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$50 USD / hour
Flag of RU
$50 USD / hour
It's currently 2:54 PM here
Joined July 25, 2021
1 Recommendation

Sergey K.


4.9 (15 reviews)
$50 USD / hour
Flag of RU
$50 USD / hour
Jobs Completed
On Budget
On Time
Repeat Hire Rate

Senior Full Stack | Blockchain Developer

My name is Sergey, and I’ve operated as a senior web and software developer for the past 15 years. Combined with my [login to view URL]. in Systems Engineering, those years have allowed me to build skills as a full-stack developer, specializing in writing smart contracts for DeFis and dApps as well as full stack web development through the use of PHP and JavaScript frameworks (especially blockchain-based applications). My blockchain experience is extensive, having worked with blockchain since 2016. I have built DeFis, Dapps and NFT minting projects, as well as having worked with smart contracts in Solidity and Rust. I am well-versed in the following programming languages: • PHP • Javascript • Solidity • C/C++/C# and backend setups: • Laravel • CodeIgniter • Node.js also the following front-end frameworks: • HTML5 • CSS • Javascript • JQuery • React • Angular I never back down from a project and can handle any setup or framework specifications you may need. Having worked with many blockchain companies like GrowthDefi, along with big companies like FEDEX, I’m confident not only in my abilities but my professionalism. I constantly stay ahead of the game, learning and mastering all the relevant software applications and tools necessary to create the most efficient web and software apps in the industry. If you’re interested in working with me or discussing a potential project, you can reach me through Freelancer, either via message or with the “Hire Me Now” button. Thanks for taking the time to read through my profile, and I hope to speak with you soon!
Freelancer PHP Developers Russian Federation

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Portfolio Items

Iost smart contract development for exchange feature
Built node.js based web application deals with IRC20 token
Giftingblock is a social, online gifting site that allows user to browse millions of products and add them to user Block to be shared across user network of friends.


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Showing 1 - 5 out of 15 reviews
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£150.00 GBP
It was a pleasure to work with Sergey. He was in constant communication, understood the brief perfectly and delivered a flawless solution first time. I'd happily work with him again on future projects.
PHP JavaScript Ruby on Rails AJAX WordPress
Flag of GB Adam H. @wordpresshoster7
6 days ago
$750.00 USD
Did not do the do the project and refused to refund. Claimed funds by disputing.
JavaScript HTML5 HTML Angular Tailwind CSS
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Flag of UZ Shokhrukh B. @shoxa19955
10 days ago
$1,500.00 USD
Sergey was a very passionate and understanding man and loved the work he did and so did I , he delivered the work on time and was very helpful in all the modifications I requested, I hope to work with him again soon.
PHP Codeigniter MySQL Software Development MariaDB
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Flag of SA Moemn B. @MoemnBagdady
1 month ago
$40.00 USD
Perfect! Very good human being, delivered on time, perfect price and very smart in what he does!
PHP JavaScript Web Scraping Software Architecture HTML
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Flag of LB Christian K. @Christiankaram19
2 months ago
$15.00 USD
Good job. Will hire again.
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Flag of ES Daniel K. @DanielKLM
2 months ago

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PHP 9 JavaScript 8 HTML 8 Software Architecture 3 HTML5 3

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