Backers get automatic refunds if the goal is not reached
Intermediate16h1–2
SolidityFoundryWagmi
17/20Onchain Savings Circle
Run a rotating savings circle with transparent rules in a smart contract.
Advanced26h2–3 people17/20 fit
Build Onchain Savings Circle for community savings groups in ~26h with 2–3 people. Stack: Solidity + Foundry + Wagmi.
Why it wins: Brings a traditional finance practice onchain.
Build flow
01 · Problem
Informal savings circles depend on trust and break when someone defaults.
02 · Solution
Members deposit stablecoins each round, a contract pays out in rotation and tracks contributions, with collateral to discourage default.
03 · Build
- 1Write the contract
- 2Test with Foundry
- 3Build UI
- 4Simulate rounds
04 · Demo
Run three rounds on a testnet with four wallets.
MVP checklist
- Rotation payouts
- Contribution tracking
- Collateral
- Member dashboard
Tech stack
| Tech | Role | |
|---|---|---|
| Solidity | Smart contracts | Chain |
| Foundry | Contract testing + deploy | Chain |
| Wagmi | React wallet hooks | Chain |
Reference repos
Open-source projects you can build on. Links checked 2026-10-31.
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