Secure Software Engineer

Hi, I'm Chester.

I build secure software that people can actually rely on.

I build web apps, APIs, and internal systems with security in mind from the start. Most of my work is full stack, but I care most about the parts that usually get messy: auth, data flow, validation, permissions, and whether the product still feels simple to use when all of that is in place.

View Projects Contact Me

Selected Work

Projects that show how I build and where I spend my attention.

AI Pitaka

AI-assisted budgeting with voice-first expense capture.

AI Pitaka started from a simple frustration: logging expenses is annoying, so most people stop doing it. I built it to make that part feel lighter. You can speak naturally, let the app interpret the expense, and update your balances without typing everything out by hand.

These screens cover the main loop: checking balances, logging expenses, and keeping the budget in view.

Role

I built the whole thing myself, from product decisions to implementation.

Stack

TanStack-based web app with offline-first behavior.

Technical Focus

JWT auth, input validation, sync that does not fall apart easily, and a mobile-first interface.

Hard Problem

Making voice input useful enough that people do not have to fight the app after every expense.

Impact

It is the budgeting app I use myself now, and people around me actually keep coming back to it.

Link

Visit live project

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CarPool Connect

A carpool coordination app shaped by real commuting costs.

CarPool Connect came from a practical problem. Fuel keeps getting more expensive, and commuting gets worse when everyone has to solve that alone. I built it as a mobile-first app to make shared rides easier to organize and less awkward to manage.

Role: I handled the frontend, backend, and product direction.
Stack: Angular, .NET Web API, and MSSQL.
Security: JWT auth, input validation, booking protection, and ownership checks on the API side.
Hard Problem: Figuring out trip matching and seat management without making the flow annoying to use.
Status: Still in progress. I am focusing on getting the main workflow right before I release it.

Government Use

CASE FILE / HRIS-GOV-08

Screens withheld because this was built for a government organization.

Government HRIS

An internal system built for complexity, accountability, and scale.

This government HRIS pulled personnel workflows into one internal system for a public-sector organization. It was not just a bunch of CRUD screens. The hard part was keeping roles, approvals, records, and accountability clear while the system stayed usable for the people depending on it every day.

Role: Team Lead, with hands-on work in backend, frontend, and DevOps.
Client Context: Government organization with sensitive personnel workflows and restricted system visuals.
Team: 8-person delivery team.
Stack: .NET Web API, Blazor WebAssembly Standalone, and MSSQL.
Security: Role-based access control, audit logs, defensive validation, and secure API design.
Challenge: Keeping the workflows clear, the access boundaries strict, and the codebase maintainable at the same time.

Core Strengths

This is the kind of work I want to keep doing.

Secure Full-Stack Delivery

I can take a product from idea to deployed system without treating security like something to bolt on later.

Backend and API Architecture

I care about clean data flow, service boundaries that make sense, and backend decisions that still hold up when the product grows.

Practical Application Security

I pay attention to auth, validation, ownership checks, audit trails, and the kinds of mistakes or abuse that real systems actually run into.

Product-Minded Engineering

I do not like building features that only look good in demos. I want the workflow to make sense and feel reliable when people use it for real work.

Background

The short version.

Education

Batangas State University NEU

BS Information Technology, Business Analytics

2021-2025 | Magna Cum Laude

Certifications

CompTIA Tech+
Linux Professional Institute: Web Development Essentials

Profiles