The latest articles on DEV Community by HERNAN RICARDO AVILA CASTILLO (@hernan_ricardo). https://dev.to/hernan_ricardo https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F3753951%2F9699d4f7-a0ad-41fd-a683-bfdbb8becf44.jpg https://dev.to/hernan_ricardo en HERNAN RICARDO AVILA CASTILLO Thu, 05 Feb 2026 02:49:58 +0000 https://dev.to/hernan_ricardo/building-a-treasury-saas-with-react-nodejs-firebase-mysql-4ogj https://dev.to/hernan_ricardo/building-a-treasury-saas-with-react-nodejs-firebase-mysql-4ogj <h1> Building a Treasury SaaS with React, Node.js, Firebase &amp; MySQL </h1> <h3> Applying 25+ Years of Software Experience to a Modern Financial </h3> <p>Platform</p> <p>Hello DEV community,</p> <p>My name is <strong>Hernán Ricardo Ávila Castillo</strong>, a senior fullstack developer with more than <strong>25 years of experience</strong>, currently based in <strong>Guatemala</strong>. I am also completing my degree in <strong>Computer Science and Systems Engineering</strong>.</p> <p>At the moment, my main focus is the development of a <strong>Treasury Management SaaS platform</strong>: a modern system designed to support real-world financial operations, payment workflows, balances, and business controls.</p> <p>In this post, I would like to share what I am building, why I selected this technology stack, and how I approach architecture when working on a fintech-oriented product.</p> <h2> The Project: A Treasury / ERP Ecosystem </h2> <p>The platform is being designed to support:</p> <ul> <li>Treasury operations </li> <li>Cash flow monitoring </li> <li>Accounts payable and receivable </li> <li>Payment approval workflows </li> <li>Financial tracking across projects and organizations </li> <li>A scalable SaaS foundation for future ERP modules </li> </ul> <p>This is not a demo project. The goal is to evolve it into a <strong>production-grade enterprise platform</strong>.</p> <h2> Technology Stack </h2> <p>After working with many technologies throughout my career, I decided to build this treasury system using a modern and reliable stack:</p> <h3> Frontend: React </h3> <p>React provides an excellent foundation for:</p> <ul> <li>Admin dashboards </li> <li>Component-driven interfaces </li> <li>Long-term scalability in UI development </li> </ul> <h3> Backend: Node.js </h3> <p>Node.js enables:</p> <ul> <li>Fast API development </li> <li>Strong integration capabilities </li> <li>Clean service-oriented architecture </li> </ul> <h3> Authentication and Platform Services: Firebase </h3> <p>Firebase is used for:</p> <ul> <li>Secure authentication </li> <li>Notifications </li> <li>Realtime capabilities when needed </li> <li>Simplified scalability for SaaS workflows </li> </ul> <h3> Core Financial Database: MySQL </h3> <p>MySQL remains a strong choice for treasury data because it provides:</p> <ul> <li>Relational consistency </li> <li>Transactional reliability </li> <li>Strong reporting and structured modeling </li> </ul> <h2> High-Level Architecture </h2> <p>The platform follows a modular SaaS architecture:<br> </p> <div class="highlight js-code-highlight"> <pre class="highlight plaintext"><code>React Admin Dashboard | v Node.js REST API Layer | +-------------------+ | | Firebase Auth MySQL Database | | Notifications Treasury Ledger + ERP Data </code></pre> </div> <p>This separation allows:</p> <ul> <li>Clear API boundaries </li> <li>Enterprise-grade data integrity </li> <li>Independent scaling of modules </li> </ul> <h2> Key Design Principles </h2> <p>After more than two decades building software, several principles remain constant:</p> <h3> 1. Financial systems require strong consistency </h3> <p>Treasury platforms must be <strong>auditable, traceable, and transaction-safe</strong>.<br><br> Data integrity is not optional.</p> <h3> 2. SaaS requires modular thinking </h3> <p>Every module must evolve independently:</p> <ul> <li>Payments </li> <li>Clients </li> <li>Projects </li> <li>Approvals </li> <li>Reporting </li> </ul> <h3> 3. Automation is part of the future </h3> <p>The platform is being developed with automation in mind, integrating AI-driven workflows using tools such as <strong>n8n</strong> and <strong>Make</strong>.</p> <p>Treasury is not only accounting. It is operations.</p> <h2> What I Am Building Next </h2> <p>Upcoming milestones include:</p> <ul> <li>Multi-tenant SaaS structure </li> <li>Role-based access control </li> <li>Payment gateway integrations </li> <li>Approval pipelines </li> <li>Financial reporting dashboards </li> <li>Cloud-native deployment workflows </li> </ul> <h2> Why I’m Sharing This Here </h2> <p>I am joining DEV.to to:</p> <ul> <li>Share real-world software engineering experience </li> <li>Learn from the community </li> <li>Document the evolution of this treasury platform </li> <li>Connect with others building fintech and enterprise systems </li> </ul> <h2> Final Thoughts </h2> <p>Even after decades in software, building systems like this remains exciting. Technology evolves constantly, and so do we as engineers.</p> <p>If you are working on treasury platforms, ERP systems, fintech SaaS products, or React/Node architectures, I would be glad to connect and exchange ideas.</p> <p>Thank you for reading.</p> <h2> Links </h2> <ul> <li>GitHub: <a href="https://github.com/hricardoavilac" rel="noopener noreferrer">https://github.com/hricardoavilac</a> </li> <li>Website: <a href="https://racastillo.com" rel="noopener noreferrer">https://racastillo.com</a> </li> </ul> <p>#dev #react #node #firebase #mysql #saas #fintech #softwarearchitecture</p> node react saas showdev