Research Scientist

• Datometry. (Nov. 2019 - present) - Designing and developing features for a data virtualization technology, enabling applicationswritten for on-premise database systems to run on cloud data warehouses, without application code changes.

Research Assistant

• Brandeis University (2013 - 2019) - Designed and developed Retrospective Query Language (RQL), a declarative extension to SQL to provide efficient across time computations on data store snapshots.

• ICS-FORTH (2010 - 2013) - Participated in EU-funded projects in areas of System Security, File Systems and Distributed Systems. Designed and developed prototype systems, all described in peer-reviewed articles.

Teaching Assistant

• Brandeis University:  COSI 31A - Computer Systems Structure and Organization (Fall 2013), COSI 147A - Distributed Systems (Spring 2014, Spring 2018), COSI 131A - Operating Systems (Fall 2014, Fall 2015, Fall 2016, Fall 2017), COSI 12B - Advanced Programming Techniques (Spring 2015), COSI 146A - Principles of Computer System Design (Spring 2017)

• University of Crete:  TEM 101 - Introduction of Computer Science (Fall 2007, Fall 2008, Fall 2009), M 206 - Introduction of Computer Science (Spring 2009), CS 345 - Operating Systems (Fall 2010, Fall 2011, Fall 2012), CS 380 - Algorithms and Complexity (Spring 2011), CS 457 - Introduction to Secure Systems (Spring 2012), CS 455 - Network Attacks and Defense Techniques Laboratory (Spring 2013)

Talks

• When you have to make it faster
  Nikos Tsikoudis, and Marc Sugiyama
  Code BEAM America 2021 (Youtube video) (slides)

• Adaptive Real-time Virtualization of Legacy ETL Pipelines in Cloud Data Warehouses
  Nikos Tsikoudis
  18th Hellenic Data Management Symposium (HDMS) 2024

Conference Publications

• How Global Retailer ADEO Migrated to Google BigQuery with Database Virtualization

Ehab Abdelhamid, Amirhossein Aleyasen, Michael Duller, Eric Foratier, Vincent Fruleux, Mirella Katch, Gourab Mitra, Rima Mutreja, Jozsef Patvarczki, Matthew Pope, Nikos Tsikoudis, Florian M. Waas

In Proceedings of 2023 IEEE International Conference on Big Data (BigData) (Publisher's site)

• Adaptive Real-time Virtualization of Legacy ETL Pipelines in Cloud Data Warehouses
  Ehab Abdelhamid, Nikos Tsikoudis, Michael Duller, Marc Sugiyama, Nicholas E. Marino, and Florian M. Waas
  In Proceedings of the 26th International Conference on Extending Database Technology (EDBT), 2023 (PDF)

• RID: Deduplicating Snapshot Computations
  Nikos Tsikoudis, and Liuba Shrira
  In Proceedings of the 2020 ACM SIGMOD International Conference on Management of Data (SIGMOD), 2020 (Publisher's site) (Youtube video)

• RQL: Retrospective Computations over Snapshot Sets
  Nikos Tsikoudis, Liube Shrira, and Sara Cohen
  In Proceedings of the 21st International Conference on Extending Database Technology (EDBT), 2018. (PDF)

• Scalability of Replicated Metadata Services in Distributed File Systems
  Dimokritos Stamatakis, Nikos Tsikoudis, Ourania Smyrnaki, and Kostas Magoutis
  In Proceedings of the 12th IFIP International Conference on Distributed Applications and Interoperable Systems (DAIS), 2012 (PDF)

• Adapting Data-Intensive Workloads to Generic Allocation Policies in Cloud Infrastructures
  Giannis Kitsos, Antonis Papaioannou, Nikos Tsikoudis, and Kostas Magoutis (Joint First Author)
  In Proceedings of the IEEE/IFIP Network Operations and Management Symposium (NOMS), 2012 (PDF)

Journal Publications

• A General-Purpose Architecture for Replicated Metadata Services in Distributed File Systems
  Dimokritos Stamatakis, Nikos Tsikoudis, Eirini Micheli, and Kostas Magoutis
  In IEEE Transactions on Parallel and Distributed Systems (TPDS), 28(10): 2747-2759, 2017 (Publisher's site) (accepted version)

• LEoNIDS: a Low-latency and Energy-efficient Network-level Intrusion Detection System
  Nikos Tsikoudis, Antonis Papadogiannakis, and Evangelos P. Markatos
  In IEEE Transactions on Emerging Topics in Computing (TETC), 4(1): 142-155, 2016 (PDF)

Workshop Publications

• Troubleshooting the performance of a large Erlang system
  Nikos Tsikoudis, and Marc Sugiyama.
  In Proceedings of the 21st ACM SIGPLAN International Workshop on Erlang September 2022 (Erlang), 2022 (PDF) (Youtube video)

Posters

• RQL: Retrospective Query Language
  Nikos Tsikoudis, and Liuba Shrira
  North East Database Day (NEDB Day), 2016 (PDF).

Theses

• Retrospective Computations over Sets of Snapshots: Design, Implementation and Optimization.  Brandeis University, February 2020 (Publisher's site)  

• LEoNIDS: a Low-latency and Energy-efficient Network Intrusion Detection System. University of Crete, June 2013 (PDF) (slides)

• Kernel support for efficient per-flow selective packet discarding. University of Crete, June 2010

Information about my publications is also available online at DBLP, Google Scholar, and ResearchGate.

Ph.D in Computer Science

Brandeis University, Computer Science Department (September 2013 - February 2020) 

Thesis: Retrospective Computations over Sets of Snapshots: Design, Implementation and Optimization

M.A. in Computer Science

Brandeis University, Computer Science Department (September 2013 - December 2016)

GPA: 3.963/4.0

Selected Graduate Courses Attended: COSI 130A - Networked Information Systems, COSI 147A - Distributed Systems, COSI 146A - Principles of Computer System Design, COSI 180A - Algorithms, COSI 227B - Advanced Topics in Database Systems, COSI 129A - Introduction to Big Data Analysis

M.Sc. in Computer Science

University of Crete, Computer Science Department (September 2010 - June 2013)

GPA: 9.2/10.0

Thesis: LEoNIDS: a Low-latency and Energy-efficient Network Intrusion Detection System

Selected Graduate Courses Attended: CS 557 - Secure Systems, CS 460 - Database Management Systems, CS 556 - Distributed Systems, CS 590.45 - Modern Topics in Scalable Storage Systems, CS 559 - Infrastructure Technologies for Large-Scale Service-Oriented Systems

B.Sc. in Computer Science

University of Crete, Computer Science Department (September 2005 - September 2010)

GPA: 7.72/10.0

Thesis: Kernel support for efficient per-flow selective packet discarding

• Gerondelis Foundation, Inc. Grant for Academic Excellence (2014)

• ICS-FORTH Fellowship to conduct graduate research (September 2010 - June 2013)

• Certificate of the Gold Prize of the malware-analysis competition at the 7th International Workshop on Security (IWSEC 2012), in Fukuoka, Japan.