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Pavlos Polianidis, Software Developer in London, United Kingdom
Pavlos Polianidis

Software Developer in London, United Kingdom

Member since March 3, 2020
Pavlos is a technology lead and blockchain enthusiast who's worked for various companies across several industries including Sky UK, Lloyds Bank, and Deutsche Bank. He's been involved in the design and implementation of various web-based and blockchain systems and worked with diversified technology stacks. Pavlos has also successfully advised and engaged in several blockchain projects and worked with diverse technology stacks.
Pavlos is now available for hire
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Portfolio

Experience

Location

London, United Kingdom

Availability

Part-time

Preferred Environment

React, Web3.js, Ethereum, Solidity, Node.js, JavaScript, Blockchain, Rust, Elrond, near

The most amazing...

...project I've worked on was rebuilding the transaction page of Lloyds online banking in a short period of time.

Employment

  • Co-founder | CTO

    2018 - 2020
    Coincierge.io
    • Created the Transfer Checkpoint Layer (TCL) protocol: a blockchain compliance protocol that orchestrates and manages the compliance rules and verifies every token transaction between two parties.
    • Designed and developed the Concierge cabinet platform: a tokenization platform that manages and completely automates the lifecycle of security tokens.
    • Designed and implemented the token sale platform that provides full plug-and-play capabilities to support your company with raising funds through 50+ cryptocurrencies and fiat.
    • Created, designed, and delivered the Cabinet platform: a security token management platform that provides full compliance to companies with regards to managing traditional financial securities through the means of security tokens.
    • Managed a team of software engineers and organize the tasks to be delivered during each sprint.
    Technologies: Microservices, Bitcoin, Go, Vault, Solidity, Neo4j, Kubernetes, Apache Kafka, React, Node.js, JavaScript

  • Blockchain Tech Advisor

    2018 - 2019
    Ecoingot
    • Authored the technical part of the whitepaper—advising on all technical aspects needed to build a technology stack within the environmental tech and blockchain domain.
    • Designed the architecture and shaped the technical solution based on the initial ideas of the founders.
    • Represented the founders in talks with partners regarding the technical aspects of the company and the viability of the solution within the new blockchain domain.
    • Formed the product team that will deliver the project—hiring developers and designers based on their capabilities of delivering the solution that I had designed with the founders.
    • Represented the company and gave talks at international blockchain conferences.
    • Constantly evaluated the founders’ ideas and came up with a pragmatic solution that could work based on current technologies.
    Technologies: Blockchain

  • Blockchain Tech Advisor

    2018 - 2019
    Various World Technologies
    • Advised on all technical aspects needed to build a technology stack within the casino and gambling domain.
    • Educated founders with generic blockchain knowledge, e.g., basic cryptographic principles, crypto wallet management, multi-signature wallet, and more.
    • Constantly evaluated the founders’ ideas and came up with a pragmatic solution that could work based on current technologies.
    Technologies: JavaScript, Solidity, Cryptocurrency Wallets, Ethereum

  • Blockchain and Back-end Engineer

    2018 - 2019
    Lifelabs.io
    • Worked closely with the CTO—helping with blockchain-related solutions.
    • Implemented the entire notifications system that is used in the Life Wallet. This was a system that followed the microservices approach with several Node.js services communicating with each other through the choreography pattern.
    • Helped the junior members of the team with blockchain-related tasks.
    • Contributed to the initial steps of the DevOps infrastructure using Kubernetes.
    Technologies: Kubernetes, Stellar SDK, Hyperledger, Crypto, React Native, RabbitMQ, RxJS, Node.js, JavaScript

  • Blockchain and Smart Contract Engineer

    2018 - 2019
    Evident Proof
    • Created and deployed the EPT ERC20 smart contract to the Ethereum blockchain.
    • Created a set of smart contracts for the vesting plans of the company's investors.
    • Implemented a custom web-based Ethereum multi-signature wallet.
    • Responsible for deploying and distributing the EPT tokens the investors.
    • Deployed and managed the token vesting smart contracts that lock investors EPT holdings for a particular time and allows them to regularly release part of the entire fund.
    • Implemented a RESTful API that will engage with the EPT smart contract and perform the actions needed to support the system’s mechanics.
    • Created CLI tools for the company’s developers to allow them to easily interact with the multi-signature wallets, as well as token vesting and EPT smart contracts.
    Technologies: Node.js, Web3.js, Solidity, Ethereum

  • Blockchain Advisor | Smart Contract Engineer

    2018 - 2018
    The Coinlab
    • Conducted a requirements gathering session, including tokenomics and business use cases.
    • Authored ERC20 and crowdsale smart contracts using Ethereum and the Solidity language.
    • Worked with clients—helping them to design their BTC payment systems.
    • Created services around the Bitcoin ecosystem with a focus on multi-signature addresses and the secure storage of BTC funds.
    • Worked on proofs of concept (PoCs) for internal payment and bonus systems using decentralized ledger technologies.
    • Contributed to blockchain projects for companies like Audi, Bosh, and several companies in the area of real estate and invoice factoring.
    • Worked with technologies such as DApp, Web3j, Stellar, Lisk, Hyperledger, EOS, decentralized storage (IPFS, DOT protocol), and BIP32 wallets.
    Technologies: RabbitMQ, Apache Kafka, Firebase, Neo4j, React, Solidity, Stellar SDK, Ethereum, Bitcoin, Node.js, JavaScript

  • Technology Lead

    2016 - 2017
    Deutsche Bank
    • Served as a member of the digital asset management tea—shaping the digital transformation initiative by building tools and software.
    • Worked along with database traders—designing and implementing automated tools to interact and trade with various counterparties via different means, such as Symphony, Bloomberg, and so on.
    • Developed various proof-of-concept projects involving technologies such as machine learning classification algorithms for fraud detection and consortium blockchain (Hyperledger) interactions.
    • Developed and maintained the database JavaScript SDK, currently used by several development teams in Deutsche Bank.
    • Built cross-platform UI components that can be seamlessly integrated in React and React Native projects.
    Technologies: Hyperledger Fabric, Symphony, Bloomberg, Kubernetes, RxJS, React Native, React, Node.js, JavaScript

  • Lead JavaScript Engineer

    2016 - 2017
    Lloyds Bank
    • Worked on the LBG (Lloyds Bank Group) online banking system and the statements page of Lloyds, Halifax, and Bank of Scotland specifically.
    • Took ownership of the system from the previous team—ensuring a thorough knowledge transfer and collecting every piece of information needed to accomplish a smooth transition.
    • Found the system by interacting with members of multiple development teams across the Lloyds digital transformation department.
    • Analyzed the structure of the code and introduced several layers of abstractions (application, data flow/management, view, and so on) to make it easy to reason about.
    • Contributed to the reshaping of the ways of working in the team by advocating the use of agile principles and adapting small batch deliveries.
    • Set up an entirely new DevOps pipeline to accomplish continuous integration, continuous delivery, and continuous deployment.
    • Introduced strategies for code refactoring of the React-based application without pausing the implementation of new features.
    • Worked as part of the LBG front-end guild governing body responsible for modernizing, monitoring, and introducing good practices and patterns that are adapted across several teams within the LBG digital transformation department.
    • Contributed to the BuildIt front-end tribe initiative by giving various talks on topics like Angular 2, Elm, functional programming, advanced JavaScript async patterns, and Blockchain technologies.
    • Implemented a scaffolding tool that creates a boilerplate single-page application which teams in LBG can use to quickly bootstrap their projects.
    Technologies: Kubernetes, Jenkins, Node.js, JavaScript, React

  • Senior JavaScript Engineer

    2016 - 2016
    Sky UK
    • Worked as part of the NowTV editorial team, implementing a custom CMS for managing the NowTV content.
    • Contributed to the NowTV MEAN (Angular, MongoDB, and Node.js) stack.
    • Collaborated with the NowTV content editors on different features to achieve high user experience.
    • Gathered user requirements and created user stories.
    • Contributed to shared NPM packages used by several teams in Sky.
    • Fixed front-end and back-end performance issues mainly by improving the way AngularJS was used.
    • Pioneered the start of adopting new programming paradigms, e.g., reactive and functional.
    Technologies: RESTful Development, RESTful APIs, Node.js, MongoDB, AngularJS

  • Senior JavaScript Engineer

    2015 - 2016
    Football Radar
    • Worked in the football betting industry—implementing and maintaining highly performant real-time web-based systems.
    • Designed and implemented the SBS web application that has radically changed the way that football watchers collect data. This was a greenfield project with a duration of six months.
    • Designed and implemented the supervisor application; a highly performant real-time system that is capable of monitoring the way that watchers input their data.
    • Worked on the player model application that is being used by the watchers to collect data about individual players; it was an ongoing project that follows the microservices approach.
    • Introduced the idea of having a private NPM registry and created small reusable packages that can be shared among various projects.
    • Worked as the main contributor to the FRCSS project: a CSS framework following the ITCSS approach which we started with Harry Roberts (CSS Wizardry).
    • Maintained, fixed bugs and minimized the technical debt for various other projects.
    • Advocated for knowledge sharing sessions and organized the first JavaScript workshop for the development team.
    Technologies: Apache Kafka, Apache Thrift, Scala, RxJS, ECMAScript (ES6), React

  • Front-end Developer

    2014 - 2015
    Brand View
    • Designed and implemented the widgets for Thegrocer.co.uk.
    • Served as the lead front-end developer for an ongoing project to develop a data hub platform using object-oriented JavaScript, AngularJS, React, CSS3, and C# for APIs.
    • Worked as the lead front-end developer for a platform to automate product mapping using object-oriented JavaScript, asynchronous design patterns, and DOM manipulation (jQuery, Knockout.js).
    • Spearheaded the migration to a new front-end development workflow using the latest technologies and practices (Grunt, Gulp, Bower, WebPack, Browserify, and so on).
    • Created a timeline module (named after me) which represents a generic and customizable Gantt Chart; it was built with D3.js.
    • Used object-oriented JavaScript to create a charting framework: a wrapper around Highcharts.
    Technologies: Webpack, .NET, React, Node.js, JavaScript

  • Web Developer

    2012 - 2014
    Cirrus Logistics
    • Designed and implemented a set of features (site traffic) for the leading warehouse design and simulation tool, CLASS.
    • Designed and developed the security infrastructure of the company’s web-based applications using .NET WIF. It helped to win a deal with Chevron and Exxon Mobil.
    • Revamped an existing desktop app into a web-based application using Knockout.js, Durandal.js, D3.js, and object-oriented JavaScript.
    Technologies: D3.js, React, AngularJS, JavaScript, OAuth, Windows Presentation Foundation (WPF), .NET, C#

Experience

  • Security Tokenization Platform

    Tasks Accomplished:
    • Created the Transfer Checkpoint Layer (TCL) protocol: a blockchain compliance protocol that orchestrates and manages the compliance rules and verifies every token transaction between two parties. The TCL creates a dynamic and upgradeable layer of rules that define the validity of any security token ownership transaction.
    • Designed and developed the Concierge cabinet platform: a tokenization platform that manages and completely automates the lifecycle of security tokens. It utilizes an on-chain compliance and identity protocol that standardizes and automates how crypto-securities are created and transferred.

  • Vesting Smart Contracts

    Tasks Accomplished:
    • Implemented a custom web-based Ethereum multi-signature wallet.
    • Deployed and distributed the EPT tokens for the investors.
    • Deployed and managed the token vesting smart contracts that locked the investors' EPT holdings for a particular time and allowed them to regularly release part of the entire fund.
    • Created CLI tools for the company’s developers to allow them to easily interact with the multi-signature wallets, as well as, the token vesting and EPT smart contracts.

  • Crypto Wallet

    Tasks Accomplished:
    • Implemented the entire notifications system that is used in the Life Wallet. This was a system that followed the microservices approach with several Node.js services communicating with each other through the choreography pattern backed by a messaging queue.
    • Contributed to the initial steps of the DevOps infrastructure using Kubernetes.
    • Helped with the crypto wallet implementation.

Skills

  • Languages

    JavaScript, Solidity, C#, ECMAScript (ES6), Scala, Go, Rust, F#, Python

  • Frameworks

    React Native, Angular, .NET, Windows Presentation Foundation (WPF), AngularJS, Apache Thrift, Tendermint, Parity Polkadot

  • Libraries/APIs

    React, Node.js, Web3.js, React Redux, D3.js, RxJS

  • Platforms

    Blockchain, Apache Kafka, Kubernetes, Rancher, Docker, Hyperledger, Hyperledger Fabric, Firebase, Ethereum

  • Other

    Bitcoin, Cryptocurrency Wallets, Cryptocurrency APIs, ERC-20, Cryptocurrency Development, Cryptocurrency Payments, Smart Contracts, Ethereum Smart Contracts, Non-fungible Tokens (NFT), Cryptocurrency, Solana, RESTful APIs, OAuth, Symphony, Crypto, Cryptography, Elrond, near

  • Tools

    RabbitMQ, Webpack, Jenkins, Bloomberg, Stellar SDK, Vault

  • Storage

    Neo4j, MongoDB

  • Paradigms

    Microservices, RESTful Development

Education

  • Master of Science Degree with Distinction in Web Technology
    2011 - 2012
    University of Southampton - Southampton, UK
  • Bachelor of Science Degree with Distinction in Computer Science
    2006 - 2011
    Aristotle University of Thessaloniki - Thessaloniki, Greece

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