Samuel Cox
Senior Staff Software Engineer at PayPal
Pflugerville, Texas, United States
Summary
🤩
Rockstar🎓
Top SchoolSamuel Cox is a Senior Staff Software Engineer with 11+ years of experience building and stewarding large-scale Java and non-blocking systems, currently driving core framework development at PayPal that supports thousands of applications. He focuses on developer productivity, automation, cost-benefit tradeoffs, and team efficiency—leading test and build optimizations that slashed build times by 75% and reduced compute usage. An active open-source contributor, he has improved high-profile projects like Akka-based squbs and RESTEasy/reactor-netty integrations to harden reactive REST clients and server adapters. Known for ownership and practical engineering discipline, he pairs deep hands-on coding with mentorship, retrospectives, and pragmatic automation (including dotfile-driven developer tweaks). Based in Pflugerville, TX, he brings a rare blend of infrastructure-level impact and a curiosity for new languages and tooling, with a background spanning Java, Scala, Clojure experimentation, and tooling for scalable non-blocking performance.
11 years of coding experience
17 years of employment as a software developer
BS, Computer Science, BS, Computer Science at The University of Texas at AustinBBA, Finance, BBA, Finance at Stephen F. Austin State University
Github Skills (13)
scala10
javas10
rest-api10
akka10
reactive-programming10
reactor10
akka-streams10
java10
akka-http10
netty9
reactive9
http9
testing8
Programming languages (9)
Github contributions (5)
paypal/squbs
May 2018 - Aug 2019
Akka Streams & Akka HTTP for Large-Scale Production Deployments
Role in this project:
Back-end Developer
Back-end DeveloperContributions:7 reviews, 10 commits, 35 PRs in 1 year 3 months
Contributions summary:Samuel primarily focused on enhancing the `squbs` project by adding new functionalities and improving existing ones. Their contributions involved implementing features related to request attributes, including adding and removing attributes. Furthermore, the user addressed logging errors during service startup and corrected coding conventions within the project, specifically regarding the `Unicomplex` module. They also improved the perpetual stream's materialization value, and addressed timing issues while depending on actor state.
http-clientstreamsscaleakka-streamsakka-http
resteasy/resteasy
Jun 2019 - Dec 2022
An Implementation of the Jakarta RESTful Web Services Specification
Role in this project:Back-end Developer
Back-end DeveloperContributions:55 reviews, 16 commits, 17 PRs in 3 years 6 months
Contributions summary:Samuel primarily contributed to the `resteasy` project by implementing and fixing features related to reactive programming, specifically integrating `reactor` libraries. They developed and refined the `FluxRxInvokerImpl` and `MonoRxInvokerImpl` classes, enabling reactive streams for REST client calls. The user addressed bugs and improved the stability of the reactor-netty server adapter, including fixing a `null` case that caused hang and addressing various exceptions in the server-side implementation. They also made other enhancements to `ReactorNettyHttpResponse`, including adding features like content-type, content-length, and header support.
restfulspecificationweb-servicesweb-services-restfuljakarta
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