Kunpei Sakai
Chief Technology Officer at ドワンゴ
Chiyoda, Japan
Summary
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RockstarKunpei Sakai is a seasoned technology leader and CTO based in Chiyoda, Japan, with 15 years of engineering experience and 13+ years in professional software roles spanning startups to Google. He blends hands-on backend and cloud expertise—contributing to high-profile open-source projects like the Go toolchain, Kubernetes kompose, Sinatra/Padrino and Google Cloud sample solutions—with strategic leadership in large-scale service architecture and AWS/GCP operations. At Dwango he has progressed through architecture, infrastructure and development leadership roles to Chief Technology Officer, consistently focusing on reliability, CI/CD migration and developer productivity. His background includes driving platform consolidation and efficiency improvements in game and media businesses at DeNA and KADOKAWA, where he rethought microservice trade-offs to cut operational cost. A pragmatic engineer who still commits code, he has fixed core parsing, HTTP and cloud upload flows across major repos while also implementing Terraform modules and robust CI. He combines systems-level thinking with an appetite for code-level fixes, making him equally effective in boardrooms and pull requests.
15 years of coding experience
9 years of employment as a software developer
Japanese, English
Github Skills (71)
google-cloud-platform10
programming-language10
grapesjs10
testing10
databases10
http10
azure-functions10
firebase-cloud-functions10
terraform10
gcp10
ruby10
automation10
google-cloud10
rest-api10
appengine10
Programming languages (11)
Github contributions (5)
terraform-google-modules/terraform-google-sql-db
Nov 2018 - May 2020
Creates a Cloud SQL database instance
Role in this project:
DevOps Engineer & Test Automation Engineer
DevOps Engineer & Test Automation EngineerContributions:45 commits, 19 PRs, 12 pushes in 1 year 6 months
Contributions summary:Kunpei primarily focused on enhancing the testing infrastructure and improving the quality of the Terraform modules for Google Cloud SQL databases. Their contributions include adding and modifying integration tests, especially for High Availability (HA) configurations and the implementation of SQL Server support. They also addressed bugs and ensured the tests covered multiple users and configurations, reflecting a strong focus on reliability and comprehensive validation.
database-instancegcpgooglecloud-sqlsql
golang/net
Sep 2017 - Oct 2020
[mirror] Go supplementary network libraries
Role in this project:Full-stack Developer
Full-stack DeveloperContributions:42 commits, 2 comments in 3 years 2 months
Contributions summary:Kunpei primarily contributed to the `golang/net` repository, focusing on the HTML parsing and related functionalities. Their work included updating section numbers and quotes within the HTML parsing logic, adding support for template insertion modes, and addressing end-of-file cases. The user also fixed minor typos and removed duplicate words. Furthermore, the user updated various features for parsing code.
golangospfnetworkingbgpsdn
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