Stamatis Zampetakis

Profile photo
  • 61 Terrasse de l'Arche, 92000, Nanterre, France
  • +33 (0) 6 51 05 95 78

Carreer summary

Professional experience

Senior Software Engineer

Cloudera Paris, France
May 2020 - Present

R&D Engineer

TIBCO Paris, France
January 2016 - April 2020
  • Designed and implemented the first version of the SQL query processor of the system using Apache Calcite.
  • Coordinated groups of 3-4 engineers to improve (new features & bug fixes) the query processor.
  • Designed and implemented part of the new indexing framework of the system using Apache Lucene improving the scalability of the system by a factor of 10.
  • Participated in the prototyping of a multi-versioned ORM system based on JPA and Hibernate capable of handling millions of records and several thousand versions.
  • Resolved critical bugs in production involving race conditions and memory leaks.
  • Collaborated with the other teams (support, UI, CI) to address customer requests and improve the system.
  • Presented various R&D subjects in universities and conferences, promoting the company.
  • Participated in the recruitment proccess for selecting and hiring new engineers.

Post-doctoral researcher

INRIA Orsay, France
November 2015 - January 2016
  • Devised data integration techniques for applications relying on multiple data management systems (Postgres, MongoDB, AsterixDB, SparkSQL, Solr) to facilitate querying and improve performance, publishing papers in SIMGOD (A*) and ICDE (A*).
  • Assisted in the implementation of Estocada (a polystore system) by improving the query rewriting algorithm and prototyping the connectors for Redis, Spark, and Postgres.
  • Co-authored a book on cloud-based RDF data management, presenting and criticizing the most prominent aproaches in terms of storage, query processing, and reasoning.
  • Served as member of SIGMOD 2015 Reproducibility committee.

Doctoral researcher

INRIA Orsay, France
October 2012 - October 2015
  • Devised partitioning and query processing algorithms for distributed architectures emphasizing on RDF data management publishing 2 papers in ICDE (A*).
  • Designed and implemented CliqueSquare, a distributed system relying on Hadoop MapReduce/HDFS capable of answering queries 10x faster than the state-of-the-art; it features a query/plan parser, algebraic operators, a novel partitioner and query planner.
  • Devised indexes for cloud-based RDF data management systems examining performance/storage/monetary cost trade offs publishing the results in a book chapter.
  • Directed the implementation of RDF indexes in AMADA, a data management system for RDF/XML data relying on Amazon S3, EC2, DynamoDB, and SQS services.
  • Designed a system for semi-automatic fact-checking publishing a demo paper in SIGMOD (A*) and initiating a collaboration with Le Monde.
  • Designed and implemented FactMinder, a Chrome plugin for semi-automatic fact-checking relying on Javascript and JQuery.
  • Administrated the installations of Hadoop, Spark, Redis, Postgres, and Hive in a cluster of 10 nodes.
  • Organized the seminars of the LaHDAK team.
  • Reviewed numerous research papers for ESWC (A), SIGMOD (A*), and ICDE (A*) conferences.

Research assistant

INRIA Orsay, France
September 2010 - July 2011
  • Devised a novel data model, XR, for naturally representing documents (XML) with annotations (RDF) publishing a paper in VLDB Journal (A*).
  • Implemented a system prototype for XR by extending ViP2P, a P2P XML data management system implemented in Java, with RDF support and a bind join algorithm.
  • Designed and implemented in Java a customizable generator for RDF data, capable of generating millions of RDF triples in only a few seconds, which was used for benchmarking the XR system.

Research assistant

FORTH-ICS Heraklion, Greece
July 2008 - September 2010
  • Devised techniques for the visualization and exploration of RDF graphs, publishing a demo in ESWC (A) and a journal in JVLC (A).
  • Implemented some of the major features of StarLion, an RDF visualization application written in Java (relying on JGraph), such as smooth transitions, semi-automatic layout, plugin support, force indicators, node colouring, save/load layouts, undo/redo actions, image exporting ), which according to user studies greatly improved the usability of the tool.
  • Improved the performance of StarLion (through caching, better data structures, and smarter algorithms) reducing response time by a factor of 100.
  • Designed, implemented, and curated the Website of StarLion.

Teaching experience

Teaching assistant

Université de Paris-Sud Orsay, France
February 2014 - June 2016
Basic Principles of Object Oriented Design


PhD in Computer Science

Université de Paris-Sud Orsay, France
2012 - 2015

MSc in Computer Science

Université de Paris-Sud Orsay, France
University of Crete Heraklion, Greece
2009 - 2011
GPA 17.38/20 (2nd) with 105/90 course credits.

BSc in Computer Science

University of Crete Heraklion, Greece
2005 - 2009
GPA 8.01/10 (2nd) with 182/158 course credits.



  1. Java
  2. SQL
  3. JPQL
  5. C/C++
  6. Python
  7. XPath
  8. Bash
  9. PHP
  10. XQuery
  11. Prolog
  12. Verilog
  13. MIPS assembly


  1. HTML
  2. CSS
  3. TypeScript
  4. Javascript
  5. Angular
  6. jQuery

Data management

  1. Apache Calcite
  2. Apache Lucene
  3. Hibernate
  4. Apache Spark
  5. PostgreSQL
  6. Oracle Database
  7. Microsoft SQL Server
  8. H2 database
  9. Redis
  10. Berkeley DB
  11. BaseX


  • SVN
  • Git
  • Latex


  • Greek (Native)
  • English (Fluent)
  • French (Proficient)