Qijiong Jiang, Developer in Madrid, Spain
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Qijiong Jiang

Verified Expert  in Engineering

Web Development Developer

Location
Madrid, Spain
Toptal Member Since
January 22, 2021

Qijiong is an experienced software engineer focused on the information technology and services industry. He is skilled in Python, Django, Node.js, machine learning, and blockchain technologies. He led a team that implemented an international payment system based on Ethereum integrated with a core banking system. Qijiong is a blockchain consultant with a strong engineering background and a Master's degree focused on machine learning.

Portfolio

Advanced Blockchain
Solidity, Blockchain, Ethereum, Ethereum Smart Contracts
DXC Technology
Blockchain, Machine Learning
Banco Santander
Node.js, Kubernetes, Hyperledger Fabric, Docker, Ethereum, Solidity...

Experience

Availability

Full-time

Preferred Environment

MacOS, Ubuntu, PyCharm, Vim Text Editor

The most amazing...

...system I've implemented as the team led was an international payment system based on Ethereum integrated with a core banking system.

Work Experience

Ethereum Smart Contract Developer

2021 - 2023
Advanced Blockchain
  • Developed a cross-chain application based on Ethereum virtual machine (EVM) contracts.
  • Built decentralized finance and derivative products using Solidity, Hardhat, and Truffle.
  • Developed smart contracts and light clients for bridges and cross-chain messaging protocols.
Technologies: Solidity, Blockchain, Ethereum, Ethereum Smart Contracts

Principal Technical Consultant

2019 - 2021
DXC Technology
  • Created a fund marketplace based on the EVM blockchain.
  • Developed tools for email classification in the banking sector.
  • Built back end for an augmented reality application using HoloLens2.
Technologies: Blockchain, Machine Learning

Blockchain Consultant and Architect

2017 - 2019
Banco Santander
  • Developed an international payment system based on the Ethereum network (money tokenization, currency exchange).
  • Created an Information sharing system (AML application, sharing information between different Norkoms) based on Hyperledger Fabric.
  • Developed a report on remote extraction PoC for FCA (Financial Conduct Authority, UK) based on Hyperledger Fabric.
  • Delivered a smart contract audit for a cryptocurrency bond project (https://www.coindesk.com/santander-settles-both-sides-of-a-20-million-bond-trade-on-ethereum).
Technologies: Node.js, Kubernetes, Hyperledger Fabric, Docker, Ethereum, Solidity, Ethereum Smart Contracts, Blockchain, Decentralized Finance (DeFi), CI/CD Pipelines, Fintech

Blockchain Developer

2017 - 2018
Ethic Hub
  • Developed the first version of Ethichub's P2P lending platform based on Ethereum.
  • Organized and successfully carried out a pre-ICO for project fundraising.
  • Participated in technical meetings about designing the Ethichub solution.
Technologies: Ethereum, Solidity, Ethereum Smart Contracts, Blockchain, Decentralized Finance (DeFi), CI/CD Pipelines, Fintech

Software Developer

2014 - 2017
Paradigma Digital
  • Developed Telefonica's low-cost brand "Tuenti" website in south American countries: Peru, Ecuador, Argentina, and Ecuador.
  • Created Vodafone's low-cost brand "Lowi" website for Spain.
  • Deployed an internal digital transformation tool to score corporate digital transformation readiness.
Technologies: Django ORM, Django CMS, Django, Python, Web Development, CI/CD Pipelines

Anti-spam Developer

2013 - 2014
Douban
  • Developed anti-spam strategies to detect bot-based spam users.
  • Built tools to ban bot-based spam automatically in real-time via user profiling and interaction fingerprints.
  • Processed vast amounts of data in real-time based on big data technologies. Douban is a leading social network with millions of visits daily.
Technologies: Storm, Django, Spark, Python

eCommerce Website

http://www.newnesskids.com
I developed an eCommerce solution based on Django-oscar for one of Spain's largest kids' fashion brands. I customized it for their wholesale solution and integrated a national payment solution and shipping service to offer a smooth user experience. I also maintained it. The system has been operating for four years.

Solidity Engineer at Panoptic

https://panoptic.xyz/
Developed smart contracts, 3rd-party smart contracts integrations, tests, and deployment scripts.

Technology used: Solidity, Hardhat, OpenZeppelin, Uniswap v3, TypeScript, JavaScript, The graph, etc.

Smart Contract Developer at Composable Finance

http://composable.finance
Developed smart contracts for trustless bridges based on the IBC protocol, 3rd-party smart contracts integrations, tests, and deployment scripts.

Technology used: Solidity, Hardhat, Foundry, OpenZeppelin, Balancer, MakerDAO, Protobuf, Uniswap v3, TypeScript, JavaScript, etc.

Head of Engineering at Umoja Labs

Led a small team to develop an on/off ramp API service and a dashboard for fund disbursement.

Technologies used: Python, Django, Solidity, TypeScript, React, React Native, Hardhat, Celo, Avalanche, and Circle.
2011 - 2013

Master's Degree in Machine learning

Universidad Autónoma de Madrid - Madrid, Spain

2007 - 2011

Bachelor's Degree in Computer Science

Universidad Autónoma de Madrid - Madrid, Spain

FEBRUARY 2021 - PRESENT

Sequence Models

Coursera

JANUARY 2021 - PRESENT

Convolutional Neural Networks

Coursera

JANUARY 2021 - PRESENT

Improving Deep Neural Networks: Hyperparameter Tuning, Regularization, and Optimization

Coursera

DECEMBER 2020 - PRESENT

Neural Networks and Deep Learning

Coursera

APRIL 2013 - PRESENT

Machine Learning

Coursera

Libraries/APIs

Node.js, Django ORM, jQuery, React

Tools

Git, Vim Text Editor, PyCharm, NGINX

Frameworks

Django, Truffle, Hardhat, Spark, Storm, Bootstrap

Languages

Solidity, Python, JavaScript, TypeScript, Python 3

Platforms

Ethereum, Hyperledger Fabric, Blockchain, Ubuntu, MacOS, Django CMS, Docker, Kubernetes, Chainlink

Storage

Databases

Paradigms

Scrum

Other

Smart Contracts, Decentralized Finance (DeFi), ERC-20, ERC-721, Ethereum Smart Contracts, Fintech, Crypto, Machine Learning, Text Classification, Web Development, CI/CD Pipelines, Foundry, Software Development, Computer Vision, Django-oscar, Deep Learning, Telegram Open Network (TON), Know Your Customer (KYC), Tokenization

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