Julio is available for hire
Hire JulioJulio Szabo
Verified Expert in Engineering
ASP.NET Developer
Córdoba, Cordoba, Argentina
Toptal member since March 12, 2013
Bio
Julio is a senior software engineer specializing in Microsoft .NET with extensive experience building web applications across diverse business domains. He is adaptable, responsible, and effective, working both independently and in teams. With over 13 years of experience delivering high-quality solutions through Toptal, he focuses on continuous personal and professional growth, providing reliable and scalable results.
Portfolio
Gensler - Main
Microsoft SQL Server, CSS, HTML
Kaplan
C#, .NET, Full-stack, Git, CI/CD Pipelines, Angular, Azure, MySQL Server...
ContractPodAi
.NET, ASP.NET Web Forms, Microsoft Visual Studio, ASP.NET...
Experience
- ASP.NET - 12 years
- SQL - 12 years
- JavaScript - 10 years
- C# - 10 years
- LINQ - 8 years
- NHibernate - 7 years
- ASP.NET MVC 3 - 5 years
- ASP.NET Web API - 3 years
Work Experience
ASP Developer
2025 - 2025
Gensler - Main
- Maintained and enhanced a legacy ASP application hosted on AWS EC2, resolving critical bugs and improving overall stability for active client operations.
- Diagnosed and fixed long-standing issues in classic ASP modules, reducing application errors by improving stored procedures and back-end logic.
- Optimized several SQL Server stored procedures, improving data retrieval performance and reducing query execution time across key workflows.
- Refactored outdated components in the legacy system, improving maintainability and enabling smoother future enhancements.
- Improved UI reliability by updating HTML and CSS fragments, ensuring consistent rendering across modern browsers in the Windows ecosystem.
- Collaborated closely with cross-functional teams using Git, Jira, and Confluence to streamline development workflow and documentation.
- Implemented debugging strategies that increased issue-resolution speed, enabling the team to meet project deadlines consistently.
- Leveraged experience working with clients such as JP Morgan, Bank of America, Pinterest, ADP, Jefferson, Santander, and Truist to deliver enterprise-grade solutions.
Technologies: Microsoft SQL Server, CSS, HTML
Full-stack Developer
2021 - 2023
Kaplan
- Worked on multiplatform applications based on microservices built on .NET Framework with SQL and NoSQL databases in a distributed team worldwide.
- Worked on a financial system, adding new functionalities and fixing issues related to credits/debits and payments for small and big accounts.
- Improved and adapted existing microservice of shipping and tax calculations for external orders.
- Worked on a web application for order processing and product selling, adding new functionalities and fixing issues.
Technologies: C#, .NET, Full-stack, Git, CI/CD Pipelines, Angular, Azure, MySQL Server, Jenkins, Web API, ASP.NET Web Forms, Microservices, Jira, Salesforce Sales Cloud, Agile Sprints, Scrum, Entity Framework, RabbitMQ, Swagger, AutoMapper, Integration Testing, Unit Testing, Microsoft Visual Studio, SQL, SQL Server Management Studio (SSMS), Transact-SQL (T-SQL), LINQ, ASP.NET MVC 3, Bootstrap, ASP.NET Web API, GitHub, AngularJS, HTML5, Microsoft SQL Server, REST APIs, CSS3, Object-oriented Programming (OOP), Model View Controller (MVC), Postman
.NET Engineer
2021 - 2021
ContractPodAi
- Developed new functionalities in the users' module on an existing application.
- Worked on the existing platform, adding new functionalities and fixing existing issues.
- Worked on email assignments for user functionality.
Technologies: .NET, ASP.NET Web Forms, Microsoft Visual Studio, ASP.NET, SQL Server Management Studio (SSMS), Transact-SQL (T-SQL), LINQ, NHibernate, ASP.NET MVC 3, Bootstrap, GitHub, HTML5, Microsoft SQL Server, CSS3, Object-oriented Programming (OOP), Model View Controller (MVC)
Full-stack C# Developer
2020 - 2021
Gwentaa, LLC
- Converted proptotypes from InVision to real screens in Blazor, a .NET front-end web framework.
- Built a Blazor application from design with Telerik controls.
- Added unit test modules for background processes in a .NET app.
Technologies: C#, Visual Studio, JSON, ASP.NET Web Forms, REST APIs, Blazor
Senior Full-stack Developer
2020 - 2020
BenefitEd
- Redesigned an existing application and added a new feature allowing companies multiple programs. Added new pages and a model and table to manage new entities in the application.
- Worked on a vast database migration script to support multiple programs' new features. The database used the SQL server stored in AWS.
- Worked on adapting the existing enrollment process for employees to the new model with multiple programs. The front-end app was developed in Angular 2.
Technologies: Amazon Web Services (AWS), Scrum, Agile, Git, jQuery, Web API, REST, Backbone.js, Angular, C#, ADO.NET, Microsoft Visual Studio, SQL Server Management Studio (SSMS), Transact-SQL (T-SQL), LINQ, ASP.NET MVC 3, ASP.NET Web API, HTML5, Microsoft SQL Server, REST APIs, CSS3, Object-oriented Programming (OOP), Model View Controller (MVC)
Back-end Software Engineer
2017 - 2020
VMBC - Emerios
- Built a service layer to process big data information and a PDF process generator.
- Built a 3rd-party validation process for new clients in the energy industry.
- Implemented PostGIS to handle geolocation functionality for street agents.
- Worked on new order creation via a REST API integrated with partners' APIs and applying custom rules.
- Imported a big data spreadsheet to SQL and PostgreSQL for new leads.
- Integrated with Lexis Nexis to make customer validations.
- Implemented new features for the API to manage customers' business logic for a multi-tenant application, fixed issues, and updated behaviors.
- Worked with a multi-tenant database with the SQL server row-level security and wrote long and complex stored procedures.
Technologies: Angular, NHibernate, Web API, C#, Microsoft Visual Studio, SQL, ASP.NET, SQL Server Management Studio (SSMS), Transact-SQL (T-SQL), LINQ, ASP.NET MVC 3, Bootstrap, ASP.NET Web API, GitHub, PostgreSQL, AngularJS, HTML5, Microsoft SQL Server, REST APIs, CSS3, Object-oriented Programming (OOP), Model View Controller (MVC), Postman
Full-stack Developer
2017 - 2017
Raamp, LLC
- Developed new features for a web application dedicated to providing assistance and organization for companies and property owners who want to rent them.
- Implemented a complete change history module for the web app.
- Worked with complex financial calculations, like checks, payments, bills, or credit.
Technologies: Active Server Pages (ASP), Azure, Microsoft SQL Server, JavaScript, ASP.NET MVC, Microsoft Visual Studio, SQL, SQL Server Management Studio (SSMS), Transact-SQL (T-SQL), LINQ, ASP.NET MVC 3, Bootstrap, ASP.NET Web API, AngularJS, HTML5, CSS3, Object-oriented Programming (OOP), Model View Controller (MVC), Postman, FontAwesome, Azure Blobs, TFS, MySQL
Full-stack Developer
2017 - 2017
Syntactical Solutions, LLC
- Developed new features for an existing web application.
- Migrated the app from old ASP pages MVC Razor Views.
- Worked on the existing platform and fixed bad behaviors.
- Implemented full logic to upload large files, splitting them into 1 MB parts.
Technologies: Active Server Pages (ASP), Azure, Microsoft SQL Server, JavaScript, ASP.NET MVC, Microsoft Visual Studio, SQL, ASP.NET, SQL Server Management Studio (SSMS), Transact-SQL (T-SQL), LINQ, ASP.NET MVC 3, Bootstrap, ASP.NET Web API, CSS3, Object-oriented Programming (OOP), Model View Controller (MVC), Infragistics, FontAwesome, Azure Blobs, TFS, MySQL
Full-stack Developer
2016 - 2017
Exxon Mobil
- Implemented a complete UI design with Bootstrap and jQuery.
- Built a web app that gets the user and machine name from the server side.
- Worked on a simple application solution for a proof of concept (POC).
Technologies: JavaScript, Microsoft SQL Server, C#, Microsoft Visual Studio, Transact-SQL (T-SQL), ASP.NET MVC 3, Bootstrap, CSS3, Object-oriented Programming (OOP), FontAwesome
Web Developer
2016 - 2016
Reservation Outdoors
- Made new functionality for the app built in ASP.NET MVC with Razor and AngularJS.
- Fixed bugs of existing functionality in the legacy application.
- Designed and implemented new features for the existing application.
Technologies: JavaScript, Microsoft SQL Server, C#, Microsoft Visual Studio, Transact-SQL (T-SQL), ASP.NET MVC 3, CSS3, Object-oriented Programming (OOP)
Full-stack Developer
2014 - 2016
RSI
- Fixed bugs in the legacy application built with web forms.
- Started building a new app in MVC with Razor as a view engine using the existing DB.
- Created new service components for a new app to replace the old logic in the old app.
- Implemented a blog inside the IIS site using WordPress running with PHP.
- Changed and redesigned big and complex report pages using jQuery and Bootstrap.
- Implemented jqGrid and changed all grids in the app.
Technologies: PHP, Microsoft SQL Server, JavaScript, C#, Microsoft Visual Studio, SQL, Transact-SQL (T-SQL), LINQ, ASP.NET MVC 3, CSS3, Object-oriented Programming (OOP), Model View Controller (MVC)
Full-stack Developer
2015 - 2015
nimblesoft
- Worked on a base project in ASP.NET MVC, adding new functionality and fixing bugs.
- Designed and implemented unit and integration tests with nUnit.
- Implemented new features on existing legacy applications built in ASP.NET MVC.
Technologies: Microsoft SQL Server, JavaScript, C#, Microsoft Visual Studio, SQL, Transact-SQL (T-SQL), LINQ, ASP.NET MVC 3, Bootstrap, CSS3, Object-oriented Programming (OOP)
Technical Leader | .NET Developer
2010 - 2015
Globant
- Developed a web app by migrating from an outdated previous version. Currently under construction in the testing and debugging stage.
- Used SQL Server for a web app database engine, NHibernate, and Fluent to manage object-oriented data.
- Developed a web app UI with MVC 3.0 and Razor pages, as well as jQuery and Ajax callbacks for interactions to optimize performance.
- Led a team of more than 15 engineers and five QA engineers.
- Liaised with clients and business analysts, relaying specifications to developers and delivering time estimates.
- Developed a set of internal and external references using jQuery popups for the web app UI.
- Implemented a general interface to perform app-wide searching for entities.
- Performed daily deploys on an internal server for quality control.
- Developed an application for a large insurance company to provide insurance quotes online.
- Implemented internal security architecture to control access to the insurance company's site using Microsoft Authorization Manager (Azman).
Technologies: Microsoft Team Foundation Server, CSS, Ajax, jQuery, JavaScript, XML, FluentNHibernate, NHibernate, PostSharp, .NET, Spring, Web MVC, C#, Microsoft Visual Studio, SQL, SQL Server Management Studio (SSMS), Transact-SQL (T-SQL), LINQ, ASP.NET MVC 3, ASP.NET Web API, CSS3, Object-oriented Programming (OOP), Infragistics, Model View Presenter (MVP), Aspect-oriented Programming, TFS, jqGrid, MySQL, Reflection, Functional Programming
.NET Full-stack Developer
2014 - 2014
Stacked Sports
- Developed a social media oversight platform that enables one admin across many users to view the posts of multiple other users.
- Integrated the application with Twitter, Facebook, and Instagram APIs to get users' tweets to find words configured in the app.
- Fixed bugs in the UI and back-end side of a legacy application.
Technologies: Instagram API, Facebook API, X (formerly Twitter) API, Microsoft SQL Server, JavaScript, C#, Microsoft Visual Studio, SQL, Transact-SQL (T-SQL), Object-oriented Programming (OOP)
.NET Full-stack Developer
2014 - 2014
General Genetics Corp
- Provided design, layout, and code updates to an eCommerce website.
- Developed payment methods form for an existing Application.
- Handled web deployments for an old Application in IIS.
- Fixed bugs on the UI and back end for a legacy application.
- Implemented the entire blog inside an IIS site running on PHP with Joomla and another one with WordPress.
Technologies: CSS, HTML, JavaScript, VB.NET, Visual Basic .NET (VB.NET), WordPress, Joomla 3
Senior Developer
2013 - 2014
Confidential Client (via Toptal)
- Maintained an application. Developed new features.
- Created and designed an MVC API containing all the back-end logic to integrate with the new UI for new app screens.
- Created and designed views in the database with loan calculations to integrate with NetTiers model objects.
- Analyzed all back-end logic for loan creation and designed and wrote a document.
Technologies: Scrum, JSON, jQuery, C#, ASP.NET, Transact-SQL (T-SQL)
Technical Leader | .NET Developer
2004 - 2010
CTL
- Developed a business rules engine with distributed architecture, separating each component with three-tier architecture.
- Created a website to manage user profiles and implemented extra applications to automate processes. Utilized a repository of DLLs.
- Constructed a solution for quality control to manage versioning of documents and findings.
- Involved in the implementation of the application for various customers in Cordoba.
- Built code generators to access stored procedures and components as a technical leader, speeding up the development of applications mounted on the business rules engine.
- Participated actively in the design and development of process automation with an external tool based on Windows Workflow Foundation.
- Worked with office automation with Excel report generation and automatic editing of Word files for a document versioning tool.
Technologies: XSLT, XML, JavaScript, Ajax, Microsoft 365, Microsoft SQL Server, C#, VB.NET, Visual Basic .NET (VB.NET), Visual Basic, Oracle, Microsoft Enterprise Library, Infragistics, Aspect-oriented Programming, TFS, XML/XSLT, InstallShield
Project History
Change History Management for Aspect Application
We used Aspect to interpret changes in the properties of the data model, which allowed us to save changes in the relevant database quickly. To do this in the data model, each class property must be marked with a particular attribute as a parameter that indicates the type of change to be recorded. Then, the Aspect was intercepted at compile time, and an extra behavior was added to each property class to record the changes.
Personal Blog
http://julioszabo.wordpress.com/I have created a personal blog on a third-party application to show some of my experience in development industries in which I have been working for more than 20 years. I have always worked with Microsoft technologies.
Technical Leadership at Globant
https://www.bsigroup.com/en-GB/our-services/entropy-governance-compliance-risk-grc-software/I have led a development team for a UK-based company, creating and developing a quality control application to manage their documentation processes. This project involved development tasks and designing and testing the application with product owners who approved or rejected changes and features.
Education
2014 - 2014
Master Degree in Javascript
https://www.codeschool.com/users/julioszabo - Online
1997 - 2009
Engineering Degree in Information Systems
National Technological University - Cordoba, Argentina
2007 - 2007
Project Manager with PMI Methodologies Degree in Management
Scarpatti & Asociados - Cordoba, Argentina
Skills
Libraries/APIs
Entity Framework, REST APIs, LINQ, jQuery, Infragistics, FluentNHibernate, X (formerly Twitter) API, Facebook API, Instagram API, Web API, Backbone.js, Microsoft Enterprise Library, AutoMapper
Tools
Postman, Microsoft Visual Studio, GitHub, Jira, jqGrid, TFS, Claude Code, Claude, PostSharp, Microsoft Team Foundation Server, Visual Studio, Git, InstallShield, Jenkins, Salesforce Sales Cloud, RabbitMQ
Languages
Visual Basic .NET (VB.NET), CSS3, SQL, CSS, C#, Transact-SQL (T-SQL), JavaScript, Active Server Pages (ASP), XML/XSLT, HTML5, Visual Basic, HTML, VB.NET, XML, XSLT, PHP
Frameworks
ASP.NET MVC, ASP.NET Web API, .NET, ASP.NET MVC 3, Bootstrap, ADO.NET, NHibernate, ASP.NET, Angular, AngularJS, Spring, Razor Pages, ASP.NET Web Forms, Swagger, Blazor
Paradigms
Agile Software Development, Object-oriented Programming (OOP), Model View Presenter (MVP), Model View Controller (MVC), Functional Programming, Scrum, Aspect-oriented Programming, REST, Agile, Microservices, Unit Testing
Platforms
Windows, Azure, Joomla 3, Amazon Web Services (AWS), WordPress, Oracle
Storage
SQL Server Management Studio (SSMS), JSON, MySQL, PostgreSQL, Azure Blobs, Microsoft SQL Server, MySQL Server
Other
Microsoft 365, FontAwesome, Reflection, Ajax, Web MVC, Full-stack, CI/CD Pipelines, Agile Sprints, Integration Testing, Data Modeling
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