ES

Manta, Ecuador

Full Stack Developer

Welinton Guerrero

I build multi-tenant web platforms that give each operator its own brand from one codebase. 3+ years on iGaming products, e-commerce and internal tools.

Core stack

  • Angular
  • TypeScript
  • Node.js
  • MongoDB
  • Vitest
  • Docker
View work Get in touch Download CV

Stack and technologies

Frontend

  • Angular
  • TypeScript
  • RxJS
  • NgRx
  • Signals
  • React
  • Storybook

Backend

  • Node.js
  • Spring Boot
  • Java
  • Python
  • PHP

Databases

  • PostgreSQL
  • MongoDB
  • MySQL
  • Redis

Testing and DevOps

  • Vitest
  • Testing Library
  • Docker
  • GitHub Actions
  • Seq
  • DigitalOcean

Experience

  1. July 2023 to now

    Manta, Ecuador. On-site.

    ZGames Technology

    Full Stack Developer (Mid-Level)

    ZGames builds technology for the iGaming industry.

    • Lead the Angular frontend architecture of the multi-tenant iGaming public portal with design token theming, supporting 50,000+ registered player accounts on its primary operator.
    • Structured the base component system and design token governance, mentoring the technical team through code reviews (PRs) and accelerating the full backoffice migration (~12 modules) in 1 month.
    • Design and integrate APIs and services with external providers in Java (Spring Boot) and Node.js, validating transactional consistency and financial reconciliation prior to operator certification.
    • Design backend services and REST APIs in Node.js and TypeScript with Redis caching and MongoDB, optimizing transactional reports and user management.
    • Implemented structured observability with Seq for transactional failure correlation, provider downtime alerts, and critical 24/7 endpoint traceability.
    • Angular
    • TypeScript
    • RxJS
    • NgRx
    • Signals
    • Node.js
    • Spring Boot
    • Java
    • MongoDB
    • PostgreSQL
    • Redis
    • Seq

    See the platform

  2. October 2025 to August 2026

    Manta, Ecuador. Remote, on demand.

    Tecnored Ecuador

    Freelance Full Stack Developer

    Tecnored sells technology equipment through an online store.

    • Built the online store and its admin panel with PHP and JavaScript.
    • Designed a Python ETL pipeline syncing ~5,800 products in batches of 500 records every ~13 minutes from SQL Server to MySQL without disrupting the legacy system.
    • Kept the store running in production and took on the changes the client asked for.
    • PHP
    • JavaScript
    • Python
    • MySQL
    • Google Sheets API

    See the store

  3. May 2023 to June 2023

    Manta, Ecuador. On-site.

    Empresa Pública Aguas de Manta

    Web Development Intern

    Aguas de Manta runs the drinking water and sanitation for the city.

    • Added authentication with OpenID Connect.
    • Integrated Mapbox so the app could show geographic data.
    • OpenID Connect
    • Mapbox

  4. October 2022 to January 2023

    Manta, Ecuador. On-site.

    Universidad Laica Eloy Alfaro de Manabí

    Teaching Assistant, Mobile Applications

    The public university in Manta, where I took the engineering degree.

    • Prepared and delivered classes on mobile development with Flutter and React Native, and wrote the supporting material.
    • Reviewed the code students submitted and gave them feedback on it.
    • Flutter
    • React Native

Selected work

ZGames Technology Production, iGaming 2023 to now

Sorti365 iGaming portal: live match odds above a grid of games

One codebase, every brand

Problem
The brief was an iGaming platform for one operator. Partway through we saw it could serve other operators too. Forking the code per client would have made it impossible to maintain.
Solution
I structured the Angular frontend and its base components so the entire look changes by swapping design tokens. On the backend I wrote the REST APIs and services for users, reports, transactions and account configuration.
Role
Full Stack Developer on the team that built it from scratch. Frontend architecture, backend REST APIs, provider integrations.

Products in the platform

  • Sorti365

    Public iGaming portal. Sorti365 is the client, and the same portal can ship to other operators with different tokens.

  • ZGames BackOffice

    Administration for the iGaming portal. Built once, to be reused across operators.

  • SortiCenter

    Internal management for the Sorti365 operation.

Results

  • One codebase that gives a separate brand per operator, instead of a fork per client.
  • Sportsbook and casino integrations tested against real money flows before certification by the operator.
  • Back office and internal management built alongside the public portal.

Stack

  • Angular
  • TypeScript
  • RxJS
  • NgRx
  • Signals
  • Node.js
  • Spring Boot
  • Java
  • MongoDB
  • PostgreSQL
  • Redis
  • Seq
Visit site

Freelance Production, e-commerce 2025 to 2026

Tecnored storefront home page with its product promotion banner

New store, untouched legacy

Problem
Their stock lived in an old SQL Server that nobody could touch, and the catalogue was updated by hand.
Solution
I wrote a Python ETL that copies the stock into MySQL without touching the old system. The store and the panel run on PHP and JavaScript, and a bulk import module pulls products from Google Sheets.
Role
Freelance Full Stack Developer. ETL, backend, storefront, admin design.

Results

  • The old system keeps running exactly as it did before.
  • Prices and offers get updated from a spreadsheet instead of one by one.
  • Admin panel designed from scratch for categories, brands, galleries and offers.

Stack

  • PHP
  • JavaScript
  • Python
  • MySQL
  • Google Sheets API
Visit site

Master thesis, UNIR Design system 2026

Storybook canvas showing a games carousel component, the component tree and the controls panel

The public version of a private system

Solution
Angular library built with the Presentational-Container pattern and Atomic Design. The tokens hold colours, typography and spacing for the whole system.

Results

  • Unit tests with Vitest and visual regression with Chromatic.
  • Component catalogue in Storybook, releases automated with GitHub Actions.

Stack

  • Angular
  • Signals
  • TypeScript
  • Storybook
  • Vitest
  • Testing Library
  • GitHub Actions
Visit site Public repository

Engineering thesis, ULEAM Internal platform 2024

Screenshot in progress

Another database, the same rules

Solution
REST API and backend in Node.js and TypeScript with Clean Architecture. The frontend is an Angular SPA organised by features, with NgRx holding the state.

Results

  • Four user roles, each with its own permissions.
  • Deployed on DigitalOcean with Docker, Docker Compose and Nginx.

Stack

  • Angular
  • NgRx
  • Node.js
  • TypeScript
  • Docker
  • DigitalOcean
Public repository

Education

Degrees

  • Master in Web User Interface Design and Development

    Universidad Internacional de La Rioja (UNIR)

    February 2025 to May 2026 · Spain, remote

  • Engineering degree in Information Technology

    Universidad Laica Eloy Alfaro de Manabí

    April 2019 to August 2024 · Ecuador, on-site

Certification

  • Continuing Education Certificate in Leadership

    MIU City University Miami

    Conscious leadership, emotional intelligence, assertive communication and relationship management at work.

    Credential ID 0b05d46a-8af5-4fd6-a7ed-53c593a84c31

    Verify this certificate

Languages

  • Spanish Native
  • English B2, upper-intermediate

About

Angular is my strongest area, but I rarely stay on one side of the product.

I was going to study accounting until someone told me computing was not for everyone, and I took it personally. Writing my first programs in PSeInt, Java and Visual Basic I found out an idea could turn into something that runs, and that curiosity took me to the engineering degree and later to the master in web interface design.

Today I work as a Software Engineer and Full Stack Developer. Some days are for building an interface and others for deciding how data moves between services, plugging in an external API, or fixing something in the backend that the user ends up feeling anyway.

I get into the technical decisions on the product and not only the part assigned to me, though a good share of the work is not technical at all. Answering support when something breaks in production, or sitting in a meeting to agree on what comes next, is building the product too.

Get in touch

Timezone GMT-5, no daylight saving.

Download CV (EN)

Elsewhere