# Yasuhiro Matsuda

> Software Architect

Location: Palo Alto, California, United States
Profile: https://flows.cv/yasuhiro

Specialties: Search Engine, Social Graph Engine, Graph Database, Lucene, Database, query processing (language design, compiler, optimizer, execution engine), SQL, Java, Scala, distributed systems, algorithms, software architecture, design and implementation

## Work Experience
### Engineer @ Oscilar Inc
Jan 2021 – Present
Risk workflow/rule language and execution engine

### Distinguished Engineer @ WePay
Jan 2020 – Jan 2021 | Redwood City
- Architected a distributed graph database with a SQL like query language. We designed from the storage layer to the query engine from scratch.
- Architected a new payment processing engine, which is a highly reliable, highly scalable fault tolerant system. It is a workflow like system built on top of Waltz distributed log. It stores execution states in Waltz for durability and failover. The entire system is designed for consistency guarantee in the active-active multi-region deployment in mind.

### Principal Engineer @ WePay
Jan 2016 – Jan 2020 | Redwood City, CA
Architected Waltz, a distributed write-ahead log, which is built for multi-region transaction consistency.
blog: https://wecode.wepay.com/posts/waltz-a-distributed-write-ahead-log
code: https://github.com/wepay/waltz

### Software Engineer @ Confluent
Jan 2015 – Jan 2016 | Palo Alto, CA
Designed and implemented Kafka Streams. Kafka Streams is a stream data processing library. It is a part of Apache Kafka. 
Focused on the design and implementation of the following areas.
- KStream/KTable DSL design
- Time-based Flow control
- Topology analysis
- Task distribution/balancing
  - integration with Kafka's consumer group protocol
  - fast fault recovery using standby tasks

### Software Engineer @ FortyTwo Inc.
Jan 2012 – Jan 2015 | San Francisco Bay Area
Architected Kifi search engine, which uniquely combine personalization and social aspect. A user creates keeps (which are like bookmarks) of web pages. The search engine provides full-text search of keeps. Page titles can be personalized, and pages can be tagged. Personalized title and tags are also searchable by the user, but not by other users. A keep can be public or private. If public, the user's social connections can discover the page in search results, and this way the user can help friends finding useful/interesting information. If a keep are private, the fact that the user kept the page is hidden from other users, so the users privacy is protected.
The engine deals with content search, personalized metadata search (personalized titles, tags, and more!) and social graph processing at query time in distributed manner.

### Software Architect @ LinkedIn
Jan 2008 – Jan 2012
Distributed online social graph processing - Architected the distributed graph database (GraphDB) for LinkedIn social graph (algorithm, data structures, new query language, query processing architecture, internal schema representation, query compilation and execution engine implementation, new robust log-structured storage engine, low overhead cluster communication).

Search backend - Implemented realtime indexing/search, faceted search, nested document search and distributed search on top of Lucene.
Social search and Relevance

A generic list-oriented data storage/index (named Rydeen) for fast event ingestion and realtime aggregation (powering LinkedIn Today)

LinkedIn People Search, Job Search, LinkedIn Signal (twitter/linkedin update search, realtime article trending), LinkedIn Today (personalized news), and Distributed Social Graph Database (used by many applications at LinkedIn), etc.

### Principal Engineer @ LogLogic
Jan 2007 – Jan 2008
Responsible for design/implementation of the search backend on LogLogic appliances. Wrote a whole new custom query layer on top of Lucene's low level APIs. It handles a huge amount of time stamped log data. 
Did numerous improvements in memory usage and search performance.
Redesigned distributed search algorithm and communication protocol.

### Principal Member of Technical Staff @ Oracle
Jan 1994 – Jan 2007
Responsible for design and implementation of Text/XML search engine in Oracle RDBMS kernel. Designed internal framework of text indexing pipeline and query execution in Oracle. Wrote the query execution layer.
Full-text search/SQL integration
Enterprise search/crawler/multi-data-source integration
Intranet crawler in Java
Participated in W3C XQuery Full-Text Task Force

### Technical Staff @ Oracle Japan
Jan 1993 – Jan 1994
Software development
Oracle Gateways (distributed transaction with third party RDBMSs, SQL query transformation/optimization)

### Software Development Engineer @ Digital Equipment Corporation  Japan
Jan 1988 – Jan 1993
R&D engineer at Japan R&D center
Software development (DEC Rdb/VMS)
SQL standard representative (ISO, JIS , MIA)
I18n/L10n


## Education
### BS
Tokyo Institute of Technology


## Contact & Social
- LinkedIn: https://linkedin.com/in/ymatsuda
- Portfolio: http://sna-projects.com/sna/
- Portfolio: http://www.42go.com/team.html#yasuhiro
- Portfolio: http://www.42go.com

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Source: https://flows.cv/yasuhiro
JSON Resume: https://flows.cv/yasuhiro/resume.json
Last updated: 2026-04-10