Last weekend, JSC sponsored EthTokyo Hackathon with a total prize pool of $3500. This post is the first in a three-part series where we will highlight each winning team, their winning solution, why we awarded them the respective prize, and the winning team’s feedback to JSC.
JSC sponsored the following hackathon tracks:
-
Compliant, Privacy-Preserving DeFi application (
Winner prize: 
US$1500) -
Ticketing application (
Winner prize: US$1500) -
One Special Award (US$500) for a unique idea that, while not fully developed into a winning solution for (1) or (2), strongly resonates with JSC’s mission of creating “magical” user experiences on web3.
We awarded zkIoT JSC’s “Special Award” prize for their clever application of “Mizuhiki Verified” (Proof of KYC) to help enterprises create autonomous machine interactions (see: object-capability model) as well as share information with authorised entities and individuals. We believe that zkIoT developed tooling that directly addresses some of the core pain-points Japanese infrastructure providers face. Manufacturing in particular is a critical and successful industry in Japan, but needs innovation to remain competitive globally. JSC is committed to helping the overall Japanese ecosystem and economy by creating “magical” user experiences on web3.
According to the team, “zkIoT (acronym for “Zero-knowledge Internet of Things”) is a framework that enables IoT devices to prove compliance with rules and thresholds without revealing raw sensor data. By applying zero-knowledge proofs to physical sensor outputs, industries can unlock trust and data usability while protecting privacy, trade secrets, and operational know-how.”
We see zkIoT’s solution as a pivotal step for Japanese manufacturers and physical infrastructure providers, where supply-chain processes and climates can be properly audited and attested for in a verifiable manner. For example, a major national data center could be verifiably proven to be running at optimal temperatures, without revealing process IP addresses, routes, or raw sensor logs. Most importantly - and this is the core “web3 feature-add” - this information can be shared with KYCed/KYBed third-parties and intermediaries in a seamless and verifiable manner.
JSC’s vision partners span multiple industries, including telecommunications, advertising, and manufacturing. We see a lot of potential in the crossover between IoT and blockchain, although we also believe the “right” solution will be very technically challenging to build. We were pleasantly surprised when we saw that zkIoT’s solution had considered the privacy and secrecy elements critical to these industries, as well as the need for compliance, verifiability, trust, and information-sharing. We believe their highly technical solution was especially impressive, given the 48 hour timeframe of the hackathon.
On Using Mizuhiki Verified Soulbound Tokens (SBTs)
zkIoT used Mizuhiki SBTs as an identity anchor, which could bind organizations, production lines, and devices to a non-transferable on-chain identity, making it possible to verify “who produced or handled this.”
Mizuhiki SBTs could also enable policy and allowlists, where machine interactions are gated by SBT ownership—for example, only SBT-holding (i.e., KYC’ed) devices or vendors would be able to accept jobs, trigger payments, or unlock access.
When presenting to JSC judges on the hackathon weekend, zkIoT expressed an interest in a SBT for KYB (currently, the Mizuhiki Verified SBT is only a proof of KYC as per Japan’s AML/CFT law), which is something the JSC dev team are currently looking into.
Takeaways
zkIoT’s hackathon project was not a simple one: combining zero knowledge proofs, blockchain, off-chain verifiability (using AI, nonetheless…), and on-chain compliance gating, is not a mission for the faint of heart. Upon reflection, the team stated: “we realized that it is far more valuable to prove one high-value claim well than to try to cover everything in a limited time. By delivering a thin yet reliable pipeline—sensor → ZK proof → voucher → mint—we could present something that actually works, and that insight connects directly to future real-world applications.”
Their comments regarding their ETHTokyo hackathon experience were heart-warming:
“We appreciated the support from the JSC team. The team was proactive in walking around and checking in with participants, ensuring that all developers had what they needed to continue building. This attentiveness created a supportive environment and made the hackathon experience smoother and more enjoyable. We also felt, during our presentation, that the JSC team has a deep understanding of the Japanese market, which gave us confidence that our idea was being evaluated with meaningful local context.”
Thank you again to zkIoT for an excellent submission, and we very much look forward to working with you in the near future 
Links
GitHub Link to zkIoT’s project: https://github.com/Jun0908/zkiot
