Dimitris Karakostas

Professional Experience

Oct 2021 - Present | Researcher, Common Prefix (Remote)
Offering consulting services on the theory and practice of distributed ledgers.
Dec 2021 - Nov 2024 | Research Associate, University of Edinburgh
Contributed to the Edinburgh Decentralization Index; researched blockchain decentralization, mitigations of long‑range attacks, and Proof‑of‑Stake auditability.
Nov 2017 - Aug 2021 | Researcher, IOHK (Remote)
Researched PoS settlement layers, stake delegation design in Cardano, and 51% attack mitigations.
Feb 2016 - Mar 2017 | Student Researcher, CryptoSec Lab, University of Athens
Investigated compression‑based side‑channel attacks; developed Rupture and CTX frameworks.
Apr 2015 - Feb 2016 | Working Student, Nokia (Athens)
Built CI systems, dashboards, and fault predictability tools to enhance code health.

Education

2017-2021: PhD, Computer Science, University of Edinburgh, UK.
Thesis: Digital Asset Management via Distributed Ledgers (Advisor: Aggelos Kiayias)
2010-2016: MEng Electrical & Computer Engineering, NTUA, Greece.
Thesis: Probabilistic Attacks against Compressed Encrypted Protocols (Advisor: Aris Pagourtzis)

Teaching

University Teacher: Sep 2021 – Dec 2021, Sep 2022 – Dec 2022: Blockchains and Distributed Ledgers, University of Edinburgh (5 ECTS, SCQF 11). Nominated Teacher of the Year 2023.
Teaching Assistant: 2018–2020: Blockchains and Distributed Ledgers, University of Edinburgh; 2015: Cryptography, NTUA, Greece.

Publications & Manuscripts

Preprint: Optimal Reward Allocation via Proportional Splitting (Lukas Aumayr, Zeta Avarikioti, Dimitris Karakostas, Karl Kreder, Shreekara Shastry)
ACNS ’25 SoK: Measuring Blockchain Decentralization (Christina Ovezik, Dimitris Karakostas, Mary Milad, Aggelos Kiayias, Daniel W. Woods)
ACM CCS ’24: Blockchain Bribing Attacks and Efficacy of Counterincentives (Dimitris Karakostas, Aggelos Kiayias, Thomas Zacharias)
CANS ’24: Scalable and Lightweight State-Channel Audits (Christian Badertscher, Maxim Jourenko, Dimitris Karakostas, Mario Larangeira)
CAAW@WWW ’24: Statistical Confidence in PoW Mining Estimates (Mary Milad, Christina Ovezik, Dimitris Karakostas, Daniel W. Woods)
Springer ’24: Security of Delegated PoS Wallets & Stake Pools (Dimitris Karakostas, Mario Larangeira)
FC ’24 SoK: A Stratified Approach to Blockchain Decentralization (Christina Ovezik, Dimitris Karakostas, Aggelos Kiayias)
ACM AFT ’22: Blockchain Nash Dynamics & Compliance (Dimitris Karakostas, Aggelos Kiayias, Thomas Zacharias)
ACM MobiHoc ’22: Optimal Bootstrapping of PoW Blockchains (Ranvir Rana, Dimitris Karakostas, Sreeram Kannan, Aggelos Kiayias, Pramod Viswanath)
CBT@ESORICS ’21: Filling the Tax Gap via Programmable Money (Dimitris Karakostas, Aggelos Kiayias)
ESORICS ’21: Conclave: A Collective Stake Pool Protocol (Dimitris Karakostas, Aggelos Kiayias, Mario Larangeira)
IEEE ICBC ’21: Securing PoW Ledgers via Checkpointing (Dimitris Karakostas, Aggelos Kiayias)
FC ’21: Efficient State Management in Ledgers (Dimitris Karakostas, Nikos Karayannidis, Aggelos Kiayias)
SCN ’20: Account Management in PoS Ledgers (Dimitris Karakostas, Aggelos Kiayias, Mario Larangeira)
TOKENOMICS ’19: Cryptocurrency Egalitarianism (Dimitris Karakostas, Aggelos Kiayias, Christos Nasikas, Dionysis Zindros)
FC ’19: A Formal Treatment of Hardware Wallets (Myrto Arapinis, Andriana Gkaniatsou, Dimitris Karakostas, Aggelos Kiayias)
BH EU ’16: CTX: Eliminating BREACH with Context Hiding (Dimitris Karakostas, Aggelos Kiayias, Eva Sarafianou, Dionysis Zindros)
BH ASIA ’16: Practical New Developments on BREACH (Dimitris Karakostas, Dionysis Zindros)

Selected Invited Talks

AtheCrypt ’24: EDI - Measuring Blockchain Decentralization
FOCODILE ’21: Efficient State Management in Ledgers
Theory & Practice of Blockchains ’20: Checkpointing PoW Ledgers
AtheCrypt ’20: PoW Ledger Checkpointing
CESC ’19: Cryptocurrency Egalitarianism
BSides Athens ’17: Attacking IPv6 - Bettercap Patch
AtheCrypt ’17: CTX - Context Hiding
BSides Athens ’16: Rupture - Cryptanalysis Automation
RWC ’16: New BREACH Developments
AtheCrypt ’16: Probabilistic Attacks on Compressed Protocols

Academic Service

Program Committee: CANS ’24; MARBLE ’22-25; CIFRIS ’23; TOKENOMICS ’22-23; BLOCKCHAIN ’22
Subreviewer: Crypto ’22; IEEE ICDCS ’22; Euro S&P ’21; ACM AFT ’20–21; FC ’19/’21; ACM CCS ’19–20; IEEE S&B ’20; IEEE S&P ’19; PENCIL ’19; PKC ’18; IEEE Blockchain ’18
Journal Reviewer: JCSS ’23; IEEE TDSC ’19/’20
Local Organizing: PKC ’20

Skills

Languages: Greek (Native); English (Proficient); German (Intermediate)
Programming & Tools: Python; JavaScript; Solidity; Git; Vim; HTML5/CSS3; Django; Flask; Node.js; React; TLS; REST