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$50 USD / hour
$50 USD / hour
It's currently 1:55 PM here
Joined July 25, 2021
2 Recommendations

Sergey K.


4.6 (29 reviews)
$50 USD / hour
$50 USD / hour
Jobs Completed
On Budget
On Time
Repeat Hire Rate

Senior Full Stack | Blockchain Developer Top 2%

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 builing the AI models and training and optimization of AI module, 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: • Python, Tensorflow, OpenCV • Ruby on Rails • Elixir, Phoenix • Golang • Javascript • Solidity • C/C++/C# • ASP.NET and backend setups: • Laravel • CodeIgniter • Node.js • Python • Django also the following front-end frameworks: • HTML5 • CSS • Javascript • JQuery • React • Angular Mobile development: • Unity • Android • Flutter • Swift 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 29 reviews
Filter reviews by: 1.0
₹12,500.00 INR
Fake team, no professionalism, just time waste.
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Flag of Rajit V. @Sonia1444
17 days ago
$124.00 USD
Worked hard to finf files
Web Security MySQL
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Flag of Marvin B. @Marvinbotts
1 month ago
$150.00 USD
This is my returning work with Sergey and i must say that he has patiently listened to all my requirements and did my job exactly as needed. My work was a challenging one and he did an amazing job with it Thanks Sergey will come back
PHP JavaScript Python Codeigniter HTML
+1 more
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Flag of Leroy M. @supercrocvw
2 months ago
$20.00 CAD
The project is not completed according to the dispute
PHP MySQL Laravel Stripe
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Flag of Jason M. @lunchboxjay123
2 months ago
€250.00 EUR
Nice Freelancer. I am very happy with his work.
PHP JavaScript Python Codeigniter HTML
+1 more
Flag of Nuria V. @pericopo
2 months ago

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Top Skills

PHP 21 HTML 21 JavaScript 17 Python 9 Codeigniter 9

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