Senior Blockchain developer
2018 - PRESENT6fusion (via Toptal)- Wrote software in Go which interacts with blockchain platform.
- Worked with Quorum platform.
- Used Docker and Kubernetes for deployments.
Technologies: Go, Ethereum, Quorum, SoliditySolidity/Blockchain Expert with Go Experience
2018 - PRESENTFractal Blockchain (via Toptal)- Contributed to software written in Go which interacts with Ethereum nodes (with geth nodes specifically).
- Reviewed and improved smart contracts written in Solidity.
- Reviewed and improved software interacting with the Bitcoin network.
Technologies: Blockchains, Solidity, Ethereum, Bitcoin, GoSoftware Engineer
2018 - PRESENTEvernym- Developed a secure crypto-wallet intended to be used for Hyperledger Indy.
- Supported the Indy-SDK project.
- Created proprietary software solving SSI-related problems on top of Hyperledger Indy.
- Bulit a system of pluggable crypto-wallet storage back-ends which allows for enterprise-scale wallets.
Technologies: Python, Rust, HyperledgerSoftware Engineer
2016 - 2018TeleSign- Developed the Number Discovery Platform using Python and Gevent.
- Extended the PhoneID product written in Python and Bottle.
- Created a URL-shortening service using Python and Flask.
- Built a Number Deactivation product using Python.
Technologies: Python, Gevent, Bottle, FlaskWeb Developer
2015 - 2016BEST- Wrote an internal HR application using JSP.
- Refactored an internal voting system written in a custom in-house framework.
- Supported and extended an internal forum written in JSP.
Technologies: Python, JavaWeb Developer
2012 - 2016Self-employed- Wrote a web crawler and scraper using Python and Beautiful Soup.
- Developed a custom content manager application back-end using Django.
- Created web microservices using Python.
Technologies: Python, Flask, Django, Pyramid, Java, JSP, Beautiful Soup
Janko Krstic
Python Developer in Belgrade, Serbia
Member since June 5, 2018
Janko is a software engineer who specializes in Blockchain with a focus on Bitcoin, Ethereum, and Hyperledger (Fabric, Indy). He is always looking to increase his knowledge and expertise with a willingness to dive into the unknown. Janko has most recently worked on applying modern distributed systems, cryptography, and blockchain theory to solving SSI-related problems.
Janko is now available for hire
Portfolio
- 6fusion (via Toptal)Go, Ethereum, Quorum, Solidity
- Fractal Blockchain (via Toptal)Blockchains, Solidity, Ethereum, Bitcoin, Go
- EvernymPython, Rust, Hyperledger
Experience
- Python, 8 years
- Blockchain, 3 years
- Go, 3 years
- Rust, 1 year
- Solidity, 1 year
- IPFS, 1 year
Availability
Part-time
Preferred Environment
Linux, Python-Go-Rust-Erlang, Git
The most amazing...
...project I've worked on was a secure, enterprise-level crypto wallet with tagging features for searching and filtering encrypted records.
Employment
Experience
- Hyperledger Indy Crypto Wallet (Development)https://github.com/hyperledger/indy-sdk
Designed and developed a crypto wallet used in Hyperledger Indy.
Some of the features that distinguish this wallet:
1. mechanism for searching through encrypted entities using tags
2. multiple encryption keys using Elliptic Curve Cryptography
3. pluggable storage system supporting enterprise-scale crypto wallets - Identity Solution for Red Cross Refugees on Top of Hyperledger Indy (Development)
Part of the team that designed and developed a solution for solving identity problems for the refugees in Red Cross centers. This was a part of Blockchaingers 2018 Hackathon, which was held in Groningen, Netherlands
- Multichain Tracker (Blockchain Data Tracker and Aggregator) (Development)
This project allowed the user to track through a dashboard different blockchains (and possibly even private sidechains if they exposed correct APIs), and be able to both look at the current data, as well as track data (hashes) across several blockchains.
It integrated with most common blockchains (Bitcoin, Ethereum, etc.) through their APIs, and fed data through web sockets to a front-end dashboard. - Reward System on Top of Ethereum Blockchain (Development)
Developed a part of a platform intended for rewarding loyal users of the platform and provide gamification, using Ethereum.
- Pharmachain (Provenance and Supply Chain Blockchain) (Development)
Blockchain for tracking provenance and ownership transfers of pharmaceutical supplies. It was intended to function on an international level and enable easier tracking of transfers across international borders, to prevent scam, and track defects and inappropriate batches.
- Website and Web App Used in BEST (Development)https://best.eu.org/index.jsp
Redesigned an old website into a current, modern version.
Refactored and extended the internal application. - Number Discovery Platform (Development)https://www.telesign.com/products/sms-api/
One of the key components of the SMS platform used to discover the best routes and providers for delivering an SMS.
- Phone ID Service (Development)https://www.telesign.com/products/phone-id/
Developed and extended existing features for a Phone ID service. It is a service intended to provide sophisticated information for phone numbers.
Skills
Languages
Go, Python, Solidity, Rust, JavaScript, JavaPlatforms
Blockchain, Kubernetes, Docker, Hyperledger Fabric, Ethereum, Hedera HashgraphOther
Distributed Systems, Ethereum Smart Contracts, Smart Contracts, IPFS, Bitcoin, Peer-to-peer Networking, Hashgraph Technology, EOSIO, EOS, Quorum, CryptographyTools
Hyperledger Indy, Stellar SDKParadigms
Concurrent Programming, Agile, Functional ProgrammingStorage
Relational Databases, Cassandra, BigchainDBFrameworks
Flask, Django
Education
- Bachelor's degree in Software Engineering2012 - 2016University in Belgrade - Belgrade, Serbia
