ES

Manta, Ecuador

Full Stack Developer

Welinton Guerrero

I build web platforms that serve several companies from one codebase. 3+ years on betting products, e-commerce and internal tools.

Core stack

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

Stack and technologies

Frontend

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

Backend and databases

  • Node.js
  • Python
  • PHP
  • MongoDB
  • PostgreSQL
  • MySQL

Testing and quality

  • Vitest
  • Testing Library
  • Chromatic

DevOps and tools

  • Docker
  • GitHub Actions
  • DigitalOcean
  • Seq

Experience

  1. July 2023 to now

    Manta, Ecuador. On-site.

    ZGames Technology

    Full Stack Developer

    ZGames builds technology for the betting industry.

    • 75% less time to build a new module
    • 90% fewer inline styles
    • +50K registered users on the platform
    • Own the frontend architecture of the public portal and the components the team reuses.
    • Help set the architectural standards, review code and keep technical debt from piling up.
    • Integrate casino and sportsbook providers, and test the money flows before certification.
    • Write backend services in Node.js and TypeScript, with MongoDB queries for reports, user management, bets, transactions and settings.
    • Add structured logs in Seq to the services and follow how the flows behave in production.
    • Angular
    • TypeScript
    • RxJS
    • NgRx
    • Signals
    • Node.js
    • MongoDB
    • PostgreSQL
    • Seq

    See the platform

  2. October 2025 to now

    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.
    • Automated the inventory sync and the bulk catalogue updates.
    • Maintain the system and take on requests as they come up.
    • PHP
    • JavaScript
    • Python
    • MySQL

    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.

    • Planned the contents of the course across the term.
    • 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 betting portal interface (placeholder image)

One codebase, every brand

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

Products in the platform

  • Sorti365

    Public betting portal. Sorti365 is the client, and the same portal ships to other operators with different tokens.

  • ZGames BackOffice

    Administration for the betting portal. Built once and reused across clients.

  • SortiCenter

    Internal management for the Sorti365 operation.

Results

  • One codebase ships to several operators, each with its own brand.
  • Casino and sportsbook integrations tested against real money flows before certification.
  • Back office and internal management built alongside the public portal.

Stack

  • Angular
  • TypeScript
  • RxJS
  • NgRx
  • Signals
  • CSS
  • Node.js
  • MongoDB
  • Design Tokens
Visit site

Freelance Production, e-commerce 2025 to now

Tecnored Ecuador e-commerce interface (placeholder image)

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
  • SQL Server
  • Google Sheets API
Visit site

Master thesis, UNIR Design system 2026

Component library documentation catalogue (placeholder image)

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
  • CSS
  • Storybook
  • Vitest
  • Testing Library
  • Chromatic
  • GitHub Actions
Visit site Public repository

Engineering thesis, ULEAM Internal platform 2024

Laboratory booking system interface (placeholder image)

Another database, the same rules

Solution
Node.js and TypeScript backend 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

Personal project In development, fintech 2026 to now

Clear Fund savings management interface (placeholder image)

Every balance can be explained

Problem
A balance nobody can trace back to the movement that produced it cannot be audited. By the time someone notices, the history is already gone.
Solution
Every balance change comes from a cash movement. There are no manual adjustments and nothing is ever deleted, so corrections are reversals that point back at what they correct. I wrote all 25 features as specifications before writing code, and recorded each architectural decision as a numbered ADR.
Role
Sole developer. Specifications, architecture, implementation and CI.

Results

  • 14 numbered ADRs, each with its context, decision and consequences.
  • 5 of 25 features complete, with every status kept in a traceability matrix.
  • Integration tests run on a real PostgreSQL, because audit immutability is a database trigger no mock can observe.

Stack

  • Next.js
  • React
  • TypeScript
  • PostgreSQL
  • Prisma
  • Zod
  • Vitest
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 B1, 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 am an Information Technology Engineer working as a 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