Alexander Kulakov, Developer in Saint John's, Saint John, Antigua and Barbuda
Alexander is available for hire
Hire Alexander

Alexander Kulakov

Verified Expert  in Engineering

Software Developer

Saint John's, Saint John, Antigua and Barbuda
Toptal Member Since
August 30, 2013

Alexander is an experienced Python developer seasoned with years of solving real-life problems using math and common sense. Alexander has successfully completed many projects through Toptal and prides himself on being able to satisfy every one of his clients.


Byteworks, LLC
Python, REST APIs, JavaScript, Vue, Django REST Framework, Vuetify...
Juju Inc
Python 3, JavaScript, Django, REST, Vue, Celery, Elasticsearch, AngularJS... (via TopTal)
Django REST Framework, Celery, MySQL, AngularJS, Python, Django, Django ORM...




Preferred Environment

Git, Linux, Docker, Amazon Web Services (AWS), PostgreSQL, Elasticsearch, Celery, ECMAScript (ES6), Vue

The most amazing...

...program I've developed was written in 1991 using Clipper to solve the problem of finding the optimal schedule and delivery route of concrete to building sites.

Work Experience

Senior Developer

2023 - 2023
Byteworks, LLC
  • Developed the integration between ConnectWise and APIs to make seamless data synchronization. Django REST framework was used on the back end to implement Webhooks and REST API.
  • Developed integration configuration and management web UI based on Vue and Vuetify.
  • Built a set of custom Docker images and configured Docker Compose for reliable and flexible deployment.
  • Acted as the sole developer on the project.
Technologies: Python, REST APIs, JavaScript, Vue, Django REST Framework, Vuetify, Docker Compose, PostgreSQL, Full-stack Development, Django

Senior Software Developer

2015 - 2022
Juju Inc
  • Created the initial API implementation by porting existing code from Falcon Web Framework to Django REST framework, speeding up development and moving from working prototype to MVP stage earlier.
  • Oversaw the deployment using the AWS Elastic Beanstalk multi-container Docker platform that allowed to use the same set of Docker images for both development and production. Docker Compose was used locally.
  • Developed a set of background tasks using Celery and AWS SQS as a broker.
  • Created a periodic task scheduler using AWS EventBridge and AWS Lambda.
  • Led the back-end team in the migration from Python 2 to Python 3 and then from Django 2 to Django 3.
  • Added the search feature to the project using Elasticsearch and AWS OpenSearch.
  • Participated in the early stage of web UI development. AngularJS was used initially but later on, we switched to Vue. The component libraries used were element-ui and Vuetify.
  • Mentored new team members to get them up to speed with the existing codebase.
  • Improved database queries performance using Django ORM features to drastically reduce the number of queries made for a given ORM request.
  • Convinced the back-end team and led the migration from MySQL to PostgreSQL. Complex database query performance was improved. MySQL-related shortcomings were eliminated.
Technologies: Python 3, JavaScript, Django, REST, Vue, Celery, Elasticsearch, AngularJS, Docker, Docker Compose, Git, AWS Lambda, Amazon Simple Queue Service (SQS), Amazon EventBridge, Django ORM, Linux, Python, Test-driven Development (TDD), JSON, Amazon EC2, Angular, Amazon Web Services (AWS), Architecture, APIs, REST APIs, Twilio API, Full-stack Development, Django REST Framework

Senior Python Developer

2014 - 2015 (via TopTal)
  • Solved performance problems related to non-effective database queries.
  • Developed a module to build Django ORM queries that can pre-load data to greatly reduce the number of database queries needed to retrieve the same amount of data.
  • Implemented a star rating calculation routine that does not suffer from performance issues.
  • Developed a script to detect South migration conflicts between a GitHub repository and its open pull-requests, as well as any Git branch, local or remote.
  • Participated in project refactoring aimed at decoupling brands and consumer parts of the site.
Technologies: Django REST Framework, Celery, MySQL, AngularJS, Python, Django, Django ORM, Linux, Test-driven Development (TDD), Amazon Web Services (AWS), APIs, REST APIs, Full-stack Development

Software Engineer

2014 - 2014 (via TopTal)
  • Designed and developed an ESI-application that would assemble compound documents from Amazon S3 and the local cache.
  • Developed a front-end application for real-time monitoring and control of an ESI back-end using AngularJS.
  • Designed and developed an application to integrate with Facebook Public Feed API using Flask and gevent.
  • Developed background tasks to parse Facebook Public Feed data and future enhance it with data gathered via Facebook Graph API.
  • Developed a Celery task to retrieve and normalize RSS-feeds from thousands of sources.
  • Developed a module to filter data collected from different sources using the Elasticsearch Percolator feature. Implemented an adaptive rate control to prevent overloading.
  • Assisted with the development of MongoDB to Elasticsearch data migration utility.
Technologies: Amazon S3 (AWS S3), Elasticsearch, AngularJS, JavaScript, PostgreSQL, Gevent, Flask, Python, Linux, Test-driven Development (TDD), JSON, Amazon Web Services (AWS), APIs, Full-stack Development

Senior Python Developer

2014 - 2014 (via TopTal)
  • Developed a platform for background tasks like importing of external data and data validation using Celery.
  • Created a Django admin interface to control the background job queue.
  • Identified and fixed performance issues in existing Python code.
  • Participated in the design and development of migration from MongoDB to PostgreSQL.
Technologies: PostgreSQL, Celery, Amazon S3 (AWS S3), Django, Linux, Python, Test-driven Development (TDD), APIs, REST APIs, Full-stack Development, JavaScript

Full-stack Django Developer

2013 - 2014
Digital First Ventures (via Toptal)
  • Developed the back end of using Python/Django.
  • Created a reusable Django application to track visitors using Google Analytics.
  • Created a RESTful API for an AngularJS front-end using the Django REST Framework (
  • Integrated asset management with the existing Django application to better control content stored on Amazon S3.
  • Created Celery tasks for background image processing (
Technologies: Celery, Amazon S3 (AWS S3), MySQL, Django REST Framework, Django, Python, Django ORM, Linux, JavaScript, APIs, Full-stack Development

Software Developer and Project Manager

2002 - 2013
Ajax Call Centres Ltd
  • Created a web application to monitor and control core company's business processes.
  • Developed FastCGI/WSGI server that is capable of handling thousands of simultaneous long-polling connections.
  • Involved in analysis and design of migration of legacy system (IBM Informix 4GL, PHP) to Python-based solution (Pylons/Pyramid, SQLAlchemy, Spread Toolkit).
  • Designed and developed communication library used as a backbone for development of distributed applications.
  • Participated in the design of the company's development processes and policies.
  • Designed and implemented measures and policies to improve the company's Internet security infrastructure and ability to comply with PCI SSC requirements.
Technologies: Python, IBM Informix-4GL, NGINX, SQLAlchemy, Linux, JavaScript, Docker, Full-stack Development

Java Developer

2001 - 2002
  • Improved performance of back-end server for the SeeStorm product family.
  • Increased performance and reliability of the protocol used by back end.
  • Assisted the QA department in improving test automation.
  • Improved automated daily builds and testing for the back-end server.
  • Contributed to setting up automated source code checking for compliance with company coding standards.
Technologies: Linux

A FastCGI/WSGI server developed to handle thousands of simultaneous long-polling connections using gevent coroutine-based networking library.
It was published on PyPI and GitHub as my contribution to the open-source community.

Breve Template Renderer for Pyramid Web Framework
A renderer that simplifies the usage of the Breve template engine in Pyramid applications.
This was my contribution to the open-source community. Although it's a tiny one, it was pretty popular while the Breve template engine was popular as well.

Telegram Bot That Uses Open AI to Make a Conversation
This was a coding challenge I was given not long ago. I had to demonstrate my ability to become familiar with OpenAI, Hugging Face Hub, Pinecone, and LangChain and use them to build a Telegram bot. It took me a couple of days to complete it, and since it was not part of any job, I decided to keep it open for anyone on GitHub.


JavaScript, Python, ECMAScript (ES6), Python 3


Django REST Framework, Django, AngularJS, Angular, Flask, Vuetify


Django ORM, Gevent, SQLAlchemy, Twilio API, REST APIs, Vue, Telegram Bot API


Linux, Amazon EC2, Amazon Web Services (AWS), Docker, AWS Lambda


APIs, Full-stack Development, Architecture, Amazon EventBridge, OpenAI GPT-4 API, LangChain, Pinecone, Hugging Face Hub, Pydantic


Celery, NGINX, Git, Docker Compose, Amazon Simple Queue Service (SQS), IBM Informix-4GL


Amazon S3 (AWS S3), PostgreSQL, Elasticsearch, JSON, MySQL, Redis


Test-driven Development (TDD), REST