Krystian Lieber, Developer in Brwinów, Poland
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Krystian Lieber

Verified Expert  in Engineering

Software Developer

Location
Brwinów, Poland
Toptal Member Since
July 29, 2016

Krystian has 12 years of software development experience, including business process analysis, software design, coding, testing, and deployment. He always focuses on understanding the business's nature and exploiting the advantages of using technology to maximize the organization's benefits. Krystian strongly believes in technology-driven business.

Portfolio

Trilogy
TypeScript 3, Amazon Web Services (AWS), Serverless, FinOps...
Self-Employed
AngularJS, Microsoft SQL Server, Java
Optiva
Java, Google Cloud Platform (GCP), Google Cloud Spanner, Low Latency...

Experience

Availability

Part-time

Preferred Environment

Git, TypeScript, Java, IntelliJ IDEA, Amazon Web Services (AWS), Serverless, Cloud Native

The most amazing...

...thing I've designed and coded was a framework for comparing different classification algorithms.

Work Experience

VP of Software Engineering

2021 - PRESENT
Trilogy
  • Brought a new cloud cost optimization software to market.
  • Prepared detailed specs to allow a multinational, distributed team of remote developers to deliver at scale, with speed and quality.
  • Oversaw the launch and migration to the new version, working with customers to reach 100% customer success.
Technologies: TypeScript 3, Amazon Web Services (AWS), Serverless, FinOps, Cost Reduction & Optimization, Cost Cutting, Cost Analysis

Owner | Developer

2015 - PRESENT
Self-Employed
  • Created an application to ease the process of post office complaints for county court bailiffs.
  • Build a system for a new office from scratch.
  • Migrated the main application from SQL Server to PostgreSQL.
  • Created dozens of small applications to optimize business processes.
Technologies: AngularJS, Microsoft SQL Server, Java

Senior Software Developer

2017 - 2020
Optiva
  • Led the developers on a Cloud Migration Project, the first world OCS in the cloud.
  • Migrated existing system to cloud native technologies using Kubernetes and Google Cloud Platform.
  • Worked with customer engineering teams building excellent relations.
Technologies: Java, Google Cloud Platform (GCP), Google Cloud Spanner, Low Latency, Online Charging Systems (OCS), Telecom Business Support Systems (BSS)

IT Manager

2010 - 2017
County Court Bailiff Office
  • Created an intelligent document management system using OCR and machine learning using JAVA.
  • Built integration applications for faster data exchange with other government organizations.
  • Developed dozens of small applications to optimize business processes.
  • Designed and deployed a virtual desktop infrastructure.
Technologies: Microsoft SQL Server, Java

Researcher

2012 - 2013
Warsaw University of Technology
  • Created a toolkit for analysis of different machine learning algorithms.
  • Developed a document classification part of the PASSIM/SYNAT (the repository of the people, organizations and events in Polish science).
  • Worked with a team of researcher to integrate systems.
  • Prepared a presentation for a project conference.
Technologies: Java

PSIR

Toolkit for analysis of different machine learning algorithms.
• Written in Java.
• Defines interfaces for implementations of algorithms.
• Different dataset preparation methods.
• Running algorithms with various parameters.
• Distributed, concurrent executions of tasks.
• Gathering results.
• Calculating statictics and scores.
• Reporting using templates (Apache Velocity) to TeX.

ZUS Application Integration

Integration of the customer application with ZUS (Polish social insurance institution) platform.

No API is available therefore the whole integration is made using selenium and simulation of the client using browser.

The project started in 2011. It underwent major changes in 2013, the platform was renewed therefore the client part of the platform was changed and it is still is use.

Automatic Billing System

The system discovers electronic invoices in PDFs added to customers system, then detects all data: invoice issuer, bank account number, payment amount, invoice number, and generates position in company's books and a wire transfer
2012 - 2014

Master of Science in Computer Science, Computer Information System Engineering

Warsaw University of Technology - Warsaw, Poland

2008 - 2012

Bachelor of Science in Computer Science, Computer Information System Engineering

Warsaw University of Technology - Warsaw, Poland

Libraries/APIs

Selenium WebDriver

Tools

Mercurial, Apache Maven, Git, Grunt, Bower, Java Concurrency, IntelliJ IDEA

Frameworks

Swagger, JPA, JUnit, Selenium, Spring, AngularJS

Paradigms

Agile Software Development, Concurrent Programming

Languages

Java, T-SQL (Transact-SQL), SQL, Python, R, TypeScript, TypeScript 3

Platforms

NetBeans, Windows, Amazon Web Services (AWS), Cloud Native, Google Cloud Platform (GCP)

Storage

Microsoft SQL Server, H2, Neo4j, Google Cloud Spanner

Other

VMware ESXi, Remote Desktop Services, Web Scraping, Serverless, Low Latency, Online Charging Systems (OCS), Telecom Business Support Systems (BSS), FinOps, Cost Reduction & Optimization, Cost Cutting, Cost Analysis

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