# Tiernan Garsys > Staff SWE | Tech Lead @ Riot | Ex-(Google/Twitch) | Python, Go, Typescript, Javascript | Experienced in cross-disciplinary collaboration, teaching, and mentoring Location: Seattle, Washington, United States Profile: https://flows.cv/tiernan I'm a self-directed senior developer with tech lead and mentorship experience across Google, Twitch, and Riot who excels in collaborating across disciplines and teams. I have extensive experience in full stack development of high-traffic critical backend services, internal tools, and console applications using Python, Go, Java, Typescript, and Javascript alongside industry-standard tools like AWS, Docker, Angular, React, Postgres, and Node. I have a strong track record of collaborating across disciplines with SRE, release engineers, UX designers, and technical users, as well as guiding and uplifting others as a tech lead and intern host. I always strive to solve the problems of today in ways that anticipate the problems of tomorrow. For fun, I enjoy music production, thinking about game design, Sixers basketball, and history podcasts! I also play bass guitar, if anyone's band has an opening :) ## Work Experience ### Staff Software Engineer @ Riot Games Jan 2022 – Present Tech Lead, Global Player Support Engineering ### Senior Software Engineer @ Oscar Health Jan 2019 – Jan 2021 | New York Tech Lead on the Plans & Benefits (P&B) Adjudication team as part of NextGen initiative. Scoped and prioritized work using Agile methods. Consulted on client team integrations with P&B services. Led cross-functional effort to build a business rule engine in Python and Go on AWS. Worked with ops to achieve full compatibility with legacy ruleset, avoiding costly rewrite of core business logic. Designed new schema and evaluator for engine, reducing average evaluation time by > 90%. Hour-long updates requiring engineering help became self-serviceable by ops users in minutes. Modeled technical excellence within Oscar. Led adoption of standardized Postgres-to-BigQuery stream replication and monitoring by P&B. Represented P&B work at engineering learning events. ### Software Engineer L4 @ Google Jan 2016 – Jan 2019 | San Francisco Bay Area Served as full stack engineer on Rapid, the release automation platform for products such as Search and YouTube. Collaborated on UX design, devops, and roadmap in a self-directed team of 5. Owned features built with Java, Python, Typescript, JS, and Angular. Architected distributed system features using gRPC, Spanner, pubsub, blob storage, and the Google build-test-deploy stack. Designed an error debugging system that saved hundreds of eng-hours during production releases. Served in a monthly on-call rotation providing incident response and user support. Contributed to 5+ post-mortems and responded to 350+ posts on the Rapid user mailing list. Collaborated with release engineering, site reliability, and SWE users across Google to debug and improve release processes. Hosted 4 interns for the STEP program, which supports 1st and 2nd year students from backgrounds underrepresented in tech. ### Software Engineer @ Twitch Jan 2015 – Jan 2016 | San Francisco Bay Area Performed frontend development in JS for Xbox, maintaining feature parity with peer clients. Wrote Mixpanel plugin for Twitch C++ SDK to standardize telemetry between mobile and console apps. ### CIS 120 Head Teaching Assistant @ University of Pennsylvania Jan 2013 – Jan 2015 | Greater Philadelphia Area Taught weekly recitations, receiving a 4.5/5.0 or greater instructor rating each semester. Coordinated grading, office hours, and content scheduling for ~20 TAs in 150-200 student courses. ### CIS 120 Teaching Assistant @ University of Pennsylvania Jan 2012 – Jan 2013 Performed grading and content planning for a weekly 15 - 20 student lab section. Held weekly office hours to assist students with homework and material review. ### Software Engineering Intern @ Google Jan 2014 – Jan 2014 Ads & Commerce - Google Wallet ### Software Engineering Intern @ Google Jan 2013 – Jan 2013 Ads & Commerce - Google Content AdWords Front End ## Education ### Bachelor’s Degree in Computer Science University of Pennsylvania Jan 2011 – Jan 2015 ## Contact & Social - LinkedIn: https://linkedin.com/in/tiernangarsys - Website: https://tiernan.site --- Source: https://flows.cv/tiernan JSON Resume: https://flows.cv/tiernan/resume.json Last updated: 2026-03-22