# Don Hayler

> Staff Software Engineer at SunRun

Location: San Francisco, California, United States
Profile: https://flows.cv/donhayler

Software Engineer with 15+ years of experience.  I enjoy designing and writing machine learning systems and highly performant scalable software and delivering software that solves real world customer problems. I like building consensus around requirements and implementations as well as debugging difficult issues.

Recommender Systems, Big Data, Machine Learning, Middleware, Full-stack Development, SQL Tuning, REST, Java, Agile

## Work Experience
### Staff Software Engineer @ Sunrun
Jan 2023 – Present | San Francisco Bay Area
I work on the Design Engineering team working to build tools used to design rooftop solar installations so people can power their homes with clean energy.

### Consulting Member Technical Staff (Cloud Commerce) @ Oracle
Jan 2016 – Jan 2022
• Designed and implemented Personalization / Audience Segmentation framework and features providing over a million real time personalized shopping experiences per day worldwide.
• Developed requirements, architecture, and UX for A/B Testing functionality and led a team to implement the feature for Commerce.
• Built consensus across teams and with executives.  Customer-oriented requirements development. Helped improve development process issues across the entire organization. Mentored engineers. Debugged low-level issues in complex legacy code hierarchies. Performance Testing & SQL tuning.

### Principal Member of Technical Staff (Social Network) @ Oracle
Jan 2012 – Jan 2016
• Developed a system to provide real-time personalized contextual recommendations for users and documents in Oracle’s Enterprise Social Network / Messaging application (similar to Slack) based on big data enterprise activity (connections, document edits, etc…) for 20,000 users, including human-understandable recommendation reasons.

### Principal Member Technical Staff (Activity Graph) @ Oracle
Jan 2008 – Jan 2012
• Developed a collaborative filtering system to rank and recommended enterprise objects (users, documents, sales deals, etc…) based on enterprise activity (connections, document edits, tags, etc…).
• Implemented autocomplete and instant search systems with security filtering and ranking.
• Granted patent US9613165B2 (secure ranked autocomplete)

### Staff Software Engineer (SSO Reverse Proxy) @ BEA Systems
Jan 2005 – Jan 2008
• Led a team to take over and complete a failing reverse proxy SSO product to integrate web content with corporate portals via non-invasive content insertion.
• Evangelized agile development within division and transitioned multiple dev and PM teams to Scrum while releasing higher quality products. Improved development process issues across the entire org.
• Granted patents US7865943B2 (credential vault encryption), US8136150B2 & US8397283B2 (role mapping), US9548985B2 (non-invasive content insertion proxy), US7886352B2 (interstitial pages), US8745485B2 (remote tags), US7904953B2, US7861289B2, & US7861290B2 (pagelets).

### Senior Software Engineer (Corporate Portal) @ Plumtree Software
Jan 2002 – Jan 2005

### Software Engineer (Cloud Schematic Renderer) @ Incremental Images
Jan 2000 – Jan 2001

### Software Engineer (Chat Bots) @ Extempo Systems Inc
Jan 1999 – Jan 2000


## Education
### AB in Computer Science
Harvard University


## Contact & Social
- LinkedIn: https://linkedin.com/in/hayler

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Source: https://flows.cv/donhayler
JSON Resume: https://flows.cv/donhayler/resume.json
Last updated: 2026-04-12