KOLO

Purpose-locked USDC savings vaults on Arc. Save small-small toward a real goal; anyone anywhere tops up your vault; when it fills it doesn't hand you cash — it executes its purpose (pays the school, the bill, the rent).

contracts/   Solidity vaults + factory — compiled clean, 24/24 e2e passing
backend/     NestJS — Arc indexer, auto-executor, settlement pipeline, REST API
frontend/    your UI goes here

Quickstart

# 1. Contracts — compile & test locally
cd contracts && npm install && npm run compile
anvil --chain-id 5042002 &          # https://getfoundry.sh
npm test                            # 24 assertions, 6 scenarios

# 2. Deploy factory to Arc Testnet
cp .env.example .env                # PRIVATE_KEY (fund at faucet.circle.com)
npm run deploy:arc                  # prints factory address + arcscan link

# 3. Backend — infra, then run
cd .. && docker compose up -d       # postgres + redis
cd backend && npm install
cp .env.example .env                # FACTORY_ADDRESS + EXECUTOR_PRIVATE_KEY
npm run prisma:generate && npm run prisma:migrate
npm run start:dev                   # API :3001 + indexer + workers

# 4. Point the factory's executor at the backend key (once, from owner key):
#    factory.setExecutor(<backend executor address>)

How the pieces talk

UI → POST /purpose-ref (bill payload → purposeRef) → user signs factory.createVault(...) → funding link shared → contributors approve + contribute (or relayer contributeFor for cross-chain) → indexer sees goal reached → executor auto-calls execute() → funds hit settlement treasury → settlement worker pays the bill via BillerAdapter → funding page shows SETTLED with biller reference.

Full architecture, invariants and conventions: CLAUDE.md (Claude Code reads it automatically).