Błażej Kotowski
Verified Expert in Engineering
Software Developer
Linz, Austria
Toptal member since November 10, 2016
As someone who's been passionate about computer science since his tender years, Błażej has a lot of experience with various languages. The area that he chooses to work in mainly is back-end programming. He loves to craft perfect solutions, focusing on detail and reliability. Although Błażej likes to learn new things and take on challenges, he also finds much satisfaction in polishing up his skills.
Portfolio
Experience
Availability
Preferred Environment
Git, Zsh, Visual Studio Code (VS Code), MacOS, Linux, Vim Text Editor
The most amazing...
...thing I've coded is a visualization and sonification of the evolutionary simulation of aquatic life.
Work Experience
Database Architect | Senior Back-end Developer
[Enterprise] Asset Panda LLC
- Worked on the legacy codebase of an existing application to reduce the page load times drastically—in some cases, more than ten times.
- Increased modularity of the code by applying concepts like the single-responsibility principle or separation of concerns. Introduced PORO classes like services and query objects.
- Wrote and maintained a comprehensive coding standards guide document to be followed strictly by all the back-end developers in the team.
- Oversaw the work of up to five developers, planning the tasks, conducting detailed code reviews, and organizing regular code walkthroughs and training sessions.
- Designed a MongoDB database architecture from scratch for migrating the legacy data to the new application with a more optimal data model. The design process was conducted in consultation with MongoDB data modeling experts.
Full-stack Developer
BigMedia.ai
- Collaborated with an international team of freelancers on developing a suite of apps for collaborative video creation. Used Pivotal Tracker for task management and bug tracking.
- Created a cost-effective, on-demand Zoom users and meetings management system using Ruby on Rails and the Zoom Business API. Supported automatic profile creation, syncing between environments, and setting the maximum spending limit.
- Used GitHub and contributed the code for several API endpoints to one of the most popular open-source Zoom API client gems. Helped identify bugs and provide solutions.
- Helped develop a novel live streaming platform allowing for remote filming during the COVID-19 crisis. Supported multi-camera shooting and live state updates using Action Cable.
- Developed and maintained a comprehensive base of automated unit and integration tests using Capybara and RSpec. Implemented a custom testing helper for simulating API interaction based on JSON response fixtures.
Full-stack Developer
Advisor Analytics, LLC
- Used Terraform, provisioned an AWS infrastructure based on Elastic Beanstalk, and then deployed the app. Used custom security groups and a PostgreSQL RDS machine.
- Created a custom payment page for the client's product. Integrated PayPal with a custom payment flow and the Stripe online payment gates.
- Iteratively implemented several requested changes in the page's design using JavaScript, Webix, HTML, and CSS.
- Provisioned a separate EC2 machine within the infrastructure for a continuous delivery tool, GoCD. Created and managed testing and deployment pipelines with custom tasks provided in the form of bash scripts.
- Developed and maintained the integration tests for the most important product features using RSpec and Capybara.
Researcher | Full-stack Developer
MusicCritic — Music Technology Group (MTG)
- Maintained and developed an AI-driven web application for music practice teaching and automatic assessment. Implemented an API in compliance with the LTI standards.
- Helped prepare the pilot music teaching courses and led the technical integration with one of the biggest available MOOC platforms offering courses geared toward art, music, and creative technology.
- Coordinated a team of five music-technology and machine-learning doctoral researchers to integrate their research work into an existing web application.
- Built a standard and a guide for creating add-on AI modules to be easily installed into the application within the Django code.
- Prepared and executed a series of experiments to deal with the complexity of audio latency in the Web Audio API. By introducing optimizations, I reduced the recording app's latency significantly.
Ruby on Rails Developer
Clustrix
- Worked in a team of three to extend and maintain an admin interface consisting of a DBI app and GUI app for an existing scaled-out RDBS product.
- Optimized several complex MySQL queries generated by Rails to perform better in the product-specific environment and database.
- Upgraded two Rails apps with 20,000+ lines from Rails 4 and Ruby 2.2 to Rails 5 and Ruby 2.5.
- Refactored cluttered parts of code, introducing modern Rails concepts like services and concerns.
- Created and maintained tests for already existing and only introduced features.
Ruby on Rails Developer
22Fours/Synnaps
- Improved the code performance of an existing Ruby on Rails application.
- Developed an application that connected the parties involved in solving a refugee crisis.
- Adapted the existing Ruby on Rails code to three language versions.
- Implemented a couple of themes into the existing Ruby on Rails applications.
- Created a complex booking management system using RoR.
- Configured a lot of servers for various Ruby on Rails environments.
Full-stack Developer
SI Labs GmbH
- Constructed a library for scraping data from major German energy companies' APIs and websites.
- Created a location-based heuristic solution for expense optimization based on energy companies' offers and reports.
- Developed a solution generating PDF documents based on input data from many sources.
- Took part in designing the company's IT infrastructure.
- Maintained an application according to very strict security instructions.
- Contributed to the concept stage of designing innovative solutions.
- Built the fundaments for and maintained an Android application.
Ruby on Rails | PHP Analyst
teNeues
- Analyzed the condition and integrity of various Ruby on Rails applications.
- Analyzed the hardware and software setup of application servers.
- Analyzed various databases structure to assess the optimality of their design.
- Updated the code and fixed some major performance issues.
- Created a comprehensive rapport of code condition, possible code part usage, test coverage, and explanations of application behavior.
Web Developer
Restaurant Partner Polska Sp. z.o.o
- Created various marketing-related, data-based applications.
- Implemented graphic designs.
Android and Web (RoR) Application Developer
TheCheck.in
- Created an Android map-based application serving data from API.
- Maintained a Ruby on Rails application based on NoSQL database, storing large amounts of location-based data.
- Supported a Backbone.js application serving data from the API.
- Set up an application and database server.
Chief Technology Officer
Kipscore.com
- Created a web application for tournament organizing.
- Implemented an automatic payment system.
- Constructed a web scraper library—scraping sports players data from external websites.
- Developed a C application for serving the scraped data quickly.
- Built a WebSockets solution for observing the tournament progress.
- Designed and implemented a W3C valid website design.
- Created a Facebook application for joining and displaying the tournaments.
Chief Technology Officer
Jourmie.com
- Created a website application managing media storage.
- Implemented a graphic design.
- Executed an application and database environment.
- Configured a domain with a SSL certificate.
- Created a secure data storage system.
Web Developer
Mebella.pl
- Designed a W3C-valid website layout.
- Created a CMS.
- Configured the domain and hosting.
- Maintained the website changes.
Experience
Latent Space Divination
Master Thesis: Dualization of Rhythm Patterns
https://zenodo.org/record/4091469Preferly
Jourmie
Education
Master's Degree in Sound and Music Computing
Universidad Pompeu Fabra - Barcelona, Spain
Bachelor's Degree in Computer Science
Poznan University of Technology - Poznan, Poland
Certifications
Data Modeling
MongoDB University
MongoDB Performance
MongoDB University
The MongoDB Aggregation Framework
MongoDB University
MongoDB Basics
MongoDB University
Blockchain Developer
Coursera
Skills
Libraries/APIs
jQuery, Ruby on Rails API, Web Audio API, Facebook API, TensorFlow, Pandas, Web3.js
Tools
RSpec, Capistrano, Yeoman, Vim Text Editor, Git, Sublime Text, Zsh, NGINX, Docker Compose, Terraform, MongoDB Shell, MongoDB Atlas
Frameworks
Ruby on Rails (RoR), Django, Kohana, Ruby on Rails 5, Capybara, Truffle
Paradigms
Object-oriented Programming (OOP), Agile Software Development, Scrum, Concurrent Programming, Functional Programming
Languages
Python, JavaScript, C, Ruby, Java, Bash, HTML, CSS, Python 3, C++, PHP
Platforms
Amazon Web Services (AWS), MacOS, Linux, Unix, Heroku, Oracle, Docker, Blockchain, Visual Studio Code (VS Code)
Storage
MongoDB, PostgreSQL, Redis, MySQL, Amazon S3 (AWS S3), Databases
Other
Sound Design, Data Modeling, Algorithms, Data Structures, Music Production, Server Administration, Performance, GoCD, Music Information Retrieval (MIR), Digital Signal Processing, Deep Learning, Machine Learning, Artificial Intelligence (AI), Data Science, Technical Writing, Coding, Deep Neural Networks (DNNs), Art, Data Visualization, Data, Dimensionality Reduction, DApps
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