Common Prefix

Meet the team

We are a small team of scientists and software engineers offering blockchain science consulting services.

Shresth Agrawal
Shresth Agrawal

Shresth Agrawal

smart contract development, auditing, algorithms

Shresth is a smart contract and backend developer. He holds a bachelor degree in Computer Science from Jacobs University Bremen. He has experience building efficient and secure algorithms, protocols, and smart contracts for several DeFi protocols. Previously, he worked at ParaSwap where he was responsible for developing a significant part of the core aggregation algorithm. He is interested in Cryptography, Security, Consensus Protocols, Decentralised Finance, and Ethereum. One of Shresth’s research highlights is the paper Proofs of Proof-of-Stake with Sublinear Complexity.

Dr. Zeta Avarikioti
Dr. Zeta Avarikioti

Dr. Zeta Avarikioti

distributed systems, scaling blockchains, cryptoeconomic incentive analysis

Zeta is an upcoming Assistant Professor at the Technical University of Vienna (TU Wien) in Austria. She is currently a post-doctoral blockchain researcher at TU Wien working with professor Matteo Maffei. She graduated with a PhD from ETH Zürich, advised by Roger Wattenhofer, and holds an engineering degree from the National Technical University of Athens and a masters degree from National Kapodistian University of Athens. She specializes in distributed systems, scaling blockchains via sharding and channels, and the analysis of cryptoeconomic incentives. Among other venues, she has published in Financial Crypto, AFT and SODA. Highlights of her research include the papers BRICK: Asynchronous Payment Channels, Cerberus Channels: Incentivizing Watchtowers for Bitcoin, and Divide and Scale: Formalization of Distributed Ledger Sharding Protocols.

Dr. Pyrros Chaidos
Dr. Pyrros Chaidos

Dr. Pyrros Chaidos

zero-knowledge proofs, voting

Pyrros is a post-doctoral blockchain researcher at the University of Athens. He holds a PhD from the University College of London, advised by Jens Groth and Allan Sikk, an MSc in Information Security from the University College of London, an MSc in Theoretical Computer Science from the University of Athens, and a BA in Mathematics from the University of Athens. He specializes in zero knowledge proof systems, with applications on proof-of-stake blockchains and voting in particular. Among other venues, he has published in EUROCRYPT, ACM CCS, PKC, ESORICS, and the Journal of Cryptology. Highlights of his research include the papers Mithril: Stake-based Threshold Multisignatures, Efficient Zero-Knowledge Arguments for Arithmetic Circuits in the Discrete Log Setting, and Foundations of Fully Dynamic Group Signatures.

Prof. Bernardo David
Prof. Bernardo David

Prof. Bernardo David

multiparty computation, consensus

Bernardo David is an Associate Professor at the IT University of Copenhagen, working on cryptographic protocols for multiparty computation and blockchain consensus/applications with the support of Concordium Foundation, Independent Research Fund Denmark and Protocol Labs research grants. He holds a Ph.D. in Computer Science from Aarhus University, under the supervision of Ivan Damgård and Jesper Buus Nielsen, and was previously an Assistant Professor at the Tokyo Institute of Technology, where his work was supported by a JSPS research grant. Bernardo’s research has been published as over 30 articles in scientific journals and conferences. Among his main contributions is the first provably secure protocol for proof-of-stake blockchains. Besides academic activities, he has been a consultant for a number of industry projects on blockchains and information security, having served as scientific advisor to Cardano and Concordium.

Nikolaos Kamarinakis
Nikolaos Kamarinakis

Nikolaos Kamarinakis

smart contract development, testing, software engineering, offensive security

Nikolas is a software engineer based in Athens, Greece and Maryland, USA. He holds a Bachelor’s degree in Computer Science with a minor in Cybersecurity from the University of Maryland. He has multiple years of experience in full-stack software engineering and open-source development, as well as some experience in offensive security. Nikolas is currently focused on smart contract development at Common Prefix.

Dr. Dimitris Karakostas
Dr. Dimitris Karakostas

Dr. Dimitris Karakostas

cryptocurrency wallets, macroeconomics, checkpointing

Dimitris is a post-doctoral blockchain researcher at the University of Edinburgh where he works with professor Aggelos Kiayias. He holds a PhD from the University of Edinburgh, advised by Aggelos Kiayias, and an Electrical and Computer Engineering degree from the National Technical University of Athens. He specializes in cryptocurrency wallets and macroeconomics, as well as chain checkpointing. Among other venues, he has published in Financial Crypto and presented at Black Hat Europe and Asia. Highlights of his research include the papers A Formal Treatment of Hardware Wallets, Cryptocurrency Egalitarianism: A Quantitative Approach, and Securing Proof-of-Work Ledgers via Checkpointing.

Haris Karavasilis
Haris Karavasilis

Haris Karavasilis

business development, project management, quantitative finance, risk management

Haris works on the business side of things at Common Prefix. His background includes roles at Amazon and Piraeus Bank, where he gained valuable experience in operations, finance and risk management. He holds a Master's degree in Quantitative Finance and Risk Management from Bocconi University and an Electrical & Electronic Engineering Bachelor's degree from the University of Manchester. At Common Prefix, he contributes to both business development and project management, aiming to improve operational and financial efficiency.

Dimitris Lamprinos
Dimitris Lamprinos

Dimitris Lamprinos

smart contract development, large scale system design, software engineering, consensus, DevOps

Dimitris is a software engineer based in Athens, Greece. He holds a Bachelor's degree in Computer Science from Aristotle University of Thessaloniki. At Common Prefix, he is a software engineer focusing on Solidity smart contracts and basic consensus development. Besides his web3 expertise, Dimitris has significant experience in building and scaling web applications. Before joining Common Prefix, he worked at Geekbot, one of the most popular Slack bots, and Amondo, a social media startup with over a million users, where he led the infrastructure team.

Themis Papameletiou
Themis Papameletiou

Themis Papameletiou

smart contract development, testing, software engineering, algorithmic trading, rockets

Themis is a software engineer based in Athens. He has significant experience developing software for a variety of projects such as web applications, algorithmic traders and rockets. He is pursuing a Master’s degree in Electrical and Computer Engineering from the National Technical University of Athens and has also completed internships at Google and at the European Space Agency. Currently, he is focused on smart contract development and testing.

Giulia Scaffino
Giulia Scaffino

Giulia Scaffino

scaling blockchains, blockchain interoperability, cryptoeconomic incentive analysis

Giulia is a doctoral blockchain researcher at the Technical University of Vienna (TU Wien), working in the Security and Privacy group with Prof. Matteo Maffei. She holds a Master's degree in Nuclear Physics from the University of Pavia, Italy, and she has worked as a Salesforce developer at Deloitte Digital in Milan. She specializes in blockchain interoperability and scalability protocols, light clients, layer-2 solutions, and crypto-economic incentives. Among other venues, she has published in the USENIX Security Symposium.

Semeli Spanou
Semeli Spanou

Semeli Spanou

operations, logistics, biotech, data analytics

Semeli is a member of the Operations team at Common Prefix, where she collaborates with a diverse range of stakeholders to drive operational efficiency and effectiveness. She holds a Master's degree in Biotechnology, from the Agricultural University of Athens, with a focus on bioinformatics and data analysis. Semeli's organisational and analytical skills contribute to enhancing operational procedures, streamline reporting, and strengthening our logistics management.

Dr. Orfeas Stefanos Thyfronitis Litos
Dr. Orfeas Stefanos Thyfronitis Litos

Dr. Orfeas Stefanos Thyfronitis Litos

software engineering, payment channels, voting, cryptoeconomic incentive analysis

Orfeas is currently a research associate at Imperial College London. He obtained his PhD in Cryptography and Blockchains at the University of Edinburgh in 2021, under the supervision of Aggelos Kiayias. He has worked on building and analyzing decentralized applications on blockchains, layer-2 protocols, payment channels, and voting solutions, all through formal cryptographic methods. Among others, he has formally analyzed the security of the Lightning Network and created a novel virtual payment channel construction. He is knowledgeable in software engineering and secure architecture. His interests further include formal verification, incentive analysis, and provable security.

Apostolos Tzinas
Apostolos Tzinas

Apostolos Tzinas

smart contract development, algorithms, software engineering

Apostolos is a smart contract software engineer. He is pursuing a joint Bachelor and Master’s degree in Electrical and Computer Engineering at the National Technical University of Athens. Apostolos has extensive front-end software engineering experience working at Maya Insights, as well as at NutriDice, where he took on a full-stack engineering role. He has worked with numerous programming languages and technical stacks. Apostolos’s research highlights include The Principal–Agent Problem in Liquid Staking, published in Financial Cryptography 2023’s 7th Workshop on Trusted Smart Contracts (WTSC), and On-Chain Timestamps Are Accurate.

Dr. Dionysis Zindros
Dr. Dionysis Zindros

Dr. Dionysis Zindros

scaling blockchains, light clients, fast bootstrapping, algorithms, software engineering

Dionysis is a post-doctoral blockchain researcher at Stanford University. He holds a PhD from the University of Athens, advised by Aggelos Kiayias, and an Electrical and Computer Engineering degree from the National Technical University of Athens. He specializes in blockchain scalability via light clients and fast bootstrapping. Among other venues he has published in IEEE S&P (Oakland), ACM CCS, ESORICS, and Financial Crypto, and presented at Black Hat Europe and Asia. Highlights of his research include the papers Non-Interactive Proofs of Proof-of-Work, Proof-of-Stake Sidechains, and Proof-of-Work Sidechains.