurbished admin tool as a front-end engineer, using Node.js, Express.js, React, Redux, TypeScript, JavaScript, and CSS.
  • Implemented unit tests with Jest, Enzyme, and Cypress, code coverage with Jest, and used Prettier with ESLint for code linting.
  • Maintained, added features, and fixed bugs on pages that have millions of daily views in collaboration with multiple teams.
  • Created micro frontends POCs with Webpack Module Federation and Next.js to implement in future eBay projects.
  • Implemented eBay's middleware packages for session handling and API calls in a Node.js server that runs concurrently with the front end.
  • Worked with the Venus team in implementing new components to the listing page, which has millions of views daily.
  • Collaborated with the MyEbay team in migrating legacy systems to a new architecture and redesigning my eBay pages using Marko.js, Node.js, and JavaScript.
Technologies: Node.js, JavaScript, React.js, Marko.js, Git, React.js, Jest, TypeScript, Express.js, ESLint, Webpack, CSS, HTML, Enzyme, Jira, Scrum Master Consulting, GitHub, Responsive Web Development, Agile Development, SQL, Next.js, Front-end, Web Development, Slack Development, MacOS, NPM, Unit Testing, Software Engineering, HTML5, ECMAScript 6, UI Development

Software Engineer

2020 - 2021
Levvel
  • Worked with a large team on the migration of a FoxPro system from a big company to a top-notch tech stack.
  • Used React, TypeScript, Redux, Sagas, Redux Observables, Less, Webpack, and Material UI in the front end.
  • Built REST APIs to handle the Node.js-based back end with NestJS, TypeScript, SQL Server, Redis, and TypeORM.
  • Created scripts that generate schema views from SQL Server into TypeORM entities.
  • Assigned as temporary tech lead for four months with an average of 92% sprint completion rate.
Technologies: Node.js, TypeScript, NestJS, React.js, Redux, Learner Style Sheets, CSS, SQL Server 2015, Redis, AWS RDS, Material UI, JSON Web Tokens (JWT), ESLint, Jest, Enzyme, Webpack, TypeORM, Bitbucket, PostgreSQL, Redux-Saga, HTML, Jira, Scrum Master Consulting, Git, Responsive Web Development, Agile Development, SQL, Full-stack, jQuery, APIs, Front-end, Back-end Developers, Web Development, AWS, Slack Development, MacOS, Linux, Figma, Amazon S3, REST API, Styled-components, Storybook, NPM, Unit Testing, Software Engineering, HTML5, ECMAScript 6, UI Development, UI Development

Software Engineer

2015 - 2021
Instacarro
  • Started as one of the first engineers in the company that evolved into one of the major startups in Brazil and Latin America with more than $55 million raised.
  • Led the software development of numerous services and REST APIs for real-time geolocation, reporting, and mailing using Node.js, JavaScript, and TypeScript.
  • Created serverless functions for event handling with the auction platform, mailing, and financial solutions, among others.
  • Worked with notification systems using pusher, AWS Lambda, and Firebase.
  • Implemented several AWS features to manage services in the cloud, such as RDS, EC2, ECS, S3, CodePipeline, Lambda, Cognito, SES, SNS, CloudFront, and others.
Technologies: HTML, CSS, Node.js, MongoDB, TypeScript, React.js, JavaScript, AWS Lambda, NestJS, Koa, Express.js, Twilio Development, Google Calendar API, AWS Elastic Beanstalk, AWS, AWS, AWS RDS, Git, Bitbucket, React.js, Firebase, Enzyme, JSON Web Tokens (JWT), Learner Style Sheets, PostgreSQL, Redux, Redis, NoSQL, MySQL, Jira, Scrum Master Consulting, YouTube API, Responsive Web Development, Agile Development, Bootstrap, SQL, Full-stack, APIs, Front-end, Back-end Developers, Web Development, AWS, Serverless, Twilio Development, Startup Development, Slack Development, Linux, Figma, AWS, Amazon S3, REST API, WebSockets, Material UI, Styled-components, NPM, Unit Testing, Software Engineering, HTML5, ECMAScript 6, UI Development, UI Development

Full-stack Developer

2018 - 2018
Kambda
  • Worked with US clients using the Ruby on Rails framework.
  • Developed new functionalities for fintech and healthcare portals.
  • Fixed issues and migrated the legacy Rails app to newer versions.
Technologies: Ruby, Ruby on Rails, JavaScript, jQuery, HTML, CSS, Redis, PostgreSQL, RSpec, Ruby on Rails, Slack Development, Linux, Heroku, REST API, Unit Testing, Software Engineering, HTML5, ECMAScript 6, UI Development, Front-end, SQL

Reporting Tool for Delta Dental

Led the front-end development of interactive business analytics using React, TypeScript, and React Query. Brought Figma designs to life by creating UI components with Material UI, making sure they look great on all screen sizes and devices.

I implemented flexible integration, robust authentication, powerful reporting, data privacy, and custom branding. I integrated Bold BI reports to enhance IBA's reporting capabilities. The application was hosted securely on AWS for scalability.

Also, I documented the project and laid the groundwork for future enhancements.

Calendar App for ITV

Added new features, fixed bugs, and maintained and refactored the Calendar App for a large TV-show company in the US using React, Node.js, JavaScript, Firebase, Jest, and CircleCI. This project included a undo and redo cache implemented with Redux and and HTML to PDF rendering tool.

Laser GG Sharing Service

https://www.laser.gg/
Created a secure REST API to share 3D printing resources for a medium client in the US using Node.js, TypeScript, NestJS, GCP, and JWT. The service has been successfully used every day by thousands of users.
2010 - 2015

Bachelor's Degree in Computer Systems Engineering

Pontifical Catholic University Mother and Teacher - Santiago, Dominican Republic

MAY 2023 - PRESENT

Introduction to OpenAI API & ChatGPT API for Developers

Udemy

APRIL 2020 - PRESENT

NestJS Zero to Hero - Modern TypeScript Back-end Development

Udemy

Libraries/APIs

Node.js, React.js, REST API, React.js, Twilio Development, Redux-Saga, YouTube API, Google Calendar API, Marko.js, jQuery, React Query, React Testing Library, Stripe Development, Stripe Development

Tools

Slack Development, Git, GitHub, Bitbucket, Jira, Figma, AWS, NPM, AWS, AWS, React.js, Webpack, CircleCI, RSpec, Tableau Development, Prisma

Languages

JavaScript, HTML, HTML5, ECMAScript 6, TypeScript, SQL, CSS, Learner Style Sheets, Ruby, Python, GraphQL, CSS3

Paradigms

Unit Testing, Agile Development, Scrum Master Consulting, Design Patterns

Frameworks

NestJS, Redux, Bootstrap, Koa, Express.js, JSON Web Tokens (JWT), Material UI, Jest, Next.js, Ruby on Rails, Ruby on Rails, Tailwind CSS

Platforms

MacOS, Linux, Firebase, Heroku, AWS, Twilio Development, Cloud Engineering, AWS Lambda, AWS Elastic Beanstalk, Vercel, Azure Design, Docker

Storage

MongoDB, PostgreSQL, NoSQL, MySQL, Amazon S3, Redis, SQLite, System Security

Other

Software Engineering, Web Development, Full-stack, APIs, Front-end, Back-end Developers, UI Development, Material Design, TypeORM, Enzyme, Responsive Web Development, Serverless, Startup Development, WebSockets, Styled-components, Storybook, UI Development, AWS RDS, ESLint, Software Design, Computer Science, Algorithms, SQL Server 2015, Google Cloud Functions, Chakra UI, OpenAI GPT-3 API, GPT-4, BI Reporting, OWASP, System Security, Security, Full-stack, SSO Engineering, Tailwind UI, Minimum Viable Product (MVP), LangChain

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