Piotr Jachowicz, Developer in Warsaw, Poland

Piotr Jachowicz

Software Developer

Warsaw, Poland
Toptal Member Since
September 13, 2018

Piotr is a full-stack .NET developer with significant experience working with various JavaScript frameworks and libraries, including Vue.js, React, and Angular. Piotr is a quick learner, so he’s willing and able to learn new skills needed on any particular project rapidly. Piotr is in the process of getting certified as an Azure Cloud Architect, and he is also a member of Toptal Speakers Network.

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ASP.NET, Web API 2, Vue, SCSS, Agile, SQL, RabbitMQ, Zoho API
Multiple Coding Academies
Windows Communication Framework (WCF), Entity Framework, SQL, jQuery, Angular...


Warsaw, Poland



Preferred Environment

Windows, Git, Visual Studio Code (VS Code)

The most amazing...

...project I've worked on was creating an Angular app embedded into an existing desktop app for ease of a later transition to a full web app.

Work Experience

2019 - PRESENT

Full-stack .NET Lead Developer

  • Developed integration with third-party APIs such as DocuSign and Zoho for collaborative work on documents.
  • Worked on automation tools such as an auto-assignment feature that allowed users to create rules that triggered automatic filling out of form fields when creating contracts.
  • Introduced Vue.js to a legacy .NET Web Forms application and started modernizing the platform to a SPA architecture. Oversaw the process of rewriting logic and views to the new architecture.
  • Developed a new component in Vue.js that was used to define complex conditions based on field values, used throughout the application in many features.
  • Oversaw the creation of coding standards and started a discussion about code quality management in the company.
Technologies: ASP.NET, Web API 2, Vue, SCSS, Agile, SQL, RabbitMQ, Zoho API
2018 - PRESENT

Senior Developer | Vue.js, Angular, and .NET

Santander Denmark (via ProData Consult)
  • Maintained and developed a new functionality on Santander Consumer Bank Denmark's main web page and platform.
  • Developed and maintained the front-end layer of Santander Denmark's main page.
  • Developed the Santander Finland webpage using React and Episerver.
Technologies: React, .NET, Angular, Vue
2016 - PRESENT

IT Trainer

Multiple Coding Academies
  • Designed and conducted multiple workshops for beginner-level developers concerning various full-stack web technologies like Angular 6, .NET Web API, Basics of C#, CSS, SCSS, jQuery, and more.
  • Designed and conducted multiple expert-level workshops for large companies such as the advanced development of WCF services, design patterns and code quality in C#, and advanced JavaScript.
  • Advised on the planned range of training and their scope.
Technologies: Windows Communication Framework (WCF), Entity Framework, SQL, jQuery, Angular, .NET
2018 - 2020

Azure Developer

911Weather.com (via Toptal)
  • Maintained and rewrote the newer version of a mobile app back end in Node.js.
  • Created a deployment pipeline along with a test environment for the client.
  • Developed modern tooling for the client with the front end in Angular and back end in Node.js and .NET.
  • Implemented a back end for subscriptions as in-app payments for the Apple Store and Google Play Store.
  • Maintained and developed a Microsft SQL database and an API in Node.js that utilized this database.
  • Refactored a legacy service that processed weather data written in C#.
Technologies: Angular, Node.js, Azure
2019 - 2019

Full-stack Angular Developer

ForagerOne (via Toptal)
  • Developed features on the company's main page and the educational platform.
  • Worked on both the front-end and the back-end layer.
  • Refactored legacy code and improved the performance of the existing solution on the platform.
Technologies: Angular, Node.js, TypeScript
2018 - 2019

Freelance Angular Developer

Expedien, Inc. (via Toptal)
  • Created a taskboard in Angular according to the design.
  • Built multiple components based on wireframes provided by the design team.
  • Cooperated with the designers and back-end developers to ensure the proper quality of the provided solution.
Technologies: Angular
2017 - 2018

.NET Web Developer

  • Refactored the existing code to use design patterns and best practices.
  • Developed a service in .NET Core to be used for new pricing model calculations.
  • Maintained the largest recruitment platform in the UK.
Technologies: Octopus Deploy, TeamCity, jQuery, Microsoft SQL Server, ASP.NET Core
2017 - 2017

.NET Lead Developer

  • Managed the work of a team of four full-stack developers.
  • Mentored the team and enforced Scrum principles which ensured the quality of the Scrum process.
  • Created and enforced coding standards which ensured the quality of solutions created by the team.
  • Transitioned the development from a London-based team to a Warsaw-based team.
  • Created a design of the new architecture for new and existing applications.
Technologies: SQL, Entity Framework, Bitbucket, Git, Knockout (Knockout.js), jQuery, Windows Communication Framework (WCF), Web API 2, ASP.NET MVC 5
2016 - 2016

.NET Web Developer

KMD Poland
  • Developed a web application that handles the complex management for utility companies in the Denmark market. Built the front end in Angular and the back end in .NET Web API 2.
  • Implemented a set of controls with a validation framework for the application, making the development process significantly quicker.
  • Ensured the high quality of the development solution by proposing and implementing code quality enhancements.
Technologies: Gulp, Git, IBM Db2, Angular, ASP.NET Web API
2015 - 2015

Junior .NET Developer

AXA Direct Solutions
  • Supported a large, multi-tenanted insurance platform for AXA Group UK.
  • Worked remotely with a team mostly located in London.
  • Developed a new design for the home insurance product sales flow.
Technologies: Microsoft SQL Server, jQuery, Knockout (Knockout.js), ASP.NET MVC
2013 - 2014


PwC (PricewaterhouseCoopers, Poland)
  • Maintained and conducted workshops for a desktop application facilitating the financial reporting process.
  • Built an entire platform, including the web app, desktop app, and web services for voting for the Polish Film Awards.
  • Developed multiple web apps used for gathering financial data from users.
  • Contributed to the statutory financial audit as an auditor, gaining knowledge about accounting processes.
Technologies: jQuery, Microsoft SQL Server, Entity Framework, ASP.NET MVC, Windows Communication Framework (WCF), Windows Presentation Foundation (WPF), .NET


App.OfferAutomation.com | Development and Technical Management

On this project, I helped deliver a web app (the front end was built in Angular 5 and the back end in ASP.NET). My primary role was to ensure the overall delivery, acting as a technical manager.

I mostly performed code reviews, ensuring the highest quality of the delivered solution. I also facilitated communication between the developers working on the project and the client, took part in the recruitment process of new developers, proposed the high-level architecture of the solutions, provided insight with hosting, deployment, and so on. I also created a continuous deployment pipeline using Jenkins.

TotalJobs Recruiter Platform Pricing Model Change

This was a large project that involved 15 teams, working together to change how the business worked on TotalJobs.co.uk, the largest recruitment platform in the UK.

My role, as a member of a team, was to implement the back-end logic and database layer of a new pricing model for the company. The project ended up being a big success with the sales of the recruitment product licenses rising significantly.



CSS, HTML5, JavaScript, C#, HTML, TypeScript, SQL, SCSS


.NET, .NET Core, ASP.NET Web API, Entity, Swagger, Angular, ADO.NET, Express.js, ASP.NET Core, Windows Communication Framework (WCF), ASP.NET MVC, ASP.NET MVC 5, Knockout (Knockout.js), Windows Presentation Foundation (WPF), ASP.NET


Vue, Vue 2, React, jQuery, AutoMapper, Node.js, Zoho API, Entity Framework, Web API 2


Git, Bitbucket, Jenkins, TeamCity, Azure DevOps Services, Jira, Visual Studio, Gulp, RabbitMQ


Agile, Scrum, REST, FluentValidation


Visual Studio Code (VS Code), Azure, Windows, Amazon Web Services (AWS)


MVC Frameworks, WCF Web Services, GitFlow, APIs, Front-end, Episerver, User Interface (UI), Octopus Deploy, Cloud


MSSQLCE, Microsoft SQL Server, IBM Db2


2011 - 2014

Licentiate's Degree in Management

Warsaw University of Technology - Warsaw, Poland

2009 - 2014

Master of Engineering Degree in Electrical Engineering

Warsaw University of Technology - Warsaw, Poland


MARCH 2021 - MARCH 2023

Microsoft Azure Developer Associate



Microsoft Azure Fundamentals



Professional Scrum Master I



Microsoft Certified Solutions Developer