Boston, MA

Christopher Pacejo

Experienced network and storage systems programmer and distributed systems architect with a strong background in formal techniques.

I am a…

  • detail‐oriented engineer, attentive to the big picture
  • creative architect, attentive to the practical
  • believer in robust and accessible system design
  • student of both theory and practice

My employers ask me to…

  • lead groups in design and specification of new systems
  • empower peers by giving accessible and informative presentations on complex topics
  • evaluate, and propose and implement solutions to, system‐wide architectural issues
  • eliminate complexity from and improve reliability of problematic codebases
  • acquire and institutionalize deep knowledge of unfamiliar codebases
  • provide technical guidance for critical decisions

My peers seek my help with…

  • designing and evaluating concurrent algorithms
  • understanding idiomatic, correct, and performant use of modern C++
  • resolving semantic mismatches at the root of architectural issues
  • understanding unfamiliar systems and languages
  • eliminating performance bottlenecks in both CPU‐bound and I/O‐bound code paths
  • building robust and reliable core infrastructure

Ask me to share more about…

  • proving correctness of distributed algorithms running on eventually consistent storage
  • reworking an inefficient offline algorithm as an efficient online one, guided by formal methods tools
  • analyzing linear checksums for strength, orthogonality, and uniformity
  • developing competitive AIs to play my two favorite board games


NuoDB (Cambridge, MA)
Software Engineer, indexing team
developed formal verification framework for distributed object replication protocol in TLA+
applied automatic theorem solver (Z3) to discover bugs in code refactor
developed and formally verified online algorithm to reduce arbitrarily large histograms with logarithmic memory overhead
advised redesign of networking subsystem to minimize latency and stalls
took on responsibility for orphaned feature (distributed statistics collection), delivering several solutions to ease immediate customer pain points
ClearSky Data (Boston, MA)
Consulting Engineer (–)
Principal Software Engineer ()
designed and formally verified distributed algorithm to transfer ownership of portions of petabyte‐scale copy‐on‐write data structure
designed, implemented, and formally verified system for fail‐safe non‐disruptive cross‐datacenter migration of data path services
applied formal verification to discover bugs and verify fixes in data path interaction with eventually consistent storage
designed and implemented failover mechanism for highly‐available and robust NFS & SMB frontend appliance
designed and implemented system for non‐disruptive asynchronous upgrade of data path services
architected non‐disruptive migration path between highly‐available synchronously‐replicated relational database services
provided technical expertise in the use of PostgreSQL, HTTP, TCP, X.509/​TLS, Pacemaker, and POSIX/​Linux networking and block APIs
gave technical talks on PostgreSQL, REST, TLA+, and several internal topics
EMC/​XtremIO (Hopkinton, MA)
Senior Software Engineer
designed networking strategy for asynchronous data replication protocol
developed protocol for configuration synchronization within replicating pair
Corero Network Security (Hudson, MA)
Software Engineer
designed and implemented system to generate inter‐process communication layer and resource assignments for multicore processor from interface definitions (US Patent 9,442,782)
developed 40 Gbps network packet classifier and queueing system
designed and implemented 20 Gbps packet capture and indexing application
developed instruction scheduler for VLIW processor
Brown University (Providence, RI)
Research Assistant, Computer Science department
co‐taught graduate course on reduction semantics


Brown University (Providence, RI)
Ph. D. candidate, Computer Science
Worcester Polytechnic Institute (Worcester, MA)
M. S., Computer Science (2008)
B. S., Electrical & Computer Engineering (2006)