A small studio building durable tools for thinking.
Shanghai Seii.top Technology Co., Ltd. is an independent product studio based in Shanghai. We build CaptureX — the capture layer we wished existed for our own deep-work stacks.
Why we exist
A decade ago, an app called Catch Notes (originally 3banana Notes, 2010–2013) showed what was possible when a notes app treated capture as a first-class operation — fast, multimodal, opinionated. It shut down. We've been waiting for its successor ever since.
Today, two things changed. First, multimodal LLMs make it realistic to organize captures automatically without forcing the user to tag everything by hand. Second, git plus a few hundred lines of markdown make a sovereign, diffable, portable knowledge store any knowledge worker can run today.
CaptureX is our answer: capture anything from your phone and desktop, govern it with a 4-section schema, mirror it as plain markdown into a git repository you own. That's the whole pitch in v1.
Principles
- Capture is the product. Not search, not synthesis, not chat. Get the thing into the system in one tap. Everything else is downstream.
- Future-you is the user. A note is only useful if you can find it in three months. Every design decision optimizes for that.
- Own your data. Storage lives in a git repository you choose — on your own disk, on your own remote. We never hold a copy.
- Spec first. Every substantive change starts as a requirements doc in the repo. Iron rules are enforced in code and tests.
- One door at a time. We'd rather ship one capture surface that's exquisite than five that are merely fine.
The company
Legal name (Chinese): 上海禧顶科技有限公司
Legal name (English): Shanghai Seii.top Technology Co., Ltd.
Registered office: Shanghai, China
Founded: 2026
Primary product: CaptureX (AI capture layer)
Website: https://seii.top/
We're a deliberately small team. If our principles resonate and you want to build with us, see the careers section on the contact page.