Available to hire
Hi, I’m James Mangubat, a seasoned .NET Software Engineer specializing in building scalable, multi-tenant SaaS platforms using Domain-Driven Design and Clean Architecture. My main expertise lies in back-end development with ASP.NET Core, but I’m also versatile in frontend technologies like ReactJS and modern JavaScript frameworks. I enjoy collaborating with cross-functional teams, mentoring junior developers, and managing full software development lifecycles.
I have extensive experience delivering CRM and enterprise systems that enhance billing, customer management, and operational efficiency. I’m passionate about writing clean, scalable code and continuously improving performance and developer productivity. Let’s build something great together!
Language
English
Fluent
Work Experience
FreelancerSelf
January 1, 2024 - April 30, 2025Delivered responsive company website for LadonCo with mobile-first UI. Designed full SaaS infrastructure for TintTrack CRM, including Azure CI/CD, CDN, and secure tenant deployment. Led a team of 3 frontend engineers, increasing development velocity by 30% through clear UI architecture, shared component libraries, and streamlined review workflows. Refactored .NET 8 libraries for .NET 9 readiness, improving performance benchmarks by 15–20%. Provided DevOps support for DNS, Plesk, and mail server configuration.
C# .NET Core / .NET 8 Developer at Book That In Ltd
November 1, 2023 - March 31, 2024Upgraded backend to .NET 8, improving code clarity and developer efficiency. Integrated Aprimo DAM to streamline content workflows and governance. Automated asset handling with Aprimo APIs, reducing manual tasks.
Full-Stack .NET 6 Developer at DumpTruckDispatcher.com
October 1, 2022 - November 30, 2023Extensively utilized AspNetZero Boilerplate to accelerate development of new features and improve code maintainability and modularity. Led reporting project with ActiveReports, enhancing client data insights.
Web Developer at HSO Enterprise Solutions
May 1, 2021 - September 30, 2022Integrated data sources via SSIS, enhancing CRM data flow and reporting accuracy. Customized Dynamics 365 with Power Platform and plugins to automate workflows and handle complex business logic. Built tailored CRM modules, streamlining customer data processes and boosting team efficiency. Implemented Power Automate, Logic Apps, and Power BI to enable real-time insights and reduce manual operations.
Assistant Software Architect / Full-Stack Developer at ProcQ LLC
July 1, 2020 - April 30, 2021Developed and benchmarked multiple Azure SQL integration strategies, directly contributing to a 40% improvement in API runtime and data access efficiency by informing team decisions on optimal implementation. Designed system integrations and documented design strategies, improving system performance and reliability of web API; Drafted technical docs and guided design reviews.
ASP.NET MVC Developer at Zylocon Ltd
June 1, 2019 - July 31, 2020Built C# ASP.NET web and Windows desktop applications for Zylocon's flagship SaaS product, supporting growth in market share among construction material suppliers. Enhanced product versatility and UX through desktop services integration.
Senior .NET Developer at Business Net Solutions Ltd
August 1, 2016 - June 30, 2019Developed transport scheduler, reducing logistics costs. Migrated legacy CRM and maintained cross-functional modules. Sample projects included ReactJS UI and jQuery UI integration.
Education
Bachelor of Science at AMA Computer College
June 1, 1995 - March 31, 2000Qualifications
Microsoft Certified Technologist – SQL Server 2005
January 1, 2005 - December 31, 2005Microsoft Great Plains – Fundamentals, Customizations, and Programming
January 11, 2030 - June 12, 2025Classic ASP.NET – Web Application Development
January 11, 2030 - June 12, 2025Quality Management and Leadership Training
January 11, 2030 - June 12, 2025Financial Accounting: Fundamentals of Accounts Management & GL Troubleshooting
January 11, 2030 - June 12, 2025Leadership and Personal Transformation Seminar
January 11, 2030 - June 12, 2025Quality Management Training & Seminar
January 11, 2030 - June 12, 2025Aprimo DAM Administration Training
January 11, 2030 - June 12, 2025Industry Experience
Software & Internet, Professional Services, Retail, Transportation & Logistics, Real Estate & Construction, Financial Services
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