About jojo

A software engineer who crosses boundaries from the server side.
Works at 10X, and builds Pululu on the side with a friend from the same new-grad intake.

jojo’s houseSee it on the map

Adventurer cardTokyo

Name: jojo
Class: Software Engineer @ 10X
Base: Tokyo
Skills: GolangReact (TypeScript)Dart / FlutterSwiftUIGCPAWS
Engineer since: 2019.04〜

A software engineer focused on the server side, building products with a "do whatever it takes" attitude — crossing boundaries to create real product value.
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What I go by

Cross the borders
For the product's value, job titles don't set the limits.
Start from the real problem
Before building, make sure what we're solving.
Stuck? Go for a walk
Clear my head, then come back.

Recently watched

Things I like

Sauna
Someday I'll build my ideal sauna. For now, I want to visit a smoke sauna in Estonia.
Houseplants
Growing four Platycerium (staghorn ferns).
Walking
When I get stuck, I walk and clear my head to refresh.

Career

2023.02 – Present

10X, Inc.Software Engineer

Building an online supermarket platform with several enterprise partners in a small, distributed team. Lead development of the e-commerce product for end users. On the ranking feature, designed and implemented the client and backend — API design, data modeling, client integration — meeting strict latency and reliability requirements. Redesigned the architecture and Firestore schema to significantly cut latency, shipping safely behind feature flags. Drove projects through to release and established code-review and testing practices.
2020.02 – 2023.01
Visional Incubation (BizHint)Full-stack Engineer → Product Manager

A cloud-service matching platform for SMB owners with 300k+ members. Built it with Go and React (TypeScript), from requirements to implementation.
Details
- 2022.06Led, as PdM, a B2B platform that lets customers manage their own ads
- 2021.09Renewed the iOS app with one designer; MAU up 10%
- 2021.04Built a survey feature as a revenue source beyond lead generation
- 2020.09Systematised the email marketing behind 90% of revenue; company award
- 2020.02Moved here when Bizreach became a holding company
2019.04 – 2020.01

Bizreach, Inc.New-grad Engineer

Asked for “the most chaotic team in the company” and was the only one in my cohort sent to the new BizHint business.