Adam M. Phelps

Principal Engineer · Distributed Systems · Data Infrastructure

San Francisco, CA amp@ampworksstudio.com LinkedIn GitHub

Summary

Twenty-five years building and operating large-scale distributed systems, with deep specialization in data infrastructure, storage, and DNS-layer security. Sixteen years at OpenDNS / Cisco Umbrella, currently Principal Engineer on DNS security for a service operating at roughly a trillion queries per day — about half from enterprise customers globally (including FedRAMP-authorized environments for US federal agencies), half from public users trusting the OpenDNS Anycast addresses. A prior decade at 3PAR as the initial engineer on its Remote Copy replication system (intern to Staff Engineer through the 2007 IPO), with multiple US patents. In parallel, principal of AmpWorks Studio LLC and an active maker working out of a personal metal and fabrication shop. Open to a new role at 3/5 time or less (replacing, not alongside, the current 4-day-week Principal Engineer role); the remaining time goes to art and fabrication.

Experience

Cisco Systems — Cisco Umbrella

2015 – Present

Principal Engineer, DNS Security

Joined via the 2015 OpenDNS acquisition. Technical Leader, Data Infrastructure (2015–2021); Principal Engineer, DNS Security (2021–present). 4 days/week since 2018.

  • Principal engineer on the Umbrella DNS service — roughly a trillion DNS queries/day with strong reliability, split ~half enterprise (incl. FedRAMP-authorized US federal environments) and ~half public users on the OpenDNS Anycast addresses.
  • Led Cisco's side of the Umbrella Unified Policy initiative — designed and delivered evaluatable customer policy across Umbrella's product surface, coordinating multiple internal teams. It evolved into SSE and then Cisco Secure Access (Cisco's current SASE/SSE offering).
  • Mentored engineers across the data-platform org over many years.

OpenDNS

2010 – 2015

Senior Engineer / "Data Magician"

  • Helped build OpenDNS's initial data analytics systems in the early days of Hadoop, establishing the analytics pipeline and data architecture from scratch.
  • Built real-time pipelines on Kafka and Storm alongside the batch analytics layer.
  • Led the team that built IntelDB, the internet-scale graph knowledge store (domain relationships, hosting infrastructure, DNS topology) that became the data substrate behind the Investigate threat-intelligence product.
  • Wrote much of OpenDNS's early VPN and proxy software; collaborated with security researchers to turn the data infrastructure into a substrate for threat intelligence.

3PAR Inc. (formerly 3PARdata; now part of HPE)

2000 – 2010

Staff Engineer, Storage Systems

Software Engineering Intern (2000–2001, during Stanford MS) → Staff Engineer (2001–2010).

  • Initial engineer on 3PAR's Remote Copy replication system, owning it from the internship through full-time tenure as it scaled with the company through the 2007 IPO.
  • Authored multiple US patents from the Remote Copy work — link-failure recovery via snapshot-diff resync, snapshot tree differencing, and host-based write ordering for parallel-preserving replication.

Carnegie Mellon University — Parallel Data Lab (PDL)

1997 – 1999

Undergraduate Researcher

  • Solo work on a video streaming system over NASD (Network-Attached Secure Disks) under PI Greg Ganger; picked up from Howard Gobioff (later on Google GFS).

AmpWorks Studio LLC

2016 – Present

Founder / Principal

  • California LLC for hardware design, embedded systems, and bespoke engineering — at the intersection of microcontrollers, networked devices, and large-scale interactive installations.

Patents

US 7,155,635 B1 Handling Link Failures in Remote Mirroring Applications Using Snapshots · granted 2006-12

Recovery from network/link failures in remote mirroring via snapshot-diff resync.

Sole inventor

US 7,100,089 B1 Determining Differences Between Snapshots

Snapshot tree differencing for storage replication.

Sole inventor

US 2012/0079222 (application publication) Host Write Based Write Ordering

Storage replication ordering that preserves parallel write semantics on the secondary. (Application-publication number — verify granted number before relying on it.)

Sole inventor

US (co-invented)Variable Amplitude Data Output Signal

Co-invented signaling patent from the 3PAR era.

Inventors: Adam M. Phelps, Richard T. Dalzell, Hariprasad Mankude Bhasker Rao

Education

Stanford University

1999 – 2001

M.S., Computer Science (Systems track)

Carnegie Mellon University

1995 – 1999

B.S., Computer Science, School of Computer Science

Selected Skills

System Design & Architecture: distributed data pipelines · real-time streaming (Kafka, Storm) · batch analytics (Hadoop) · internet-scale graph databases · enterprise storage / replication / snapshots · DNS-layer security · networked embedded devices

Engineering Leadership: cross-team technical leadership · architecture & trade-off framing · design/code review at scale · technical writing (design docs, RFCs)

Languages: C · Python · Go · Rust · Perl · Java

Hardware: custom PCB design · embedded firmware · FastLED addressable lighting · MPR121 capacitive sensing · RS485 networking · metal & fabrication

AI Tools & Workflows: Claude · GitHub Copilot · OpenAI Codex · AI-assisted production engineering with human review