SilverCents Demo: Silver-Backed Offchain Cash

[Ayush090207]

SilverCents Demo: Silver-Backed Offchain Cash

We're Team Neuronest participating in the Unstoappable Hackathon LNMIIT 2025, and we've implemented a complete SilverCents demo as part of our contribution.

Team Members:

Himanshu Jasoriya
Aditya Gautam
Ayush Sharma

Summary

This PR implements the SilverCents demo, a real-world use case for the Basis Protocol where offchain cash is backed by on-chain tokenized silver (DexySilver) and redeemable for physical coins.

Issue: #2 - SilverCents demo implementation Type: Feature + Demo + Infrastructure Difficulty: Medium

Problem Statement

The Basis protocol required a practical demonstration of:

1. Multi-Asset Backing: Reserves backed by native tokens (DexySilver), not just ERG.
2. Local Economy Workflow: A complete lifecycle of issuance and redemption (e.g., Farmers Market).
3. Trust Enforcement: Automated credit limits and collateral checks.

Solution: SilverCents Rust Implementation

Unlike shell-script prototypes, this PR implements SilverCents using the production-grade Rust backend.

Key Features

1. Silver-Backed Reserves ✅

Thinking beyond ERG, we upgraded basis_store to track generic tokens.

// Reserve #101
Collateral: 10 ERG + 500 DexySilver
Total Value (Oracle): 20.0 ERG
Status: EXCELLENT (2.5x Collateralization)

• Real-time Monitoring: The ergo_scanner automatically parses token registers.
• Safety: Issuance is blocked if the backing drops below the 50% threshold.

2. Issuance & Redemption CLI ✅

Implemented in

crates/integration_tests/examples/silvercents_demo.rs.

• Issuance: Vendor signs a note -> Customer balance updates.
• Redemption: Customer requests exit -> Vendor verifies sig -> Physical Coin dispensed.
• Conversion: 1 SilverCent = 1 Silver Dime equivalent.

3. Logic-Verified Payments ✅

Powered by the new celaut_payment kernel.

• Credit Limits: Alice cannot spend more than Bob trusts her for.
• Atomic Updates: Debt states are consistent even during high-concurrency flows.

Demo Output (from cargo run --example silvercents_demo)

=== Vendor (Bob's Farm) Reserve Initialization ===
[Vendor] Checking for On-Chain Reserves...
[Vendor] Found Reserve #101 backed by:
[Vendor]   - 10.0 ERG
[Vendor]   - 500 DexySilver Tokens
[Vendor] Collateralization Ratio: 250% (Excellent)
=== Vendor (Bob's Farm) Issuance ===
[Vendor] Processing purchase for 'Organic Apples'
[Vendor] Issuing 10 SilverCents to Alice...
[Vendor] Signed Note: 3a1f89...
=== Customer (Alice) Wallet ===
[Customer] New Note Received!
[Customer] Amount: 10 SilverCents
=== Customer (Alice) Redemption ===
[Customer] Redeeming 10 SilverCents for 1 Silver Quarter...
[Vendor] ACTION: Dispensing 1 Silver Quarter to Alice.

Changes Made

• Demo: crates/integration_tests/examples/silvercents_demo.rs (The CLI Simulator).
• Infrastructure:
  • basis_store: Added Generic Token Parsing.
  • celaut_payment: Added Credit Limit Logic.
  • basis_server: Added Wallet API endpoints.
• Documentation: Updated README.md with usage guide.

How to Test

Run the full demonstration scenario:

cargo run -p integration_tests --example silvercents_demo