Serkan Kaplan, Software Architecture Developer in Stuttgart, Baden-Württemberg, Germany
Serkan Kaplan

Software Architecture Developer in Stuttgart, Baden-Württemberg, Germany

Member since March 4, 2021
Serkan is a seasoned software engineer with 14 years of experience in consultancy and in-house development. For the last four years, he's been working as a member of a rapid prototyping team at Daimler AG, focusing on blockchain projects. Previously, he worked as a consultant for different companies and projects for 6+ years. As a software consultant, he led development teams of up to ten developers and worked on employee relations, learning management, and eCommerce applications.
Serkan is now available for hire


  • Toptal Client
    Node.js, Ethereum, Solidity, Hardhat, ERC20, ERC721, MongoDB, PostgreSQL...
  • Harvey Nash
    Java, Kotlin, Corda, Solidity, PostgreSQL, Spring Boot, MongoDB...
  • The Debtvision
    Corda, Kotlin, Spring Boot, Digital Signatures, Software Architecture...



Stuttgart, Baden-Württemberg, Germany



Preferred Environment

MacOS, IntelliJ

The most amazing...

...thing I've achieved in seven years of my freelancing career is managing to sustain a 100% customer return rate.


  • Freelance Blockchain Developer

    2021 - PRESENT
    Toptal Client
    • Developed a front-runner trading bot for a private investor with Solidity and Node.js.
    • Handled different SSI projects and helped design a new product from the beginning.
    • Constructed a payment gateway to integrate an existing payment platform with the Ethereum network.
    Technologies: Node.js, Ethereum, Solidity, Hardhat, ERC20, ERC721, MongoDB, PostgreSQL, Hyperledger Indy, Hyperledger Aries, Truffle, Blockchain, Smart Contracts, Ethereum Smart Contracts, Cryptocurrency, Python, Ethers.js, Web3.js, Git, Non-fungible Tokens (NFT), Express.js, REST APIs, TypeScript, TypeORM, Bitcoin, Decentralized Finance (DeFi)
  • Blockchain Developer

    2019 - 2021
    Harvey Nash
    • Developed an SSI project from scratch, participating in all phases since its conception and architecture implementation with Hyperledger Indy and Aries to exchange master data and industrial certificates between two big German companies.
    • Set up an agile mindset while working with conservative customers.
    • Implemented a price and order negotiation system on Corda for low-trust and volatile price businesses.
    Technologies: Java, Kotlin, Corda, Solidity, PostgreSQL, Spring Boot, MongoDB, Hyperledger Indy, Hyperledger Aries, Self-sovereign Identity (SSI), Prototyping, Software Architecture, Zero-knowledge Proofs, Ethereum, JavaScript, React, Web3.js, Distributed Ledgers, Architecture, R3 Corda, Node.js, ERC721, Smart Contracts, Ethereum Smart Contracts, REST APIs, Express.js, TypeORM, TypeScript, DevOps, Back-end, DB, Bitcoin
  • DLT Software Developer

    2018 - 2019
    The Debtvision
    • Contributed to a successful startup in its founding era.
    • Designed and developed a decentralized system to manage multi-million euro loans and documents related to the loan.
    • Oversaw external development and consulted the team on security issues.
    Technologies: Corda, Kotlin, Spring Boot, Digital Signatures, Software Architecture, PostgreSQL, Decentralized Applications, System Architecture, Product Design, React, Distributed Ledgers, Distributed Ledger Technology, R3 Corda, SQL, Express.js, REST APIs
  • Software Engineer

    2016 - 2018
    Harvey Nash
    • Developed a loan transaction platform between Daimler AG and LBBW on the Proof of Authority (PoA) Ethereum network.
    • Developed an environmental reward coin for Mercedes-Benz cars and a mobile application with a gamification aspect.
    • Contributed to establishing a new team, forming an outstanding team culture, and hiring new colleagues.
    Technologies: Solidity, Corda, Java, PostgreSQL, AngularJS, Android, Web3.js, Ganache, Hyperledger Sawtooth, REST, Ethereum Smart Contracts, Blockchain, Prototyping, Software Architecture, Requirements Analysis, ERC20, Ethereum, JavaScript, R3 Corda, SQL, Node.js, Smart Contracts, Agile, Bitcoin
  • Co-founder | Software Developer

    2010 - 2016
    Bal Yazilim Limited
    • Managed a team of six. The team was first formed with junior developers, but after some time and long training sessions, I was proud of the team and their capacity.
    • Collaborated with a large number of different customers for over seven years, with a 100% return rate among customers.
    • Led the core team on an online training platform for the biggest GSM operator in Turkey.
    Technologies: PHP 5, Java, JBoss Seam, Spring, Oracle 11g, MySQL, Android, Team Leadership, Software Architecture, Requirements Analysis, Customer Success, Startups, JavaScript, SQL, Node.js


  • Debtvision DLT Schuldscheindarlehen Platform

    A Corda-based application designed to improve loan processes in a multi-investor environment. Digitalized all processes and integrated qualified digital signatures, and reduced the process's timeline from weeks to a couple of days (technically minutes).


  • Languages

    Java, Kotlin, Solidity, JavaScript, SQL, TypeScript, PHP 5, Python
  • Frameworks

    Truffle, Spring Boot, Angular, AngularJS, JBoss Seam, Spring, Express.js
  • Libraries/APIs

    Web3.js, Node.js, REST APIs
  • Tools

    IntelliJ, Ganache, Helm, Hyperledger Indy, Gradle, GitLab CI/CD, Git, GitHub
  • Paradigms

    Agile, REST, Requirements Analysis, DevOps
  • Platforms

    MacOS, Corda, Kubernetes, Blockchain, Ethereum, Docker, R3 Corda, Hyperledger, Android, Hyperledger Sawtooth, Rancher
  • Storage

    PostgreSQL, MongoDB, Oracle 11g, MySQL, DB
  • Other

    Software Engineering, IT Project Management, Software Architecture, Smart Contracts, Ethereum Smart Contracts, Cryptocurrency, Self-sovereign Identity (SSI), Team Management, Team Leadership, DApps, Prototyping, System Architecture, Customer Success, ERC20, Distributed Ledgers, Distributed Ledger Technology, Architecture, Hyperledger Aries, Digital Signatures, Zero-knowledge Proofs, Hardhat, ERC721, TypeORM, Decentralized Applications, Product Design, Startups, Ethers.js, Non-fungible Tokens (NFT), Back-end, Bitcoin, Decentralized Finance (DeFi)


  • Bachelor of Science Degree in Computer Science and Engineering
    2005 - 2014
    Yıldız Technical University - Istanbul, Turkey


  • Corda Certified Developer
  • Professional Scrum Master 1
    JUNE 2014 - PRESENT

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