SOFTWARE STUDIO · JAPAN · UTC+9
We build software
and keep it running.
BUILD GEEKS is a software studio in Japan, run by an engineer with 19 years in production. We design, build and operate our own products across web, iOS and LLM systems. Client work gets the same treatment.
See the products01 / PRODUCTS
Things we built and run.
Our own products, designed and operated in-house. The first three come with their numbers and key features.
BJJ Techniques
BJJ Learning App
TRACTION
- 42
- Countries with active users
- 67%
- Of users are outside Japan
- 97.7%
- Of new users complete onboarding
- 44 → 368
- Monthly active users, Apr → Aug 2026
In-app analytics, 90 days to September 2026.
Details →
BJJ FLOW
HIIT & Mobility for Grapplers
WHAT IT DOES
- 27 moves, including shrimp, reverse shrimp, bridge, sit-through and Granby roll, each with a looping demo video
- Steps, tips and how each move helps your jiu-jitsu
- 14 ready-made programs: 9 HIIT and 5 stretch
KaizenLab
Hypothesis Canvas Management Tool
WHAT IT DOES
- Hypothesis canvas creation and management
- Persona design and interview recording
- Verification tracking and learning accumulation
Also in the catalogue
The people who design it are the people who run it.
02 / OPEN SOURCE
Code you can read.
Tools we needed for our own agent-driven development, then published.
03 / WRITING
Notes from the work.
English on dev.to, Japanese on Zenn.
04 / WORKING WITH US
If you want us on your project.
WHAT WE TAKE ON
AI agent adoption and PoC builds. Technical advisory and architecture review. SRE, cloud and IaC diagnosis, with hands-on fixes.
HOURS
Japan-based (JST / UTC+9). Reserved overlap hours: 8–11am JST for US Pacific afternoons, 4–7pm JST for European mornings.
HOW IT STARTS
Send a short note about the problem. We reply within a few business days.