Hjörtur Líndal Stefánsson
Hafnarfjordur,RKV
Summary
Technology leader with a proven track record of driving operational excellence, optimizing engineering processes, and delivering measurable impact in fast-paced environments. Skilled in building high-performance teams, streamlining costs, and accelerating product delivery through innovative solutions and data-driven strategies. U.S. green card holder.
Overview
14
14
years of professional experience
Work History
Chief Technology Officer
Lucinity
08.2022 - Current
- Led a cloud cost optimization initiative, consolidating services and databases, implementing autoscaling, and reducing environment overhead, achieving over 35% reduction in cloud costs per customer, with projections to reach over 50%.
- Transitioned from bi-weekly releases to a CI/CD model, decreasing feature lead time by 85%, from 2 weeks to less than a day, enabling faster iteration cycles and improved time-to-market for high-impact features.
- Created formal on-call and incident management mechanisms, reducing reaction times by 95%, from days to under 30 minutes, while increasing system availability to 99.99%, resulting in better SLA adherence and enhanced customer trust.
- Established a Customer Engineering team focused on onboarding and support, reducing customer onboarding time by 75%, from an average of 12 months to 3 months, accelerating revenue recognition and improving customer satisfaction.
- Led cross-functional roadmap reviews and quarterly goal-setting with product, tech, and customer success, increasing milestone accuracy by 30% and reducing missed deadlines, resulting in stronger alignment on business priorities and improved delivery predictability.
- Led a team of over 30 engineers and engineering managers, driving alignment, accountability, and high performance across product and engineering teams.
Software Development Manager
Amazon
08.2020 - 08.2022
- Responsible for backend services that help enable video ad serving to Amazon's owned & operated publisher services, such as Prime Video, Twitch, Freevee and Fire TV.
- Led the scoping, design & development of the systems required to scale the video advertising stack for live events from supporting 3-4 million concurrent users to 22+ million.
- Drove infrastructure improvements to reduce hardware costs during peak season by 70% in 2021, while still supporting over 300% traffic growth in the same year.
- Created yearly technical roadmaps for the team, balancing technical debt, infrastructure and feature work amongst all the engineers on the team. Drove consensus on roadmaps with senior leadership, PMs and other stakeholders.
- Grew team from 2 to 11 engineers in 1.5 years with minimal employee attrition.
- Started transition from IC to management in August 2020, with the official role change taking place in June 2021.
Sr. Software Development Engineer III
Amazon
07.2018 - 08.2020
- Tech lead, responsible for technical direction of the team, as well as hiring and mentoring engineers.
- Owned the Entry service for Amazon's video ad-serving infrastructure, processing over 300 million daily ad-requests and millions of requests per second (during peak).
- Implemented features such as inventory share, podding, pre-fetching and header bidding for partners such as Prime Video, Freevee, Twitch and Fire TV, generating hundreds of millions in revenue for the company.
- Designed and implemented data pipelines for all video ad serving log data, processing terabytes of data every day.
Software Development Engineer II
Amazon
07.2016 - 07.2018
- Owned backend services in Prime used to query and modify customers' Prime subscription information, supporting hundreds of millions of Prime customers worldwide.
- Reduced service latency by over 50% by diving deep on service behavior and downstream dependencies, delivering a fix in less than a week with no regressions or issues reported.
- Designed and implemented a multi-tenant architecture for the team's membership aggregation service, which enabled different IPs under the Prime banner (Fresh, Prime Business etc.) to implement and modify their aggregation/transformation logic without involving engineers on the team.
- Technical lead with a focus on mentoring junior engineers, guiding towards best practices and shaping the team culture.
Senior Online Programmer
Ubisoft
01.2015 - 07.2016
- Lead migration of all of team's services from WCF to .NET WebApi, to reduce tech debt and increase developer productivity.
- Created core-component libraries for all WebApi services owned by the team, reducing boiler-plate code in each service by approx. 50%.
- Designed and implemented a wallet & micro-transaction service for Rainbow Six Siege (competitive multiplayer 1st person shooter), supporting tens of millions of players worldwide.
- Owned the auth service used in all of Ubisoft's games.
Senior Software Engineer
CCP
05.2010 - 09.2014
- Designed, implemented, and operated a single-sign-on service (OAuth 2.0), controlling access and permissions to all of company's games and websites.
- Owned other backend services related to customer data and virtual goods used for DUST 514 (online 1st-person shooter game) and EVE Online (massively multiplayer online role-playing game).
Education
MSc - Information Technology
IT University of Copenhagen
Copenhagen, Denmark05-2006
BSc - Computer Science
Reykjavik University
Reykjavik, Iceland06-2003
Skills
- Leadership
- Mentoring
- Hiring
- Engineering Management
- Distributed Systems
- Scalability
- Cloud Architecture
- Software Architecture
Timeline
Chief Technology Officer
Lucinity
08.2022 - Current
Software Development Manager
Amazon
08.2020 - 08.2022
Sr. Software Development Engineer III
Amazon
07.2018 - 08.2020
Software Development Engineer II
Amazon
07.2016 - 07.2018
Senior Online Programmer
Ubisoft
01.2015 - 07.2016
Senior Software Engineer
CCP
05.2010 - 09.2014
MSc - Information Technology
IT University of Copenhagen
BSc - Computer Science
Reykjavik University
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