Satoshi Tagomori
Principal, SAKURA Cloud at Freelance
Chiyoda, Japan
Summary
🤩
Rockstar🎓
Top SchoolSatoshi Tagomori is a Principal at SAKURA Cloud and a 15-year software engineer specializing in distributed systems and data processing. He is a core maintainer and major developer of Fluentd (a CNCF project) and MessagePack’s Ruby implementation, and the original author of Norikra and Woothee, demonstrating deep expertise in high-throughput logging and stream processing. His career spans product-grade backend work at Treasure Data and LINE, where he led large migrations, redesigned ingestion pipelines, and drove Fluentd v0.14/v1.0 plugin API changes used widely in production. A frequent conference speaker (CloudNativeCon, LinuxCon, RubyConf) and organizer/founder of the ISUCON performance contest, he blends hands-on systems programming with community leadership. His open-source contributions reach into language runtime internals (Ruby VM and extension APIs) and high-performance HTTP server integrations, reflecting an unusual mix of low-level VM work and large-scale distributed engineering. Based in Chiyoda, Tokyo, he also consults and maintains a solo-built lifelog iOS service, showing product-minded full-stack capabilities.
15 years of coding experience
12 years of employment as a software developer
University of Tokyo
Japanese, English
Stackoverflow
126reputation
18kreached
8answers
0questions
Github Skills (32)
json10
programming-language10
testing10
http10
c1110
ruby10
c1710
httpd-server10
http-server10
logging10
messagepack10
mruby10
test-automation10
utf9
debug9
Programming languages (17)
Github contributions (5)
fluent/fluentd
Nov 2011 - Mar 2022
Fluentd: Unified Logging Layer (project under CNCF)
Role in this project:
Back-end Developer
Back-end DeveloperContributions:3 reviews, 1235 commits, 471 PRs in 10 years 4 months
Contributions summary:Satoshi primarily contributed to the Fluentd project by fixing bugs and implementing enhancements in various areas. They addressed issues related to process handling, improved logging, and added features such as the ability to parse and handle JSON structures in log messages. The user demonstrated proficiency in Ruby and made targeted code changes across multiple plugin files.
fluentdrubyloggingunified-loggingcncf
msgpack/msgpack-ruby
Jul 2014 - May 2022
MessagePack implementation for Ruby / msgpack.org[Ruby]
Role in this project:Back-end Developer & Test Automation Engineer
Back-end Developer & Test Automation EngineerContributions:60 reviews, 340 commits, 173 PRs in 7 years 11 months
Contributions summary:Satoshi primarily focused on improving the test suite for the `msgpack-ruby` library. They refactored and separated specifications related to the `MessagePack::Buffer` class, making them platform-specific. Additionally, they addressed code style issues and explicitly encoded strings as UTF-8. The contributions included fixes for the test suite and refactoring.
msgpackrubymessagepack
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