Thomas S. Repantis

https://www.ninewhilenine.org                  thomas@ninewhilenine.org

INTERESTS
  Engineering leadership for highly-scalable, fault-tolerant, real-time, distributed systems. 

PROFESSIONAL EXPERIENCE
  Elastic, Platform Engineering, Somerville, MA, April 2021-Present
    Senior Manager of Engineering
    Leading the team that develops all distributed systems aspects of
    Elasticsearch, including cluster coordination and data
    replication.  Doubled the team's size in one year; currently 11 engineers. 
    Oversaw four promotions and four patent applications.  The team
    delivered traffic compression by more than 50%, a
    resource-sensitive shard allocator, and scalability improvements
    reducing out-of-memory errors 12-fold.  Updated the support
    escalation process across 10 Elasticsearch teams and more than 70
    engineers, reducing median response time by 36%, time investment
    by 276%, and stress by 84%.  Documented the responsibilities of
    Elasticsearch managers. Mentored close to half a dozen engineering
    managers.  

  Akamai Technologies, Platform Engineering, Cambridge, MA, October 2008-April 2021
    Engineering Manager, March 2018-April 2021
    Led the team that develops the alerting infrastructure responsible
    for monitoring Akamai's platform with operational
    efficiency. Managed up to 8 engineers, including matrix
    reporting. The team delivered alert correlation and notification
    services, and a web-based interface for viewing alerts.  Owned
    backend services spanning 3 teams and approximately 20 engineers,
    automating the response to thousands of alerts per day.

    Principal Lead Software Engineer, January 2015-February 2018
    Managed the Alert Management Systems team, including roadmap
    planning, performance evaluations, and career progressions.  Grew
    the team from 1 to 3 engineers.  Led the team to evolve a single
    database backend to geographically distributed, real-time replicas
    while maintaining four 9s of availability, migrate a variety of
    database clients to REST APIs, and establish modern development
    infrastructure and processes.  Delivered on schedule projects
    spanning engineers across three continents.

    Principal Software Engineer, July 2013-December 2014
    Carried out scalability projects in Query, a distributed,
    event-based system that continuously processes data
    from the entire Akamai platform.  Mentored over half a dozen engineers.

    Senior Software Engineer, February 2010-June 2013
    Designed and implemented multi-threaded system software
    for real-time publication, aggregation, delivery, and processing
    of data across Akamai's distributed platform.  Developed C, C++,
    Java, Python, and Perl interfaces used by both internal and
    customer-facing applications for monitoring, alerting, and
    reporting.  

    Senior Performance Engineer, October 2008-January 2010
    Used and developed tools to measure and analyze the performance, 
    robustness, and scalability of large distributed systems.  
    Took end-to-end responsibility of complex systems.

  IBM Research
    Advanced Enterprise Middleware, Watson Research Center, 
    Hawthorne, NY, Summer 2007
    Developed a replication middleware for distributed,
    multi-tier, server architectures.  Quantified the server
    replication and data partitioning performance benefits, as well as
    the consistency overhead, using the TPC-W transactional web
    commerce benchmark.  Patented the middleware's efficient,
    distributed, strong-consistency protocol.

  Intel Research
    Corporate Technology Group, Pittsburgh, PA, Summer 2006
    Built an event-driven, collaborative spam filter that
    employed a distributed protocol to defend against sybil attacks.

  Hewlett-Packard
    Enterprise Storage & Servers, Colorado Springs, CO, Summer 2005
    Developed and documented a logging mechanism used for
    asynchronous replication in a distributed disk array.

  FGAN e.V. (Fraunhofer FKIE)
    Bonn, Germany, Summer 2000
    Analyzed the H.323 protocol family, used for multimedia
    applications (VoIP) in packet switched networks, and summarized
    the results in a technical report, including detailed protocol
    description and performance evaluation of applications under IPv6
    in Solaris.

EDUCATION
  Ph.D. in Computer Science
    University of California, Riverside, August 2008
    Thesis: Synergy: Quality of Service Support for 
	    Distributed Stream Processing Systems
  M.Sc. in Computer Science
    University of California, Riverside, August 2005  
    Thesis: Adaptive Data Dissemination and 
	    Content-Driven Routing in Peer-to-Peer Systems
  Diploma in Electrical & Computer Engineering (5-year program) 
    University of Patras, Greece, March 2003
    Thesis: Implementation of Page Forwarding on Clusters