compilla.tech

Guilherme Cruz

Full Stack Developer · .NET + React

I build systems that cannot go down. At work, insurance APIs in microservices. Outside it, four products of my own in production, from the database schema to the server.

Five years in, from a front-end internship to the insurance systems running in production now.

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Work

My products, live

All of them are my own: idea, code, infrastructure and release.

  • Investing

    InvestFolio

    Portfolio management for long-term investors. You enter how much you are putting in, and it tells you how much goes into each asset to pull the real portfolio back toward its target allocation.

    Clean Architecture backend, installable PWA frontend.

    • .NET 10
    • React
    • PostgreSQL
    • PWA

    investfolio.compilla.tech

  • Weddings

    MyWeddingList

    A wedding gift registry you share as a link. Guests pay by PIX or card and the money lands straight in the couple’s account, with no store in the middle and no steep commission.

    Image uploads and a real payment checkout.

    • Next.js
    • .NET
    • PIX
    • Payments

    myweddinglist.compilla.tech

  • Mobile app

    StudyApp

    A gamified study app: Pomodoro, spaced-repetition flashcards (SM-2), tasks and notes in a single flow, plus a virtual plant that grows as you study.

    Android, shipped with its own backend.

    • React Native
    • Expo
    • .NET 10
    • PostgreSQL

    studyappsunflower.com

  • Tool

    Stardew Planner

    Drop in your Stardew Valley save and it tells you what the Community Center still needs, and what you can still finish this season.

    No server, no database: the save never leaves the player’s machine.

    • React
    • TypeScript
    • In the browser

    stardewplanner.compilla.tech

Approach

I solve the places where the layers meet

Most of the friction in a project lives at the boundaries: between the frontend and the API, between the API and the database, between code that passes on your machine and code that stays standing on a server at three in the morning. Working across all four layers forced me to solve those boundaries instead of passing them to the next person.

In practice that means architecture that survives a change of mind, tests where the business rules are hard, and a deploy that is a single command, because a manual deploy is a deploy nobody runs.

  • Live product, not a prototype

    I hand over something running on its own domain, with HTTPS and an automated deploy. Not a repository for someone else to publish later.

  • Decisions written down

    Every non-obvious choice is documented with its reasoning. Whoever picks the project up next does not have to guess why it looks the way it does.

  • Privacy by default

    I only store data the product actually needs. In Stardew Planner that became the architecture: there is no server to leak anything.

Experience

Where I have worked

Five years, from a front-end internship to the insurance systems in production today.

  1. Junto Seguros

    Sep 2025 to now

    Software Engineer

    Critical systems for surety and rental-guarantee insurance. Microservice APIs in .NET and Node.js, breaking legacy endpoints into smaller services, and external integrations kept asynchronous so the main path never waits on a third party. Observability through logs, metrics and traces.

    • .NET
    • Node.js
    • Docker
    • Kubernetes
    • Datadog

  2. CIEE/PR

    May 2022 to Sep 2025, 3 years 5 months

    Mid-level Full Stack Developer

    REST APIs in .NET Core and web portals, with a legacy ASP.NET Web Forms system living alongside the new code. Clean Architecture and SOLID, query modelling and tuning in SQL Server, deploy automation and front-end tests.

    • .NET Core
    • Angular
    • SQL Server
    • CI/CD

  3. WEIPA

    Jul 2021 to Mar 2022

    Full Stack Developer, internship

    A production management system that went into a client’s industrial process. C# on the backend, GraphQL for queries, Angular on the interface and PostgreSQL underneath.

    • C#
    • GraphQL
    • Angular
    • PostgreSQL

  4. Mirum Agency

    Jun 2019 to Nov 2020

    Front-end, internship

    Maintaining client systems in JavaScript for the agency, and building marketing emails.

    • JavaScript
    • CodeIgniter

Stack

What I use every day

Tools are a means. These are the ones I know well enough to estimate against with confidence.

Backend

  • .NET 10
  • C#
  • Node.js
  • Minimal APIs
  • GraphQL
  • Microservices
  • Clean Architecture
  • xUnit

Frontend

  • React 19
  • TypeScript
  • Next.js
  • Angular
  • Astro
  • Vite
  • TanStack Query

Mobile

  • React Native
  • Expo
  • Google Play

Data & infrastructure

  • PostgreSQL
  • SQL Server
  • EF Core
  • Docker
  • Kubernetes
  • Linux
  • nginx
  • CI/CD
  • Datadog

Contact

Where to find me

If any of this caught your attention, or you want to talk about building something, either of these works.