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Wonjoon Lee

wnjoon@gmail.com
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INTRODUCE

🇺🇸

Experienced in distributed systems and security, and currently working in the blockchain field using Hyperledger Fabric and Ethereum.

Currently working for making a new token economy through virtual assets with real value, such as digital currency and security tokens.

Interested in how to provide good services to users through blockchain and web3 in the future. Furthermore, recently focus on how to tokenize the experience of users and express it through a blockchain service as value.

Generally use Java and Go as the main backend languages, and use Solidity for contract development. Running a private blog in spare time to share what I learned and ideas.

🇰🇷

분산시스템, 보안 등의 분야에 경험이 있으며, 현재는 블록체인을 개발하고 있습니다. 하이퍼레저 패브릭과 이더리움을 이용하여 다양한 비지니스 환경에 블록체인 기술을 적용하였습니다.

현재는 디지털화폐, 토큰증권 등 실질적인 가치를 지닐 수 있는 가상자산을 통한 새로운 토큰 이코노미가 만드는 일에 집중하고 있습니다.

앞으로 블록체인과 web3를 통해 더 많은 사용자에게 좋은 서비스를 제공할 수 있는 방법에 관심이 많습니다. 특히 최근에는 사용자의 경험과 활동을 토큰화하고, 이를 중단되지 않는 특징을 갖는 블록체인 서비스를 통해 표현하여 자신의 가치를 표현할 수 있는 방법에 더 알아가고자 합니다.

주된 백엔드 언어로 Java, Go를 사용하며, 컨트랙트 개발에는 Solidity를 사용합니다. 글을 쓰는 것을 좋아하며, 학습한 내용을 다른사람들과 공유하기 위해 블로그를 운영하고 있습니다.

Latest Updated 2023. 01. 17 (D+782)

Wonjoon Lee

SKILL

Programming Languages

  • 3 Java
  • 3 Go
  • 2 C/C++
  • 3 Solidity
  • 2 JavaScript
  • 2 TypeScript

DevOps

  • 3 Docker
  • 3 Git
  • 2 Jenkins
  • 2 Maven/Gradle
  • 1 Kubernetes

Platform

  • 3 Hyperledger fabric
  • 3 Ethereum(Besu, Quorum)
  • 3 Linux(CentOS, Ubuntu)
  • 2 Naver Cloud

    Tools

    • Vscode
    • Eclipse
    • IntelliJ
    • Confluence
    • Slack
    • Vim
    • Geth
    • Truffle
    • Hardhat

    Certification

    • CKA(Certified Kubernetes Administrator)
    • CHFA(Certified Hyperledger Fabric Administrator)
    • Corda Certified Developer
    • 정보처리기사

      EXPERIENCE

      2023. 05 ~

      재직 중1년 11개월

      LG CNS

      Blockchain Software Engineer
      • Develop web3 services
      • Construct security token platform in various institutions
      • Skill Keywords
        BlockchainEthereumHyperledger BesuJavaGolangSolidity

      2022. 02 ~ 2023. 05

      1년 4개월

      Samsung Securities

      Senior Engineer
      • Construct Blockchain Platform based on ST(Security Token)
      • Develop smartcontract for security token using ERC1400
      • Develop Multi-sig smartcontract based on Gnosis SafeContract for reducing sign times in private network
      • Develop client application to connect with Quorum(Private Ethereum) network using golang
      • Configure platform and blockchain node server monitoring tools
      • Investige new technologies and prototype them on the platform
      • Skill Keywords
        BlockchainEthereumQuorumGolangSolidityDocker

      2018. 07 ~ 2022. 02

      3년 8개월

      LG CNS

      Blockchain Software Engineer
      • Construct and configure Hyperledger fabric-based blockchain system
      • Develop Hyperledger fabric-based smart contract using golang
      • Develop API application for smart contract transaction call using java
      • Design and implement smart contract logic for efficient processing of large amounts of data
      • Apply various consensus algorithms (Raft, Kafka-zookeeper)
      • Test and optimize chaincode performance using nGrinder
      • Construct node monitoring system using ELK, Prometheus
      • Construct NFT marketplace prototype using Ethereum and develop smart contract to swap ERC20 with ERC721
      • Construct NFT marketplace between Ethereum mainnet and private network based on Hyperledger Fabric
      • Skill Keywords
        BlockchainHyperledger FabricEthereumJavaGolangSolidityDocker

      2016. 01 ~ 2018. 03

      2년 3개월

      Ever More Security

      Software Engineer
      • Develop internal systems of security equipment called NADP(Non-Addressable Data Protection) that do not have IP or other accounts
      • Develop a real-time key exchange system between communication sessions using Netfilter and iptables-based packet capture system
      • Apply for a patent of real-time key exchange mechanism
      • Skill Keywords
        Packet forwardingKey exchangeCryptographicC

      PROJECT

      2023. 06 ~

      Mirae Asset security token platform for issuance and distribution

      LG CNS
      • 미래에셋증권 토큰증권 발행 유통 플랫폼 구축 프로젝트
      • Design issuance / distribution system by EVM-based blockchain
      • Develop EVM client platform focused on Hyperledger Besu and Quorum using golang
      • Adjust Kafka to send transaction asynchronously
      • Design and adjust RDBMS based storage for maintain useful information such as transaction history
      • Develop API gateway using fiber, mainly used in various of golang project
      • Design and Develop smart contract
        • Tokens (customized ERC20, 1400 for business requirements and legal issue in Korea)
        • Multisig, Orderbook(Multilateral counterparty trading), Whitelist and so on

      2022. 02 ~ 2022. 12

      ST platform construct project

      Samsung Securities
      • 증권형 토큰(Security Token) 플랫폼 구축
      • Construct blockchain platform using Quorum, private Ethereum network
      • Smart contract development for securities business using ERC1400, ERC721
      • Smart contract testing using hardhat with typescript
      • Re-constructing multi-sig using Gnosis open source for generating pre-confirmed signatures from off-chain
      • Private Ethereum client development using golang
      • Develop blockchain event listening module
      • Configure platform and blockchain node server monitoring tools

      2021. 11 ~ 2022. 02

      NFT platform construct project

      LG CNS
      • NFT 플랫폼 구축 사업
      • Design NFT platform system architecture connected with Public Mainnet
      • Construct and Design Hyperledger fabric based NFT platform system
      • Construct CEX(Central-Exchange) Wallet in public blockchain and Hyperledger Fabric

      2021. 08 ~ 2021. 11

      NFT marketplace system prototyping

      LG CNS
      • 블록체인 신기술 프로토타이핑 - NFT 마켓플레이스
      • Construct Ethereum private network based on PoW using geth and truffle
      • Develop Ethereum client application calling smart contract using Web3j
        • Using class wrapper to adjust smart contract to Java
        • Adjust 0xProtocol to Java without class wrapper to avoid internal problem by ABIEncoderV2
        • Develop smart contract using solidity to exchange different types of tokens seperately
        • Develop RESTful API to communicate with web3j
      • Develop marketplace prototype application using react

      2020. 12 ~ 2021. 03

      Central bank digital currency pilot system consulting

      LG CNS
      • 한국은행 CBDC 파일럿 컨설팅 사업
      • Analysis Bank of Korea business and propose blockchain data structure and system

      2020. 04 ~ 2020. 11

      Blockchain-based food safety data platform construction business

      LG CNS
      • 블록체인 기반 식품안전 데이터플랫폼 구축 사업
      • Construct Hyperledger Fabric-based multi-node blockchain system
        • Reduced server usage and construction complexity compared to Kafka-Zookeeper through Raft consensus algorithm
        • Measure and Optimize TPS using nGrinder
        • Configure service discovery policies for each peer node and reduce API call load
      • System configuration in an environment without internet (public cloud)
      • Application of a script that automatically checks blockchain server failure and restores it

      2020. 01 ~ 2020. 03

      Distributed Ledger Technology-based Simultaneous Securities Payment (PoC)

      LG CNS
      • 한국은행 분산원장기술 기반 증권대금동시결제 PoC
      • Construct Hyperledger Fabric-based blockchain system
      • Transfer of blockchain system according to cloud vendor change
        • Re-distribute blockchain node and chaincode using docker image

      2019. 08 ~ 2019. 12

      Jeollanam-do Provincial Government Blockchain-based Eco-Friendly Agricultural Products Distribution Platform and Service Construction

      LG CNS
      • 전남도청 블록체인 기반 친환경 농산물 유통 플랫폼 및 서비스 구축
      • Develop Agricultural product distribution business Smart contract in Hyperledger fabric
        • Implementation of multiple batch data (up to 90,000 cases per day) processing function (Golang)

      2018. 10 ~ 2019. 07

      Blockchain-based LG U+ Loss/Damage Compensation System Construction

      LG CNS
      • 블록체인 기반 유플러스 분실/파손보험 보상 시스템 구축
      • Develop damaged-compensation chaincode system
      • Code refactoring through chaincode common function module development

      2016. 11 ~ 2017. 07

      Development of dynamic encryption technology in non-address equipment

      Ever More Security
      • Develop Non-addressable communication equipment software
        • Developed and patented dynamic encryption key generation technology for each session
        • Configure a separate routing table in the form of {key,value} to check authentication between devices
        • Modifying the system kernel to work with various Linux vendors

      2014. 03 ~ 2016. 01

      Develop and Research Distributed system middleware

      Mobile Distributed Computing Lab: Chungnam National University
      • Research and Development
        • Participate in multi-directional listening structure research to improve DDS monitoring tool performance
        • Participate in Developing tools for DDS simulation
      • Papers
        • Dynamic key exchange system for independent cryptographic key generation per session (2017)
        • Performance comparison by key length of AES encryption using Non-Addressable Data Protection Devices (2017)
        • A Performance Simulator for DDS Network (2015)
        • A full-duplex listening structure for network and application monitoring (2014)

      PAPER, PRESENTATION

      2017. 12

      Dynamic key exchange system for independent cryptographic key generation per session

      Master's thesis
      • Korean: 세션 별 독립적 암호 키 생성을 위한 동적 키 교환 시스템
      • Proposal of an independent encryption key generation structure for each session applying the key exchange method to the 3-way handshaking session configuration step
      • Paper: http://www.riss.kr/link?id=T14771241

      2017. 11

      Performance comparison by key length of AES encryption using Non-Addressable Data Protection Devices

      Conference paper - Author
      • Korean: AES 암호 방식에서의 암호 키 길이 변화에 따른 넌어드레스 장비의 성능 측정 및 비교
      • Proposal of data encryption/decryption performance improvement plan according to AES key length change in non-address device
      • Paper: https://www.koreascience.or.kr/article/CFKO201735553776135.pdf

      2015. 01

      A Performance Simulator for DDS Network

      IEEE - Participant

      2014. 11

      A full-duplex listening structure for network and application monitoring

      IEEE - Participant

      EDUCATION

      2014. 03 ~ 2018. 02

      Chungnam National University

      Master degree

      2007. 03 ~ 2014. 02

      Chungnam National University

      Bachelor degree
      v.1.0.0 / Github / Thanks for Outsider
      Next.js v10.0.1 / React.js v17.0.1 / Bootstrap v4.5.3