Bartosz Frąckowiak, Developer in Warsaw, Poland
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Bartosz Frąckowiak

Verified Expert  in Engineering

Bio

Bartosz is a seasoned software engineer with over a decade of experience focused on developing and leading projects in the IT sector. Passionate about software architecture, Bartosz has a proven ability to identify and drive strategic programs from inception to launch and thrives in collaborative, team-oriented, and ambiguous environments. Specialized in several technologies, programming languages, and frameworks, Bartosz is an asset to any team.

Portfolio

Exemplar Human Services, LLC
Technical Leadership, .NET, Agile, Architecture, Database Architecture, ASP.NET...
EcoVadis
Management, .NET, Architecture, Design, Microservices Architecture...
Onward Travel Solutions Ltd
Laravel, Event-driven Architecture, Microservices, API Architecture...

Experience

  • .NET - 9 years
  • Software Design - 8 years
  • Object-oriented Programming (OOP) - 8 years
  • Distributed Systems - 6 years
  • Architecture - 6 years
  • Software Architecture - 6 years
  • Distributed Architecture - 5 years
  • Management - 4 years

Availability

Full-time

Preferred Environment

Linux, Slack, Windows, Visual Studio, Visual Studio Code (VS Code), JetBrains Rider

The most amazing...

...things I've done were developing a formal language to validate software architecture and redesigning a 15-year-old platform into a microservices architecture.

Work Experience

[Toptal Teams] Tech Lead

2023 - 2023
Exemplar Human Services, LLC
  • Conducted a code review of the current MVP, taking into consideration the architecture vision, the context of the application, security, and available resources.
  • Defined the technical approach (technical flows, tech architecture, and recommended tech stack).
  • Provided solutions architecture (the ability to prove the technology).
  • Designed, built, and configured applications to meet business processes and application requirements.
  • Defined architecture vision and evolution approach to achieve the goal, considering lose coupling, testability, maintainability, and time-to-market needs in the project context.
  • Defined the CI/CD process and evolution for scaling pipelines with the size of the teams.
Technologies: Technical Leadership, .NET, Agile, Architecture, Database Architecture, ASP.NET, APIs, C#, Azure, Data Architecture, Data Structures, CI/CD Pipelines

Software Architect | Senior Staff Engineer

2022 - 2023
EcoVadis
  • Designed the architecture for the business domain and handled technical product ownership and road-map planning with business departments.
  • Migrated a legacy monolith application to a microservice architecture.
  • Introduced workflow processes to ensure a seamless migration from legacy systems.
  • Created, audited, and consulted on the architecture of multiple areas of the platform.
  • Oversaw the technical development of several team members.
  • Led a team in the development and rollout of a microservices platform.
Technologies: Management, .NET, Architecture, Design, Microservices Architecture, Service-oriented Architecture (SOA), Microservices, Azure, Kubernetes, C#.NET, Microsoft SQL Server, HTML, ASP.NET, C#, LINQ, Enterprise Architecture, Scalability, Platforms, Containers, Analytics, Test Automation, Team Management, XML, Serverless Architecture, Elasticsearch, REST APIs, Databases, Event-driven Programming, Scaling, Back-end, SQL, Technical Leadership, Web Application Architecture, .NET Core, REST, Test-driven Development (TDD), Azure DevOps, ASP.NET Core, Back-end Architecture, Back-end Development, Microsoft Azure, HTTP REST, Entity Framework Core, Software Architecture, Leadership, Third-party APIs, Cloud Architecture, Azure SQL, Application Architecture, System Architecture, OpenAPI, REST API Architecture, System Architecture Design, Technical Documentation, Diagrams, Renewable Energy, Event-driven Architecture, Distributed Architecture, Endpoint Security, Entity Framework, Team Leadership, GitFlow, Project Management, Agile Project Management, NoSQL, Database Design, API Integration, Real-time Data, Windows PowerShell, Microsoft Graph API, T-SQL (Transact-SQL), JSON Web Tokens (JWT), Web App Development, Minimum Viable Product (MVP), API Architecture, Node.js, Back-office System Development, Web Architecture, DevOps, Continuous Integration (CI), Solution Architecture, OpenAI API, Creative Problem Solving, CI/CD Pipelines, Data Analysis, Microsoft Visual Studio, System Design, Integration, IIS, Windows Services, Legacy Software, DB, GraphQL, Enterprise Software, Software Project Management, Agile, Agile Software Development, Data Structures, Database Architecture

Laravel Expert | Microservices Migration

2022 - 2022
Onward Travel Solutions Ltd
  • Reviewed a microservice architecture, consulting existing solutions in the monolith architecture and defining the migration strategy.
  • Defined the migration vision from monolith to micro-service.
  • Delivered a vision document treating technical concepts proven to work in a microservices architecture.
Technologies: Laravel, Event-driven Architecture, Microservices, API Architecture, Software Architecture, APIs, Travel, RESTful Microservices, Microservices Architecture, Architecture, Web Architecture, Solution Architecture, OpenAI API, Creative Problem Solving, CI/CD Pipelines, System Design, Integration, PHP, IIS, DB, GraphQL, Enterprise Software, Software Project Management, Agile Software Development, Data Structures, Database Architecture

Technical Leader | Staff Engineer

2017 - 2022
EcoVadis
  • Introduced CI/CD processes, domain-driven design methodology with event-driven architecture, and data-driven decision-making processes.
  • Designed the applications' architecture, prototyped solutions, and developed back-end services.
  • Cooperated with solution architects and technical leaders and established a software craftsmanship culture.
  • Implemented and spread an open-source initiative at the organization.
  • Migrated a legacy monolith application to a microservice architecture, scaling out 15-year legacy projects.
  • Oversaw the technical development of several team members.
Technologies: .NET, Microservices, Service-oriented Architecture (SOA), Elasticsearch, APIs, OpenAPI, Azure, C#.NET, Microsoft SQL Server, HTML, ASP.NET, C#, LINQ, Enterprise Architecture, Platforms, Scalability, Containers, Analytics, Test Automation, Team Management, XML, Serverless Architecture, REST APIs, Databases, Event-driven Programming, Scaling, Back-end, Kubernetes, SQL, Technical Leadership, Web Application Architecture, .NET Core, REST, Test-driven Development (TDD), Azure DevOps, ASP.NET Core, Back-end Architecture, Back-end Development, Microsoft Azure, HTTP REST, Entity Framework Core, Software Architecture, Leadership, Third-party APIs, Cloud Architecture, Azure SQL, Application Architecture, System Architecture, REST API Architecture, System Architecture Design, Technical Documentation, Diagrams, Renewable Energy, Event-driven Architecture, Distributed Architecture, .NET 4, Endpoint Security, Entity Framework, Team Leadership, GitFlow, Project Management, Agile Project Management, NoSQL, Database Design, API Integration, Real-time Data, Windows PowerShell, T-SQL (Transact-SQL), JSON Web Tokens (JWT), Web App Development, Minimum Viable Product (MVP), API Architecture, Node.js, Back-office System Development, Web Architecture, DevOps, Continuous Integration (CI), Solution Architecture, OpenAI API, Creative Problem Solving, CI/CD Pipelines, Microsoft Visual Studio, System Design, IIS, Windows Services, Legacy Software, DB, GraphQL, TypeScript, Enterprise Software, Software Project Management, Agile, Agile Software Development, Data Structures, Database Architecture

Team Leader | Technical Leader

2018 - 2018
EcoVadis SAS
  • Oversaw all the activities within the team while creating its working workflow processes and cooperation methodologies with other teams.
  • Designed the architecture and developed several applications while managing a team of seven developers.
  • Audited, changed, and upgraded the architecture of the existing software projects, refactoring to scale-out applications.
Technologies: .NET, Software Design, Management, Architecture, C#.NET, Microsoft SQL Server, HTML, Azure, ASP.NET, C#, LINQ, Enterprise Architecture, Platforms, Scalability, Containers, Test Automation, Team Management, XML, Elasticsearch, REST APIs, Databases, Event-driven Programming, Scaling, Back-end, SQL, Technical Leadership, Web Application Architecture, .NET Core, REST, Test-driven Development (TDD), Azure DevOps, ASP.NET Core, Back-end Architecture, Back-end Development, Microsoft Azure, HTTP REST, Entity Framework Core, Software Architecture, Leadership, Third-party APIs, Cloud Architecture, Azure SQL, ASP.NET Web Forms, Application Architecture, System Architecture, REST API Architecture, System Architecture Design, Technical Documentation, Diagrams, Renewable Energy, Event-driven Architecture, Distributed Architecture, .NET 4, Endpoint Security, Entity Framework, Team Leadership, GitFlow, Project Management, Agile Project Management, NoSQL, Database Design, API Integration, Real-time Data, Windows PowerShell, T-SQL (Transact-SQL), Web App Development, Minimum Viable Product (MVP), API Architecture, Node.js, Back-office System Development, Web Architecture, DevOps, Continuous Integration (CI), Solution Architecture, OpenAI API, Creative Problem Solving, CI/CD Pipelines, Microsoft Visual Studio, Windows Services, Legacy Software, DB, GraphQL, TypeScript, Enterprise Software, Software Project Management, Agile, Agile Software Development, Data Structures, Database Architecture

Team Leader

2017 - 2018
Cybercom Group
  • Managed and grew an offshore team of 3-8 developers.
  • Designed the architecture and developed several applications.
  • Provided technical support to the sales team by creating project requirement documentation and estimating projects' costs and duration.
Technologies: Management, Design, Agile Delivery, C#.NET, Microsoft SQL Server, HTML, Azure, ASP.NET, C#, LINQ, Team Management, XML, REST APIs, Databases, Back-end, SQL, Technical Leadership, .NET Core, Azure DevOps, Back-end Architecture, Back-end Development, Microsoft Azure, Software Architecture, Leadership, Full-stack, Full-stack Development, Cloud Architecture, Azure SQL, ASP.NET Web Forms, System Architecture, System Architecture Design, Diagrams, .NET 4, Microsoft Excel, Microsoft Access, Entity Framework, Software Consulting, Razor, Team Leadership, Project Management, Agile Project Management, Database Design, Consulting, T-SQL (Transact-SQL), Minimum Viable Product (MVP), Web Architecture, DevOps, Continuous Integration (CI), Creative Problem Solving, CI/CD Pipelines, Microsoft Visual Studio, Data Processing, IIS, DB, GraphQL, Software Project Management, Agile, Agile Software Development, Database Architecture

Senior Software Consultant

2015 - 2017
Cybercom Group
  • Designed the architecture and developed several applications.
  • Audited, changed, and upgraded the architecture of the existing software projects.
  • Improved scalability attributes of the existing applications.
  • Provided technical support to the sales team by creating project requirement documentation and estimating projects' costs and duration.
Technologies: .NET, Azure, APIs, ASP.NET MVC, C#.NET, Microsoft SQL Server, HTML, CSS, jQuery, ASP.NET, C#, LINQ, Web Development, XML, REST APIs, Databases, Back-end, SQL, Azure DevOps, Back-end Architecture, Back-end Development, Microsoft Azure, SOAP, Software Architecture, Full-stack, Full-stack Development, Windows Presentation Foundation (WPF), Cloud Architecture, Azure SQL, ASP.NET Web Forms, SendGrid, .NET 4, Microsoft Excel, Microsoft Access, Angular, Entity Framework, Software Consulting, Razor, Database Design, Consulting, T-SQL (Transact-SQL), Continuous Integration (CI), Creative Problem Solving, Microsoft Visual Studio, System Design, Machine Learning, Data Science, IIS, .NET MAUI, Blazor, DB, Agile, Agile Software Development, Database Architecture

.NET Developer

2010 - 2013
Invent On Sp. z o.o.
  • Handled core development, including analysis, design, and coding.
  • Delivered software according to the clients' requirements.
  • Maintained software applications within the required quality.
Technologies: .NET, ASP.NET, MSSQLCE, Databases, Microsoft SQL Server, HTML, CSS, jQuery, C#, LINQ, Web Development, XML, Back-end, SQL, Back-end Development, Full-stack Development, Windows Presentation Foundation (WPF), .NET 4, Microsoft Excel, Microsoft Access, Software Consulting, Database Design, T-SQL (Transact-SQL), Continuous Integration (CI), Creative Problem Solving, Microsoft Visual Studio, IIS, DB

Intern

2010 - 2010
Allegro
  • Developed a full-text search engine and customized it for the existing software.
  • Gathered requirements and use-cases for the full-text search functionality.
  • Tested it with the search capabilities available on the market at the time.
Technologies: PHP, Apache Lucene, PostgreSQL, HTML, CSS, jQuery, Web Development, Back-end, Back-end Development, Creative Problem Solving, IIS, DB

Mobile Monitor

Custom software that provides car sale offers from eCommerce platforms with extremely low delay –according to customer feedback and view counters, around 95% of the offers are discovered before competitive software.

3CX Integration Services

Concurrent 3CX integration service software between 3CX Phone System and the custom Call Center software. It provides a real-time synchronization service between the phone connection line and the back-office application.

Builder for the Future

https://www.b4f.buildercorp.pl/
It is a platform dedicated to architects and building engineers to engage and share local construction sites. The platform includes modules for managing events, contests, surveys, mailing, users, and certificates.

I was responsible for the system design and execution, from prototyping with the client to implementation and production. I also have been in charge of its maintenance since April 2017.

The platform hosts 100 thousand users and registers 500 daily active users.

Minizet

Minizet is a startup company that created a platform that allows payments with an accuracy of 0.00001zł. I was the C++ back-end developer in charge of creating an internal web application with a serving list and statuses of payments for particular users.

Desta

http://www.desta.pl/
This project is a platform dedicated to an accounting company. The platform includes modules for invoices, files, mailing, and client communication.

I was responsible for the system design and execution, from prototyping with the client to implementation and production. I also have been in charge of its maintenance since April 2017.

The platform hosts 100 active users.
2013 - 2017

PhD in Software Engineering

University of Warsaw - Warsaw, Poland

2008 - 2013

Master's Degree in Computer Science

Nicolaus Copernicus University - Toruń, Poland

JANUARY 2014 - PRESENT

Functional Programming Principles in Scala

Swiss Federal Institute of Technology Lausanne via Coursera

JANUARY 2013 - PRESENT

ITA105 Object-Oriented Programming

Microsoft IT Academy Programmer

JANUARY 2010 - PRESENT

SPSS Technology Junior Expert

IBM

Libraries/APIs

OpenAPI, REST APIs, Entity Framework, OpenAI API, LINQ, Node.js, Apache Lucene, jQuery

Tools

Visual Studio, Microsoft Visual Studio, Slack, GitHub, SendGrid, Microsoft Excel, Microsoft Access, JetBrains Rider, Google Analytics

Languages

C#, C#.NET, SQL, T-SQL (Transact-SQL), HTML, XML, GraphQL, Java, Scala, HTML5, CSS, XSD, XAML, JavaScript, PHP, TypeScript

Frameworks

.NET, ASP.NET MVC, ASP.NET, .NET Core, ASP.NET Core, Entity Framework Core, .NET 4, Bootstrap, Windows Presentation Foundation (WPF), ASP.NET Web Forms, Windows PowerShell, JSON Web Tokens (JWT), .NET MAUI, Blazor, Realtime, Angular, Razor, Laravel

Paradigms

Agile, Object-oriented Programming (OOP), Management, Service-oriented Architecture (SOA), Microservices, Microservices Architecture, Web Application Architecture, REST, Back-end Architecture, Application Architecture, REST API Architecture, Event-driven Architecture, Agile Project Management, Database Design, API Architecture, Web Architecture, DevOps, Continuous Integration (CI), Agile Software Development, Event-driven Programming, Test-driven Development (TDD), Azure DevOps, Functional Programming, Test Automation, Serverless Architecture

Platforms

Azure, WordPress, Linux, Windows, Visual Studio Code (VS Code), Windows Server, Software Design Patterns, Kubernetes, Xamarin

Storage

MSSQLCE, Databases, Microsoft SQL Server, Azure SQL, DB, Database Architecture, PostgreSQL, Elasticsearch, MySQL, NoSQL

Industry Expertise

Project Management

Other

Software Development, Architecture, Software Design, Distributed Systems, APIs, Design, Web Development, Back-end, Technical Leadership, Back-end Development, Microsoft Azure, HTTP REST, Software Architecture, Leadership, Third-party APIs, Full-stack Development, System Architecture, System Architecture Design, Technical Documentation, Distributed Architecture, Software Consulting, Team Leadership, GitFlow, Consulting, API Integration, Real-time Data, Web App Development, Minimum Viable Product (MVP), Solution Architecture, Creative Problem Solving, CI/CD Pipelines, System Design, IIS, Windows Services, Legacy Software, Enterprise Software, Software Project Management, Data Structures, Agile Delivery, Low-latency Software, Concurrency, Enterprise Architecture, Scalability, Team Management, Scaling, Full-stack, Cloud Architecture, Diagrams, Endpoint Security, Microsoft Graph API, Back-office System Development, Data Analysis, Platforms, Integration, Machine Learning, Data Processing, Data Science, Statistics, HTTP Server, Containers, Analytics, SOAP, Renewable Energy, Travel, RESTful Microservices, Trading, Data Architecture

Collaboration That Works

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