Darko Kolev, Python Developer in Skopje, Macedonia
Darko Kolev

Python Developer in Skopje, Macedonia

Member since February 7, 2020
Darko specializes in Python and Node.js back-end systems but has experience with front-end JavaScript technologies as well. He's an engaging and proactive developer that loves to contribute to all parts of a project. He has expertise with payment systems, cryptocurrency, dashboards, and projects requiring precise work with real-time data. He writes quality and performant code and strives to deliver exceptional products.
Darko is now available for hire


  • Request Finance
    Solidity, TypeScript, Node.js, React, Blockchain, Ethereum...
  • BitcoinAverage
    WebSockets, REST APIs, InfluxDB, MongoDB, Linux, Redis, JavaScript, Angular...
  • Freelancer
    PostgreSQL, Linux, Stimulus, JavaScript, Django, Python



Skopje, Macedonia



Preferred Environment

Linux, WebStorm, PyCharm

The most amazing...

...project I've built is LifeHQ, a personal productivity app. I was the sole developer who also worked on marketing, sales, and product research.


  • Full-stack Blockchain Developer

    2021 - PRESENT
    Request Finance
    • Built end-to-end blockchain features, including smart contract deployment, event detection, and front-end integration using Solidity, TypeScript, and React.
    • Deployed smart contract across multiple EVM blockchains.
    • Used The Graph for smart contract event detection.
    Technologies: Solidity, TypeScript, Node.js, React, Blockchain, Ethereum, Ethereum Smart Contracts, Smart Contracts
  • Lead Developer

    2016 - 2020
    • Developed a Cryptocurrency exchange aggregator using Celery that polls data from over 50 exchanges in parallel and calculates average prices for Bitcoin and 300+ other cryptocurrencies.
    • Designed and implemented the BitcoinAverage REST API using Python and Tornado which is the main product of the company. Maintained and optimized this API for four years.
    • Built micro-service architecture for a scalable WebSocket API using Node.js that provides real-time prices and order-book updates to enterprise clients.
    • Initiated four types of payment options: PayPal, Stripe, BitPay, and OpenNode in Python.
    • Optimized the APIs to handle more requests with intelligent caching with Redis.
    • Delivered improvements on front-end systems built with plain JavaScript, AngularJS and Angular 8.
    • Stored time series history data in real time using InfluxDB.
    • Designed MongoDB architecture for storage of historical and real-time cryptocurrency data.
    Technologies: WebSockets, REST APIs, InfluxDB, MongoDB, Linux, Redis, JavaScript, Angular, Node.js, Python
  • Full-stack Django Web Developer

    2018 - 2019
    • Designed the architecture and developed LifeHQ, an all-in-one personal productivity application.
    • Performed market research, gathered requirements, talked to clients and implemented the app.
    • Built a to-do list module, journaling module, habit tracking module, and note-taking module using front-end JavaScript and StimulusJS.
    • Created a back-end system with Django and Python3. Designed the database system with PostgreSQL.
    Technologies: PostgreSQL, Linux, Stimulus, JavaScript, Django, Python
  • Back-end Developer

    2018 - 2018
    3P Development
    • Developed an API with Django and Django Rest Framework for an iOS mobile app in the medical industry for performing patient surveys.
    • Built a web-based dashboard for generating reports from collected data using Django and vanilla JavaScript.
    • Created the database for storing patient data securely and separate from identifiable information in PostgreSQL.
    Technologies: REST APIs, Django, Python
  • Blockchain Smart Contract Developer

    2017 - 2017
    Omic MD
    • Developed a Smart contract in Solidity on the Ethereum blockchain to be used for storing user credits and request approvals.
    • Built an adapter and API to interact with the smart contract from a web app.
    • Delivered a demo wallet project that demonstrated all capabilities of the smart contract.
    Technologies: Ethereum, Node.js, Solidity, Ethereum Smart Contracts, Smart Contracts


  • BitcoinAverage Cryptocurrency API

    I was the lead back-end developer on the project. I designed a micro-service architecture, developed the public-facing REST and WebSocket APIs, and implemented four types of payment methods: PayPal, Stripe, BitPay, and OpenNode. I optimized the exchange scraper that pulls data from 50+ exchanges and oversaw and maintained the production release of the app for multiple years.

  • LifeHQ: All-in-one Personal Productivity App

    This is a multi-module web application developed with Django on the back end and StimulusJS on the front end. It consists of a to-do list, journaling, note-taking, Pomodoro timer, and habit tracker modules all combined into a single, all-in-one productivity app. I developed LifeHQ as a personal project, something I would want to use for myself.
    I performed market analysis, researched competitors, and gathered requirements. I drafted the design and architecture of the system and implemented the full application, both front end and back end. I also oversaw and maintained the production release of the app for multiple years.

  • Focus Hub

    Social productivity application built with Node.js, MongoJS, Socket.IO, and StimulusJS. I designed the database, the back end, and front-end systems. I built the REST API in Node.js and developed the front end using StimulusJS and Bulma CSS. I implemented live updates and group chat using Socket.IO
    The idea of the application is to have a place where remote workers can work productively using customizable Pomodoro cycles and also share their work.

  • Articles on Technology, Business, and Productivity

    I have written technology documentation for APIs and software libraries, as well as content for my personal blog and the blog of my employer.
    API documentation: https://apiv2.bitcoinaverage.com
    Employer blog: https://medium.com/bitcoinaverage-blog
    Personal blog: https://focusmind.blog

  • Blockchain Development Video Course

    I created a course called Blockchain Development for Beginners. It consisted of five video tutorials explaining how to get started with blockchain development using Solidity on the Ethereum blockchain. It was showcased on a popular blog.


  • Languages

    Python, Solidity, SQL, JavaScript, TypeScript
  • Frameworks

    Django, Stimulus, Angular
  • Libraries/APIs

    REST APIs, Node.js, jQuery, React
  • Storage

    MongoDB, Redis, PostgreSQL, MySQL, InfluxDB
  • Other

    Tornadoweb, Algorithms, WebSockets, Cryptocurrency APIs, Writing & Editing, Ethereum Smart Contracts, Smart Contracts
  • Platforms

    Ethereum, Linux, Blockchain
  • Tools

    PyCharm, WebStorm


  • Bachelor's Degree in Computer Science
    2010 - 2014
    Ss. Cyril and Methodius University - Skopje, Macedonia

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