Next Meetup

Ethereum Plasma and Bitcoin Scripting
First an announcement: On 19-20 of November the next Voxxed Days developer conference will take place in Thessaloniki! This is a very successful and high-profile conference for developers and is taking place at our home town! You will find more information at They were kind enough to offer free tickets for the members of our meetup. During the break we will make a draw and two lucky members will be able to attend the conference for free. The agenda for the meetup is: 19.00 - 20.00 Introduction to Plasma for Blockchain Scalability — Georgios Konstantopoulos 20.00 - 20.15 Break 20.15 - 21.15 Introduction to Bitcoin Scripting — Kostas Karasavvas 21.15 - 21.30 Discussion / networking / end Abstracts: - Introduction to Plasma for Blockchain Scalability Plasma is a technique which is used to increase Ethereum transaction throughput, while maintaining network decentralization and security. We focus on the variant of Plasma called Plasma Cash, which allows for highly performant sidechains in production, today. We discuss Plasma Exits and Challenges as well as explore the User Interface choices for Plasma Apps. We go over the challenges encountered during the development and final implementation of a Plasma chain and contract. The presentation will highlight the advantages and disadvantages of using Plasma Cash, as well as practical examples of Plasma for Non Fungible Tokens and gaming. Finally, we'll talk about edge-cases such as griefing attacks, and future work towards making Plasma implementations more efficient, such as fast exits through liquidity providers, coin checkpointing through Plasma XT and arbitrary coin denominations through Plasma Debit. The audience is expected to walk away with a detailed understanding of how Plasma Chains should be built as well as the inner workings of the Plasma Cash technique. More experienced individuals who understand but are not following Plasma actively are expected to walk away with an overview of the current status of Plasma research and development, and motivated to tackle the existing open research problems. - Introduction to Bitcoin Scripting In this talk we go deeper into what constitutes a transaction and how scripting is used to lock bitcoins and later unlock them to spend them. We then provide several examples on how to create transactions by calling a node’s API or programmatically. Short Biographies of presenters: - Georgios is leading Plasma Research at Loom Network. He holds a MEng degree in Electrical & Computer Engineering. He previously worked at Honda where he did his thesis on metering and billing of energy with smart contracts. He has also worked as an independent smart contract auditor and pentester. He is interested in all-things-blockchain as well as cryptography, IoT, infosec and autonomous vehicles. - Dr. Konstantinos Karasavvas is a computer scientist with 20+ years of experience. He has worked in academic research in multi-agent systems and service-oriented architectures for about a decade and following that he worked in the industry as a software architect and engineer for several years and in several domains from bioinformatics to finance. Currently, and for the last 5 years, he is focused solely on blockchain technologies as a technical advisor. He is teaching and leading several research and development teams in both academia and industry. He is also an active member of local Bitcoin communities, organizing meetups and presenting in events. The environment is casual and there will be plenty of opportunities to learn and more importantly get to know each other. After the event everyone is welcome to one of the nearby cafeterias to get to know each other. Hope to see you there!


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