Pablo Alessio, Developer in Poznań, Poland
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Pablo Alessio

Verified Expert  in Engineering

Software Architect and Full-stack Developer

Poznań, Poland
Toptal Member Since
February 26, 2016

Pablo is a software architect and full-stack developer specializing in Microsoft technologies and is certified as an Azure solutions architect expert. He delivers scalable and secure enterprise architecture, ultimate back-end and web development, and resilient cloud computing setups. He has completed 50 projects over 15 years, from implementing extraordinary large-scale apps to optimizing cloud computer costs. Pablo is ready to apply his skills to take a challenging project to the next level.


Various Clients
.NET, Architecture, Blazor, React, DevOps, Azure, Amazon Web Services (AWS)...
.NET, Azure, DevOps, SQL, Redis, APIs, ASP.NET Razor, Blazor, SignalR, NoSQL...
Various Clients
.NET, SQL, APIs, Windows Communication Foundation (WCF)...




Preferred Environment

.NET, C#, Architecture, Full-stack Development, APIs, Azure, SQL, NoSQL, DevOps, Web Development

The most amazing...

...thing I've built is an American fintech solution's main architecture, covering card spending, saving, investing, trading, sending money, and donating.

Work Experience

Senior Software Architect

2023 - 2024
Various Clients
  • Redesigned the existing app's architecture and cloud strategy for a simulation learning company, resulting in an evolution of the user experience and allowing business scalability.
  • Doubled the speed performance of the apps, reduced Azure cloud costs by 40%, and implemented monitoring tools to prevent bugs in advance.
  • Resolved long-standing structural issues that other engineers were not able to resolve.
  • Stabilized a platform with recurrent critical bugs by bringing user-reported issues and downtime to almost zero.
  • Transformed on-premise legacy processes into modern Azure PaaS for a cosmetic enterprise, using state-of-the-art computing, network, security, storage, and monitoring solutions.
  • Implemented technologies that the enterprise business was not aware of, and they emerged as the solution to revamp the internal processes.
  • Provided an architecture consultancy with insights and recommendations to scale up an existing AI product's technologies and best practices.
  • Designed the initial MVP, including the back-end and front-end SPA, security, and cloud strategy, using ultimate best practices such as vertical slice, clean architecture, domain-driven design, and event-driven architecture.
Technologies: .NET, Architecture, Blazor, React, DevOps, Azure, Amazon Web Services (AWS), Security, Monitoring, Redux, Lambda Architecture, Microsoft Power Automate, OpenAI GPT-3 API, OpenAI GPT-4 API

Senior Software Architect

2018 - 2023
  • Designed and documented the organization-wide software architecture for a top American fintech startup.
  • Sorted out the development team's technical approach with extensive guidelines that include best practices, principles, patterns, and code conventions.
  • Built complex banking and financial products, including features such as trading, custom portfolio models, rebalancing, savings, spending with cards, and donating.
  • Integrated the solution successfully with market-leading 3rd-party financial tools, including Stripe, Plaid, Apex, Dosh, IEX Cloud, Orbis, and Q2.
  • Reorganized the cloud infrastructure with Azure, which reduced costs by 60% and substantially increased security by implementing networking, encryption, and authorization layers.
  • Refactored a poorly designed solution into a new scalable system, transitioning from a monolithic solution into microservices.
Technologies: .NET, Azure, DevOps, SQL, Redis, APIs, ASP.NET Razor, Blazor, SignalR, NoSQL, Azure DevOps, Azure Service Bus, Confluence, Lucidchart, Visio, Architecture, Angular, CI/CD Pipelines, Azure DevOps Services, Cloud Architecture, Security

Senior Software Engineer | Architect

2016 - 2018
Various Clients
  • Improved customer experience substantially after completing an email marketing platform's ambitious architectural design optimization, allowing it to scale up.
  • Enhanced the corporate infrastructure of a building modeling platform and its internal systems.
  • Helped a global footwear design leader with their current eCommerce system, invoice generation, and aging of non-processed orders.
Technologies: .NET, SQL, APIs, Windows Communication Foundation (WCF), Windows Presentation Foundation (WPF), ASP.NET MVC, ASP.NET Razor, Bootstrap, Angular, TypeScript, jQuery, Enterprise Service Bus (ESB), RabbitMQ, Architecture, Windows Services, gRPC, Azure, CI/CD Pipelines, DevOps

Senior Software Engineer

2016 - 2017
Santander Bank
  • Served in the Nordic division of a top global consumer bank, dedicated to high-end loan apps.
  • Built from scratch an AML workflow tool for comprehensive anti-money laundering surveillance cases.
  • Optimized the pre-launch of a front-office tool for individual customers requesting car loan approvals.
  • Helped to refactor the back-end system that connects major Nordic division applications.
Technologies: .NET, SQL, APIs, ASP.NET MVC, Bootstrap, Angular, TypeScript, NServiceBus, CI/CD Pipelines, DevOps

Co-founder | IT Leader

2014 - 2016
  • Co-founded Kytasoft for personal venture projects and to help other startups with great ideas.
  • Created a social network called Bindaloo to help people find new local buddies with whom to do activities.
  • Designed and customized projects for personal purposes and external startups, including CRM and eCommerce industries.
Technologies: .NET, SQL, APIs, ASP.NET MVC, Bootstrap, jQuery, Redux

Senior Software Engineer | Project Manager

2011 - 2016
Deutsche Bank
  • Participated in crafting organization-wide critical solutions for the risk division of the leading German bank, earning awards for efficiency and user experience.
  • Designed and developed from scratch strategic business intelligence solutions.
  • Worked on numerous projects, including market oversight control, internal risk workflow optimizations, and process automatizations.
Technologies: .NET, SQL, APIs, ASP.NET, Architecture

Senior Full-stack Developer

2009 - 2010
The Etailers
  • Developed an eCommerce platform to create customizable shops for different Spanish retailers.
  • Created a customized shop for the most important Spanish sunglasses retailer.
  • Implemented sophisticated architectural patterns and work methodologies.
Technologies: .NET, ASP.NET, C#, SQL

Senior Full-stack Developer

2007 - 2009
Near Technologies
  • Acted as the lead .NET developer in several on-demand projects, mainly in the financial and banking industry, including the biggest Spanish bank.
  • Developed a high-speed real-time news portal for traders to facilitate digesting information as quickly as possible in a categorized fashion.
  • Created a social platform to provide financial advice in exchange for virtual currency.
  • Helped and advised in other projects occasionally, such as a hotel booking reservation platform, an HR management desktop application, and a web portal for scholarship petitions.
Technologies: .NET, ASP.NET, C#, SQL

Full-stack Developer

2005 - 2007
Stardoc, Netlander, & Binacus Consulting
  • Gained my 1st professional experience in the latest software technologies and the .NET environment.
  • Developed a document management project based on an activity workflow and CRM for big corporate clients.
  • Built from scratch a dynamic web portal for the Spanish Maritime industry.
  • Collaborated on and enhanced projects in the e-learning and eCommerce industries.
Technologies: .NET, ASP.NET, SQL, C#, VB.NET, Windows Presentation Foundation (WPF), Oracle, IIS SQL Server, Windows Services, MySQL, Visual Basic .NET (VB.NET), Windows Forms (WinForms), C#.NET WinForms

Global Architecture Design
I transformed a poorly designed system into a scalable modern architecture of a top American fintech company. This included defining the cloud strategy with Azure, including all components, best principles, patterns, and code conventions. It set the path for all developers to work under the new framework.

Development of a Fintech App
I built a fintech app with complex functionalities requiring advanced background processing, calculations, and integrations. The app has a wide range of features, including trading, pre-defined portfolio models, savings, purchase discounts, subscription billing, donating, and an e-commerce wish list.

Redesign of a Simulation Learning Platform's Cloud, DevOps, and Apps Architecture
I transformed a Simulation Learning Platform's entire cloud, DevOps, and apps architecture. It had several long-standing issues that other engineers were not able to resolve. At the same time, I also doubled the speed performance of the apps, reduced Azure cloud computer costs by almost half, and stabilized the user experience with a more solid architecture and monitoring tools.

Creation of a Personal Website
I created my personal blog, where I add unstructured content about my passions, hobbies, and other unique content. I also write blog articles about meditation, general awareness practices, and conscious investing.

Creation of an Oversight Tool for Deutsche Bank
I built a framework tool called BAMS from scratch to further strengthen the controls and transparency of the bank submissions of prices to external benchmarks. An independent supervisory workflow application was established within the market risk management system.

Build of AML Workflow Tool for Anti-money Laundering for Santander Bank
I built an AML workflow app from scratch for anti-money laundering surveillance cases. The tool contained a real-time dashboard to monitor and take quick action as needed, going through the required workflow.

Development of a Social Network Platform
I built a simple social network platform called Bindaloo to connect people doing the same activities and hobbies in cities worldwide. The platform tried to match the same activity preferences in an open community.

Founding of Kytasoft
I co-founded Kytasoft to build elaborated IT works with the vision to grow the value of any kind of business by creating solutions that combine a relentless commitment to quality and efficiency based on market demands.

Enhancement of the Building Modeling App
I refactored and enhanced different parts of the architecture and infrastructure of a building modeling app for manufacturers. The back end consisted of an API connecting different platforms and front-end apps using various technologies and mechanisms of communication.

Architecture of an Email Marketing Platform
I refactored the architecture of an email marketing platform that includes a wide range of top-market advanced features to help you produce and deliver effective email campaigns. It manages and optimizes campaigns, while the user can monitor the results in real-time.

IT and Fintech Consultancy
I offered consultancy to clients in the fintech and banking industry. I took several courses on finance and economics, and I am also a long-term investor with a diversified strategy and portfolio. I implemented complex banking and accounting solutions over the years.
2003 - 2007

Bachelor's Degree in Computer Science

Universidad Tecnológica Nacional - Buenos Aires, Argentina


Azure Solutions Architect Expert



Azure Administrator Associate



NServiceBus, jQuery, REST APIs, Stripe, Entity Framework, React, LINQ, Stripe API, SignalR, Windows Forms (WinForms), Web API


Microsoft Access, Git, Azure DevOps Services, Bitbucket, Microsoft Team Foundation Server, GitHub, Jira, Microsoft Visual Studio, Adobe Photoshop, Confluence, Lucidchart, Microsoft Excel, Azure Logic Apps, Azure App Service, Visual Studio, Gulp, Adobe Illustrator, RabbitMQ, C#.NET WinForms, Microsoft Teams, Azure Kubernetes Service (AKS), Visio, Kafka Streams


Razor, ASP.NET Core 2, ASP.NET Web Forms, ASP.NET Identity, Angular, ASP.NET, ASP.NET Core, ASP.NET Web API, .NET, Bootstrap, ASP.NET MVC, Blazor, .NET Core, gRPC, Windows PowerShell, Entity Framework Core, Tailwind CSS, ASP.NET Core MVC, Redux, Windows Presentation Foundation (WPF)


T-SQL (Transact-SQL), ASP.NET Razor, Visual Basic, Visual Basic .NET (VB.NET), C#, TypeScript, TypeScript 2, SQL, XML, HTML5, JavaScript, CSS, C#.NET, HTML, C++, GraphQL, Excel VBA, CSS3, VB, YAML, Active Server Pages (ASP), Visual Basic for Applications (VBA), VB.NET, Python


Software Testing, Responsive Web Design (RWD), Continuous Integration (CI), Web Architecture, Continuous Deployment, Code First, Unit Testing, Agile Software Development, Scrum, Waterfall Development, Azure DevOps, DevOps, Microservices, Enterprise Application Architecture, Test-driven Development (TDD), Requirements Analysis, REST, Database Design, Microservices Architecture, CQRS, Behavior-driven Development (BDD), Event Sourcing, Application Architecture, Event-driven Architecture, API Architecture, Agile, Clean Architecture, UI Design, UX Design, DevSecOps, Lambda Architecture, Building Information Modeling (BIM), App Development


Azure Notification Hub, Amazon Web Services (AWS), Azure, Web, Windows, Docker, Azure Functions, Azure Event Hubs, Mobile, Oracle, Kubernetes, Microsoft Power Automate, Telerik, Amazon EC2, Oracle Database


Azure Blobs, Azure Websites, Azure SQL, Azure Active Directory, SQL Architecture, MySQL, JSON, Microsoft SQL Server, Azure Table Storage, Redis, Relational Databases, Azure Cosmos DB, Azure SQL Databases, SQL Stored Procedures, Azure Queue Storage, Azure Cloud Services, SQL Server 2014, Database Architecture, SQL Server Integration Services (SSIS), MySQL Server, PostgreSQL, Elasticsearch, NoSQL, MongoDB, Databases, IIS SQL Server, Data Pipelines

Industry Expertise

Banking & Finance, Accounting, E-learning, Project Management


Azure Service Bus, Integration Testing, Full-stack, Key Performance Indicators (KPIs), Enterprise Resource Planning (ERP), Financial Markets, Reporting, Financial APIs, Email Marketing, Financial Data, Bootstrap UI, Data Scraping, Big Data, APIs, UI Testing, Software Analysis, Data Architecture, Architecture, Requirements & Specifications, Content Management Systems (CMS), Customer Relationship Management (CRM), Web Services, Security, Enterprise Service Bus (ESB), .NET 6, CI/CD Pipelines, Finance, Solution Architecture, Technical Architecture, Microsoft Web, Cloud Architecture, API Integration, Webhooks, Trading, Enterprise Architecture, Payroll & Benefits, Windows Services, Cloud Platforms, Virtual Machines, Integration, System Architecture, Software Architecture, Excel Add-ins, WebAssembly, Consulting, RESTful Services, Data Processing, Web Applications, SaaS, Credit Risk, Fraud Analysis, Fintech, Workflow, Domain-driven Design (DDD), Message Queues, Software Development Lifecycle (SDLC), Enterprise Integration Patterns (EIP), Normalization, Single Sign-on (SSO), IIS, Legacy Software, Containerization, Distributed Systems, Leadership, Back-end, API Design, Stock Trading, Recommendation Systems, Third-party APIs, Technical Leadership, OAuth, Front-end, Cloud, Infrastructure as Code (IaC), Back-end Development, GitFlow, Serverless, Mapping, Payment APIs, Identity & Access Management (IAM), Code Review, Enterprise SaaS, SaaS Design, Multitenancy, Monitoring, Documentation, Microsoft Data Transformation Services (now SSIS), SOLID Principles, Marketing Technology (MarTech), Stripe Payments, User Interface (UI), Data Structures, Progressive Web Applications (PWA), Octopus Deploy, Windows Communication Foundation (WCF), AWS Cloud Architecture, Digital Asset Management, Research, Big Data Architecture, Full-stack Development, Software Development, IT Project Management, Data Analysis, Algorithms, Programming, Web Development, Diagrams, Planning, Debugging, Investment Banking, IT Consulting, Cloud Computing, Artificial Intelligence (AI), Azure Data Factory, Pipelines, OpenAI GPT-3 API, OpenAI GPT-4 API, Mobile Apps

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