Kei Kubo
CEO at 600, Inc.
Tokyo, Japan
Summary
👤
Senior🎓
Top SchoolKei Kubo is a serial founder and CEO with 14 years building cloud-native web platforms, payment integrations, and social web tools from Tokyo. He has led companies from bootstrapped authoring tools (CSSEZ) and local social networks to cloud hosting (fluxflex) and payments (WebPay), and later shaped strategy for LINE Pay. Technically hands-on across Python, Ruby, PHP, JavaScript and AWS, he contributed to the widely used Active Merchant library by adding a WebPay gateway with JPY support and test coverage. His work blends product instincts with infrastructure expertise—shipping scalable, testable systems and monetizable developer services. A Carleton College alumnus in Computer Science and Political Science, he brings entrepreneurial creativity paired with practical engineering discipline.
14 years of coding experience
10 years of employment as a software developer
B.A., Computer Science, Political Science, B.A., Computer Science, Political Science at Carleton College
Stackoverflow
3reputation
208reached
0answers
1question
Github Skills (16)
ruby10
unit-testing10
apim10
activemerchant10
test-integration10
payment-gateway10
api10
test-unit10
unit-test10
integration-testing10
testing10
test-driven-design9
java6
jsp6
spring-boot6
Programming languages (1)
Github contributions (5)
activemerchant/active_merchant
Sep 2012 - Dec 2013
Active Merchant is a simple payment abstraction library extracted from Shopify. The aim of the project is to feel natural to Ruby users and to abstract as many parts as possible away from the user to offer a consistent interface across all supported gateways.
Role in this project:
Back-end Developer & Test Automation Engineer
Back-end Developer & Test Automation EngineerContributions:7 commits in 1 year 2 months
Contributions summary:Kei primarily contributed to the implementation of a new payment gateway, WebPay, within the Active Merchant library. This involved adding the gateway's core functionality, including purchase, void, and refund capabilities. Furthermore, the user wrote unit and integration tests to ensure the correct functionality and currency handling for the new gateway, including support for Japanese Yen.
ecommerceaimadyenpayment-processingpayment
keikubo/Python-FastCGI-Sample
Jul 2011 - Dec 2011
Contributions:11 commits in 5 months
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