Philip J. Hollenback

philiph@pobox.com
San Francisco
www.linkedin.com/in/philiph

Overview

I’m a Staff Software Engineer with deep roots in Site Reliability Engineering and security operations. Over the last decade I’ve moved from release engineering through SRE to infrastructure-focused software development. Day to day I work on identity, authentication, and the services behind them, mostly in Python.

Experience

LinkedIn, Sunnyvale, CA

Staff Software Engineer - August 2023 to May 2026

Technical lead on a 6-person infosec infrastructure team building software services around identity and authentication standards (LDAP, SSO).

• Led migration of a clustered Java LDAP service from Windows to Linux: wrote a new installer and integrated it with LinkedIn’s deployment and monitoring stacks.
• Rewrote LinkedIn’s internal Python LDAP client library. The new version discovers servers via DNS TXT records and uses Python multiprocessing for connection management, allowing long-running clients to be moved between LDAP servers without restart.
• Drove an SSO integration program across the company: helped 500+ services migrate to SSO in six months, coordinating across 10+ partner engineering teams.

Staff Site Reliability Engineer - September 2019 to August 2023

Technical lead on an infrastructure tooling team. Designed and built an automated framework for certifying new Linux OS releases against the LinkedIn software stack.

• Fleet under test: 100,000+ hosts. Framework integrated 50+ test suites contributed by other engineering teams.
• Replaced a manual two-week certification cycle with an automated process completing in under one day. Implemented in Python.
• Certified 10 OS releases through the framework before rotating off the team.

Oracle, San Francisco, CA

Senior Security Operations Engineer - November 2016 to August 2019

Technical lead in Security Operations for Oracle Cloud, focused on vulnerability management, identity hardening, and patch automation.

• Built and operated a vulnerability scanning system covering several thousand core Oracle Cloud hosts.
• Led Yubikey-based 2FA rollout to ~300 employees, eliminating non-2FA logins from the authentication infrastructure.
• Wrote a Fabric-based monthly patching system for the team’s authentication-infra fleet (several hundred servers).
• Built Grafana dashboards for security operations metrics and ran biweekly operational excellence reviews.

Lookout, San Francisco, CA

Senior Production Engineer - July 2015 to November 2016

Release engineering team member at a mobile security company. Managed Jenkins, Gerrit, and Artifactory. Automated service deployments using NixOS on AWS.

Highlight: Built end-to-end automated deployment for Artifactory. The one-step deploy fully provisioned and configured all associated AWS components.

Goodreads, San Francisco, CA

Senior Systems Engineer - April 2014 to July 2015

Half of a two-person operations team at Goodreads (one of the top one hundred websites by traffic). Built automation and monitoring in shell, Ruby, and Perl.

Highlight: Automated MySQL database failover in Ruby. Replaced a manual 45-minute process with a 5-minute automated one.

Earlier positions on LinkedIn.

Skills

Python, Go, Linux internals and operations, distributed systems, site reliability engineering, identity and access management (LDAP, SSO, OAuth), security operations, infrastructure automation, observability (Grafana), AWS, release engineering. Currently expanding Kubernetes depth.

Education

Bachelor of Science in Computer Science, The University of Montana. Emphasis in Artificial Intelligence. Minor in English Literature.