touchgrass

Demo

About

### **touchgrass: Run, Explore, and Mine the Real World** **touchgrass** is a gamified running app that turns outdoor activity into an on-chain data mining experience. When users go out for a run, they **stream their GPS coordinates through Yellow Network’s state channels**. This live, off-chain stream forms the backbone of a session — allowing real-time location updates, multiplayer awareness, and low-latency gameplay. While running, users can **“mine” datacoins** by completing *real-world data quests*: spotting potholes, EV chargers, water fountains, or any valuable urban dataset. Each quest represents a small “data job” — when a user submits a photo and proof, the app packages it into a **ZK-TLS attestation** (zero-knowledge time-location proof) and sends it to the backend for validation. A lightweight **LLM validator** checks the submission (e.g., “is this really a pothole?”) and confirms the claim’s accuracy. If the data is valid, the event is emitted through Yellow’s state channel as a **datacoin capture**, and the runner is rewarded with a minted **datacoin** NFT — representing a verifiable, user-contributed data point anchored to the real world. When the user presses **STOP**, the session closes: * The **final state** (distance, route, and validated datacoin captures) is **settled on-chain** via Yellow’s channel settlement. * The datacoins mined during the session become claimable on-chain assets, each tied to a verifiable proof of work (running + data capture). On the frontend, a **Mapbox-powered interface** visualizes everything live: * active runners around you (via Yellow’s real-time state feed) * datacoin markers appearing as users mine real-world data * a leaderboard that aggregates who has contributed the most verified data Under the hood: * **Next.js web app** for frontend * **Yellow Network state channels** for real-time GPS streaming and off-chain state consensus * **LLM validator service** for automatic data quality checks * **ZK-TLS proofs** for privacy-preserving location attestation * **Datacoin smart contract** for on-chain minting and reward settlement * **MongoDB** for persistence (runs, users, datacoins, proofs) --- ### **Why this matters** touchgrass transforms outdoor movement into a decentralized sensing network. Instead of mining digital blocks, runners **mine physical data** — building an open, verified map of real-world insights: where potholes exist, where clean water points are, where EV chargers work. Every step becomes a datapoint, and every verified submission turns into a tokenized contribution to a collective data layer. In short: **touchgrass** bridges *movement*, *data provenance*, and *decentralized rewards* — powered by **Yellow’s state channels** for real-time off-chain interaction and on-chain finality.

How it's made

touchgrass is built as a **Next.js web app** that uses **Yellow Network state channels** to stream real-world movement data and **Lighthouse’s Datacoin SDK** to mint verifiable, rewardable consumer data assets. When a runner hits **START**, their GPS coordinates begin streaming through a **Yellow clearnet state channel** to our backend peer. This off-chain state channel provides a low-latency, verifiable stream of location updates while keeping everything off-chain until the session ends. The backend aggregates those updates, anchors them in **MongoDB**, and broadcasts live map changes to nearby players in real time. While running, users can complete **data quests** — such as mapping potholes, EV chargers, or water fountains. When a user submits a photo, the backend uses **Reclaim Protocol’s zkTLS proofs** to attest to location and time without revealing sensitive GPS data. We then run a lightweight **LLM-based validator** to verify the content of the submission (for example, confirming that the image truly contains a pothole). If the data is valid, we mint a **Datacoin** using the **Lighthouse SDK** — encoding the data’s proof, metadata, and contributor wallet into a verifiable token on-chain. Each Datacoin represents a useful, privacy-preserving, user-contributed data point that can be queried or traded later as part of an open data economy. When the runner presses **STOP**, the Yellow state channel finalizes the session: * the off-chain state (distance, movement, mined datacoins) is **settled on-chain**, * rewards are distributed to the user’s wallet, * and the data contributions are finalized via Lighthouse’s Datacoin protocol. The frontend uses **Mapbox GL JS** for live visualization — showing nearby runners, mined datacoins, and verified quest markers — while the backend (Node + MongoDB) maintains persistent state and proof data. We also added a **JS-based lat/lon bucketing system** to map territory and manage channel routing efficiently across the world. **Stack summary:** * **Next.js** for the web app UI * **Yellow Network** for off-chain state channels and realtime GPS sync * **Lighthouse SDK** for Datacoin minting * **Reclaim Protocol + zkTLS** for privacy-preserving proof-of-location * **LLM Validator** for content validation * **MongoDB** for persistence * **Mapbox GL JS** for the live interactive map **Notable hack:** We cached Mapbox tile hashes locally to generate deterministic zkTLS proofs quickly, allowing near real-time Datacoin minting from field data without repeated external API calls.