Konstanty Orzeszko
Verified Expert in Engineering
Full-stack Developer
Warsaw, Poland
Toptal member since December 11, 2021
Konstanty is a seasoned software engineer with experience spanning across various back-end and mobile environments. As an expert in software development and architecture, he understands that clean code and a good foundation are essential. With his systems administration knowledge and console scripting, he created CI/CD pipelines for many projects. Konstanty uses behavior-driven development and domain-driven design to significantly improve stakeholders' satisfaction with the developed product.
Portfolio
Experience
- APIs - 9 years
- C# - 9 years
- REST - 8 years
- DevOps - 6 years
- Microservices - 5 years
- ASP.NET MVC - 4 years
- Python - 2 years
- Behavior-driven Development (BDD) - 2 years
Preferred Environment
ASP.NET MVC, Behavior-driven Development (BDD), DevOps, SQL, Python, Flutter, Architecture
The most amazing...
...thing I've developed is the eDO App, ranked #7 as the productivity app in the App Store that utilizes NFC to read data from the Polish ID.
Work Experience
Lead Software Engineer
PricewaterhouseCoopers (PwC)
- Led and supervised the back-end development team working in a microservices architecture based on .NET 8 and Azure.
- Built ETL/ELT processes leveraging Azure Functions, Durable Functions, and Event Grid.
- Defined and implemented Master Data architecture, ensuring consistency and referential integrity across the platform.
- Developed core back-end components for financial computation, large-scale data processing, and inter-service communication.
- Integrated Azure AI Search and Cosmos DB for fast, intelligent data retrieval and analytics.
- Oversaw CI/CD processes, quality standards, and architectural governance in Azure DevOps.
- Collaborated closely with Data Engineering and AI teams to design optimized data pipelines.
- Delivered a cloud-native, data-driven EPR platform automating compliance reporting and financial calculations for multinational clients.
Lead ASP.NET Developer
Polish Security Printing Works
- Developed the OAuth 2.0-based back,end for identity management and personal data sharing.
- Facilitated the online event stormings via Miro. Documented results and supervised development.
- Designed and supervised the usage of strict project architecture.
- Collaborated with the DevOps team on Kubernetes deployment on the on-premise cloud.
- Created multiple test suites to mimic partner integrations with Azure Web Apps, Azure Static Web Apps with Blazor WebAssembly (Wasm), and Azure Functions with C#.
Full-stack Flutter and .NET Developer
PLATONIC Tech UG
- Fixed bugs from previous versions of the application.
- Revamped the mobile UI entirely based on Figma prototypes.
- Automated the CI/CD of the Azure back end and both Android and iOS applications.
- Reduced server response times in critical places by a factor of 20.
Flutter Developer
Jacob Levitt
- Developed new functionalities based on saving application states between loads.
- Moved the back end from a slow WordPress solution to a blazingly fast CDN server. Optimized the costs of serving high-quality photos.
- Helped in the process of transferring ownership on both the Play Store and App Store. Also launched new versions of the apps.
Developer Screener
Toptal
- Achieved a higher than usual satisfactory rate of interviewed rejected developers, thanks to my soft skills.
- Trained new screeners by either letting them shadow my calls or by coworking background checks on candidates.
- Engaged in recruitment processes of over 230 candidates, performing code reviews and checking architectural knowledge and soft skills.
Xamarin Team Leader
Polish Security Printing Works
- Created, led, and managed a team of three Xamarin developers, one back-end developer, two testers, and one analyst. I delivered every project on time.
- Followed the Scrum methodology, facilitated planning, presented every increment during sprint reviews, and handled stakeholder interactions.
- Implemented the screens and flows designed by GFX and UX teams via Adobe XD.
- Created and maintained the CI/CD pipeline, including running unit tests on mobiles, local automated UI testing, UI testing on AppCenter cloud farm, and deployment on multiple testing groups and respective stores.
.NET Developer
Polish Security Printing Works (PWPW)
- Participated in developing the ERP system designed to handle the Polish ID production cycle comprehensively. The modules included ID ordering, document engraving, CR and QA, document shipping, and logistics.
- Used Jira as a task management system for developing new functionalities and bug fixing.
- Developed the custom-tailored CI/CD pipelines for a complex system deployed at restricted access areas without internet connectivity.
Experience
eDO App
https://apps.apple.com/pl/app/edo-app/id1503023855?l=plI was the lead back-end developer and participated in the architecture and design of mobile applications.
Mobile Big Family Card
https://www.gov.pl/web/mobywatel/karta-duzej-rodziny-mkdrPolish ID Personalization System (SPD)
Kontroler | Flutter App with IoC Communication
The application's main objective was to monitor crucial parts of the factory line, which are hard and time-consuming to do by hand.
KASA | Desktop Application Communicating with Credit Card Terminals
The solution was installed over numerous government offices, allowing them to accept card payments.
Educational App for Medical Professionals
Social App for Events
eDO Post (Secure e-Delivery System)
Election Oversight Platform
https://www.gov.pl/web/cyfryzacja/aplikacja-mezowie-zaufaniaEducation
Engineer's Degree in Computer Science
Polish-Japanese Academy of Information Technology - Warsaw, Poland
Skills
Libraries/APIs
Pandas, REST APIs, Xamarin.iOS, Xamarin.Android, React, Web API, Firebase iOS SDK, Facebook SDK, Azure Blob Storage API
Tools
Jira, Visual Studio App Center, Adobe Experience Design (XD), GitLab CI/CD, Pytest, Firebase Analytics, Fastlane, Sqitch
Languages
C#, XAML, Python, C#.NET, Dart, SQL, JavaScript
Frameworks
Windows Presentation Foundation (WPF), Entity Framework Core, ASP.NET MVC, .NET Core, .NET, ASP.NET Core, Flutter, ASP.NET, Blazor, iOS SDK, Android SDK, .NET 8
Paradigms
Model View ViewModel (MVVM), Mobile Development, Requirements Analysis, Desktop Web Design, Desktop App Development, REST, Asynchronous Programming, Behavior-driven Development (BDD), DevOps, Scrum, Test-driven Development (TDD), MVC Design, Azure DevOps, Microservices, ETL
Platforms
Xamarin, Android, iOS, Desktop, Windows Phone 8, Docker, Azure, Bluetooth Low Energy (LE), Firebase, Blockchain, Kubernetes, Azure Functions, Google Cloud Platform (GCP), Windows Desktop, Mobile, Azure AI Search, Databricks
Storage
PostgreSQL, Microsoft SQL Server, Cloud Firestore, Azure Cloud Services, SQL Server 7, Redis, Oracle SQL, Azure Websites, Azure Table Storage, Azure SQL, Azure Cosmos DB, Azure Storage, Google Cloud Storage
Other
DevExpress Controls, Xamarin.Forms, Code Review, Task Analysis, Technical Hiring, Interviewing, Source Code Review, Back-end, Mobile Apps, Front-end, Full-stack, Full-stack Development, Leadership, Software Design, Architecture, Minimum Viable Product (MVP), Cross-platform App Development, Event-driven Systems, Back-end Development, FastAPI, Large Language Models (LLMs), Industrial Internet of Things (IIoT), Internet of Things (IoT), Performance Optimization, Domain-driven Design (DDD), Waterfall Methodology, Marten, Observer Pattern, Akka.NET, Web Development, DevExpress, TCP/IP, APIs, Google Sign-in, Single Sign-on (SSO), Azure Durable Functions, Azure Databricks, Azure Data Lake, Serverless, ELT, Pub/Sub, GitOps, Argo CD, Google Cloud Functions
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