Company
About SynthesisUI
SynthesisUI is a frontend governance platform - the accountability layer between your design system and the agents that build with it. It reads the code a team already has, compiles it into a design system that machines can read, and then checks what ships against it.
What we build
Software teams now write a large share of their interface with AI coding agents. The agents are fast and they are fluent, and that is exactly the problem: nothing downstream of them knows what this particular company's product is supposed to look like, so every new screen drifts a little further from the last one. The gap is not creation. It is verification.
SynthesisUI closes it in three moves. It reads an existing repository and measures how it really builds interface, component by component. It compiles what it finds into blueprints: executable recipes that carry a component's structure, its variants, the design tokens it is allowed to use, and the rules that govern it. And it governs what happens next, auditing new code against those blueprints and reporting drift as a number instead of a surprise.
Everything lands in a folder the customer owns, readable by any coding agent, and deleting the folder is how you leave. We sell the check, not the lock-in.
Who we are
SynthesisUI is built by Mauricio Massaaki, a software engineer in Sao Paulo, Brazil, and operated by Syntxs Labs, the trading name of M. Massaaki Tech Ltda. The company is registered in Brazil and active; its registration number is below and can be checked against the Brazilian federal registry.
We are not in stealth mode. The product is public, the design system gallery is open to browse, the command-line tool is published on npm, and anyone can audit their own repository with it for free, without an account.
Company details
- Legal name
- M. Massaaki Tech Ltda
- Trading as
- Syntxs Labs
- Company registration (CNPJ)
- 68.248.380/0001-11
- Incorporated
- July 23, 2026
- Headquarters
- Sao Paulo, SP, Brazil
- Product
- SynthesisUI
- Contact
- massaaki@synthesisui.com
Contact
Press, partnerships, data handling and anything else, all to the same place: massaaki@synthesisui.com. It reaches the founder directly. The privacy policy and terms of use say the rest.