Overcollateralized Stablecoin Development with Collateralization
We took on a project where the protocol attracted $40M TVL in three months. On the fourth month, ETH dropped 35% in 4 hours—faster than the liquidation bot could process the queue. Several positions with a collateral ratio of 150% became undercollateralized before they were liquidated. The protocol minted unbacked stablecoins. That's exactly how systemic risk works in an overcollateralized stablecoin—not through contract hacks, but through an architectural flaw in the liquidation mechanics. Our experience developing such systems allows us to avoid these mistakes.
How does the liquidation system of an overcollateralized stablecoin work?
The hardest part in a CDP protocol is not the mint/burn itself, but the liquidation system under load. The classic scheme: if collateralRatio < liquidationThreshold, the position can be liquidated. The problem starts when the Chainlink price feed updates once per heartbeat (typically 1 hour or when deviation >0.5%), and the asset price drops faster.
During a flash crash with ETH -20% in 30 minutes, several things happen simultaneously: the on-chain price from Chainlink hasn't updated yet, the real price is already 18% below the oracle price, liquidation bots see positions as healthy based on on-chain data, and by the time the oracle updates, the liquidation queue becomes enormous. Gas wars between bots cause them to pay 200-500 gwei, and some positions simply don't make it.
Solution: a two-layer check—the primary Chainlink feed plus a Uniswap V3 TWAP as a sanity check. If the gap between them exceeds 5%, the protocol enters emergency mode with restrictions on new mints. This is what MakerDAO implemented through OSM (Oracle Security Module) with a 1-hour delay—not ideal, but gives governance time to react. Our design, as a Liquity alternative, improves upon existing liquidation mechanics.
Bad debt and coverage mechanism
In Liquity v1, during liquidation, the debt is covered from the Stability Pool. If empty, redistribution occurs among all vault holders, which can trigger a cascading chain reaction. In our implementation, we use an Insurance Fund formed from part of the liquidation penalty (10-13%). It covers first losses without shifting risk to governance token holders. Gas savings when using Dutch auction reach 30-50%. This approach enhances DeFi stablecoin security.
The problem of price manipulation via flash loans
Classic vector: take a flash loan, deposit it as collateral, mint stablecoin at an inflated price (if the oracle uses spot price from DEX), withdraw the stablecoin. TWAP closes this—manipulating spot price affects TWAP only if sustained over time. For new tokens with low liquidity, a whitelist with a liquidity threshold of $50M+ is necessary.
Why fork testing is critical for stablecoins?
No unit test can replace a fork test on real historical data. We test the protocol on scenarios: Black Thursday (ETH -55% in 24h)—checking the liquidation queue with zero liquidity in Stability Pool; LUNA/UST depeg—simulating fast collateral drop with rising sell pressure on the stablecoin; gas spike to 3000 gwei—checking economic incentive for liquidations. Foundry vm.createFork + vm.rollFork allows reproducing the exact state of mainnet at any point in history. Smart contract stablecoin audit is mandatory before mainnet deployment.
Step-by-step development of a CDP protocol
- Architecture design. Define storage layout, module interfaces, event schema for The Graph.
- Contract writing. Solidity 0.8.x with focus on gas optimization and security. Our Solidity stablecoin development follows best practices for security and efficiency.
- Comprehensive testing. Unit, integration, fork testing on historical scenarios, fuzz testing via Echidna with property-based invariant checks.
- External audit. Mandatory stage for CDP protocols with TVL > $1M.
- Deployment and management. Multisig via Gnosis Safe, timelock on critical parameters.
How we build an overcollateralized stablecoin
Contract architecture
We split the system into independent modules:
| Module | Responsibility | Upgradeability |
|---|---|---|
VaultManager |
Opening/closing positions, collateral accounting | UUPS |
PriceOracle |
Chainlink + TWAP aggregation, circuit breaker | Replaceable |
LiquidationEngine |
Liquidation queue, Dutch auction | UUPS |
StabilityPool |
Buffer for covering liquidations | Immutable |
StablecoinToken |
ERC-20 with mint/burn only from VaultManager | Immutable |
StablecoinToken is intentionally immutable—holders should not depend on governance changing token logic.
Dutch auction for liquidations
Instead of a fixed penalty, we use an auction: discount starts at 0% and increases each block until someone takes the position. Competition shifts to "who accepts a profitable price faster," and the protocol doesn't overpay liquidators. If the auction lasts longer than maxAuctionDuration without a buyer—the position moves to redistribution.
System parameters and governance
Key parameters to control:
| Parameter | Recommendation | Description |
|---|---|---|
| minimumCollateralRatio | 150% | Minimum collateralization level |
| liquidationPenalty | 10% | Penalty on liquidation |
| borrowingFee | 0.5-1% | Fee on mint |
| stabilityFee | 0-5% annual | Interest rate for usage (optional) |
Detailed parameter checklist
For new protocols, we recommend conservative settings: MCR 150%, penalty 10%, borrowingFee 1%. After accumulating on-chain history, parameters can be lowered via governance with a timelock.
What's included in the work
We offer turnkey development of an overcollateralized stablecoin: architecture design, contract writing, testing, audit from partners (Trail of Bits, Sherlock), documentation, multisig and timelock setup, team training. Our experience: 5+ years in DeFi, 10+ completed projects with TVL up to $100M. We have a proven track record and are trusted by top decentralized finance protocols. For a typical protocol with one collateral and Dutch auction, development budget starts at $50,000. We focus on stablecoin security to ensure resilience against attacks.
Development process
Analysis (3-5 days). Determine asset whitelist, system parameters, liquidation mechanics. Analyze competitors: Liquity, Gravita, Raft, Prisma.
Design (5-7 days). Storage layout, module interfaces, event schema for The Graph indexing.
Development (4-8 weeks). Contracts + comprehensive tests: unit, integration, fork tests on historical scenarios, fuzz tests via Echidna.
External audit (mandatory). At least one external audit for CDP protocols with potential TVL > $1M.
Deployment. Multisig via Gnosis Safe, timelock on changing key parameters (minimum 24-48 hours).
Time estimates
Minimal implementation (one collateral type, basic liquidation) — 6-8 weeks of development. Full protocol with multiple collaterals, Dutch auction, Stability Pool, and governance — 2-4 months including audit. Cost is calculated individually. Get a consultation on your project—we'll help you choose optimal parameters. Leave a request—we'll help you create a reliable and secure stablecoin.