Aleksander Izemski, Developer in Poznań, Poland
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Aleksander Izemski

Verified Expert  in Engineering

Full-stack Developer

Poznań, Poland
Toptal Member Since
May 17, 2022

Aleksander is a front-end engineer specializing in React and has experience writing RESTful APIs with Node.js, Express.js, and Mongoose. He's led the whole process, from first contact with the client through development to production deployment. He also conducted academic research in machine learning and published a paper about usage reinforcement learning in education. Aleksander enjoys facing challenges and new experiences while meeting clients' requirements.


Python 3, OpenAI GPT-3 API, Prototyping, MVP Design, System Design, AWS IoT...
JavaScript, Next.js, Mongoose, MongoDB, REST, React, Ubuntu Server...
TypeScript, Python, React, Pytest, React Redux, Jest, Python 3




Preferred Environment

React, Node.js, Express.js, Amazon Web Services (AWS), Artificial Intelligence (AI), OpenAI GPT-3 API, Python 3, Next.js, Machine Learning, Data Science

The most amazing...

...project I've worked on is a production management app where users can see the progress of the process with an estimated time of finishing.

Work Experience

Machine Learning Engineer

2022 - PRESENT
  • Performed competitive analysis, designed a solution, and successfully launched an MVP with positive initial feedback from stakeholders.
  • Co-developed a solution for content writing and made it friendly for non-technical users.
  • Automated the process for data mismatch correction, which resulted in the reduction of data that needed to be checked by 74%.
Technologies: Python 3, OpenAI GPT-3 API, Prototyping, MVP Design, System Design, AWS IoT, No-code Development, Low Code, Web Scraping, Amazon SageMaker, Docker, Back-end

Full-stack Developer

2020 - PRESENT
  • Developed a web platform that helped a production company increase their performance and have a more predictable process.
  • Designed the whole platform based on the client's needs.
  • Set up and configured Ubuntu Server to serve both front and back of the platform.
  • Described the requirements, created tasks, and then delegated them.
  • Handled negotiations with clients regarding the rate, deadline, and what could be done.
Technologies: JavaScript, Next.js, Mongoose, MongoDB, REST, React, Ubuntu Server, Styled-components, JSX, System Architecture Design, Database Architecture, Negotiation, Ubuntu 16.04, Back-end

Software Engineer

2021 - 2022
  • Developed a platform that clients around the world use.
  • Tracked and fixed bugs using Jira as a reporting tool.
  • Reviewed and assigned tasks for working students and interns.
  • Rewrote the deprecated React components with a new UI library.
Technologies: TypeScript, Python, React, Pytest, React Redux, Jest, Python 3

Junior Front-end Developer

2020 - 2020
  • Created a custom landing page based on a given project.
  • Managed multiple WordPress-based websites by adding custom PHP functions.
  • Developed a WordPress-based shop with a WooCommerce widget.
Technologies: JavaScript, jQuery, CSS, Bootstrap, HTML, WordPress, PHP, Adobe Experience Design (XD), Photoshop CS6


2019 - 2019
Chaos Gears
  • Used AWS Lambda that scraped data and saved them to S3.
  • Created a scraper that got AWS pricing data for services.
  • Integrated two AWS Lambda functions with each other.
Technologies: Serverless, Amazon Web Services (AWS), Python

Online Tutoring Platform

A React- and Java-based platform that allowed a student to find a tutor with specific skills and ratings and then schedule and run an online class.

I developed the front end and integrated it with Stripe to manage the transactions.

Furniture Production Scheduler and Workforce Manager

I had the distinct opportunity to spearhead the development of a web application for a reputable furniture producer. This wasn't just any application; it was designed to revolutionize their production management. My vision was to incorporate advanced algorithms that could predict the finishing time of production processes, taking into account the nuances of workforce availability.

I also integrated a feature that facilitated the assignment of workers to different workplaces. This ensured that the workforce was always used in the most optimal manner, avoiding any production bottlenecks. But I didn't stop there. Recognizing the importance of real-time oversight, I implemented a live tracking system, allowing managers to oversee the progress of processes in real time.

Throughout this project, I was involved in every phase. From the initial discussions to understanding the client's unique needs to closely collaborating with the development team, refining algorithms, and even the rigorous beta-testing phase, I was there, ensuring that the application met and exceeded expectations. The result? A game-changing platform that enhanced the company's production efficiency, predictability, and overall operational excellence.
2021 - 2022

Master's Degree in Artificial Intelligence

Poznań University of Technology - Poznań, Poland

2017 - 2021

Bachelor's Degree in Computer Science

Nicolaus Copernicus University - Toruń, Poland


React, Node.js, REST APIs, API Development, TensorFlow, PyTorch, jQuery, React Redux, Stripe API


Mongoose, Adobe Experience Design (XD), Photoshop CS6, JSX, Pytest, PM2, Amazon SageMaker


TypeScript, Python, JavaScript, HTML, Python 3, Java, C++, UML, SQL, CSS, PHP, GraphQL


Express.js, Spark, Bootstrap, Next.js, Jest


Responsive Web Design (RWD), REST, Data Science


Databases, MongoDB, Database Architecture


Amazon Web Services (AWS), WordPress, Ubuntu 16.04, AWS IoT, Docker


Algorithms, Machine Learning, Front-end, Full-stack Development, Networks, System Administration, Discrete Mathematics, Calculus, Deep Learning, Computer Vision, Natural Language Processing (NLP), Artificial Intelligence (AI), Reinforcement Learning, Deep Reinforcement Learning, Data Visualization, Decision Support Systems, Statistical Learning, Serverless, Ubuntu Server, Styled-components, System Architecture Design, Negotiation, Axios, Generative Pre-trained Transformers (GPT), OpenAI GPT-3 API, Prototyping, MVP Design, System Design, No-code Development, Low Code, Web Scraping, Back-end

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