> ZK-ROSCA · Midnight Network · Est. 2026
Save Together.
Stay Private.
The world's first ZK-ROSCA — a privacy-preserving savings circle where contributions are anonymous, payouts enforced by code, and credit built on-chain.
> Market Context
The market is enormous.
The problem is unsolved.
> Protocol Architecture
Built for privacy.
Designed for scale.
Zero Knowledge
Your contributions are invisible
ZK proofs on Midnight Network ensure no one — not other members, not validators, not even Kosh — can see how much you contribute. Only the proof of compliance is public.
Smart Contracts
Code enforces the rules
No informal trust. Smart contracts manage every contribution cycle, payout rotation, and default condition.
ZK Credit
Build reputation without exposure
Every completed circle generates a ZK credit proof. Prove your reliability to future circles — without revealing your history.
Global Access
ROSCAs are everywhere. Now they're on-chain.
500M+ people participate in savings circles globally — chit funds, tandas, stokvels. Kosh is the first protocol to bring this $500B+ informal market on-chain with cryptographic guarantees.
Midnight Network
Privacy-first blockchain
Built exclusively on Midnight — the only L1 designed for private smart contracts by default.
Open Protocol
Composable & auditable
Kosh is a protocol, not a product. Any app can build ROSCA mechanics on top. Compact ZK circuits are publicly auditable.
> ROSCA Lifecycle
How a ZK-ROSCA works
A ROSCA is a rotating savings and credit association — the oldest form of collective saving. Kosh adds ZK proofs, smart contract enforcement, and on-chain credit without removing any of the trust that makes it work.
Launch a circle
Set the number of members, contribution amount, cycle length, and payout order. Deploy a smart contract with one click.
// Your parameters are public. Your identity is optional.
Invite members
Members join by submitting a ZK proof of identity — proving eligibility without revealing who they are.
// No KYC database. No identity exposure.
Fund each cycle
Every period, members contribute their share. ZK proofs verify payment without revealing the amount or the sender.
// Contributions are cryptographically anonymous.
Get the payout
One member receives the full pool each cycle — chosen by the pre-agreed rotation or a fair on-chain lottery.
// Payouts are automatic. No middleman. No delay.
Handle non-payment
If a member misses a contribution, the smart contract enforces the pre-defined default rule automatically.
// No social enforcement needed. Code handles it.
Build your ZK credit
Completing a full circle generates a ZK credit proof — a portable on-chain record of reliability.
// Use it for future circles. Keep your history private.
> Chain Selection
Why only Midnight can do this
Privacy is the default, not an add-on
Every other blockchain makes privacy optional and expensive. Midnight flips this: privacy is the base layer. ZK-ROSCAs require invisible contributions by design — Midnight is the only chain where that's possible without heroic engineering.
Compact ZK circuits, not hacked workarounds
Midnight's Compact language is purpose-built for ZK circuit development. Writing ZK proofs for ROSCA contribution verification on any other chain would take years. On Midnight, it's the intended use case.
Compliance without surveillance
Midnight's dual-state model separates public commitment data from private transaction data. This means regulators can verify aggregate compliance without accessing individual user data — a critical property for global ROSCA rollout.