APY/APR Comparison System for DeFi Protocols

APY/APR Comparison System for DeFi Protocols

A user sees 4.2% APY on Aave USDC, 5.1% APR on Compound, and 5.8% with MORPHO rewards on Morpho. These numbers are incomparable: Aave uses compound interest, Compound uses simple rate, and Morpho adds token rewards. On a DeFi aggregator project, we found that data providers mixed APY and APR, and rewards distorted the picture by up to 7%. After normalization and implementing a risk-adjusted score, the client increased their pool's TVL by 35% due to accurate yield display—that's 3x better than raw APY sorting. The system also saved the team 15 hours per week (approx. $3,000/month or $36,000/year) of manual analysis, allowing faster reaction to market changes.

We built a system that normalizes all metrics to a unified standard—Daily APR—and displays real yield accounting for all factors. It relies on on-chain data, Multicall3 batching, and historical aggregation. In practice, differing yield representations can mislead even experienced LPs. Correct normalization is the first step toward objective pool comparison.

The Problem of Metric Comparison

APR is a simple rate without reinvestment. APY accounts for compounding. The difference is significant with frequent compounding:

APY = (1 + APR/n)^n - 1

On Ethereum, with 10% APR and compounding every block (~2190 times/year), APY ≈ 10.52%. For correct comparison, the system normalizes everything to Daily APR—dividing the annual rate by 365. The user sees APY, but internally we use Daily APR.

Many protocols also pay native tokens (COMP, AAVE, MORPHO) on top of the base rate. We show base APY (without rewards) and total APY (with rewards) separately. For reward tokens, we factor in the current price via oracles (Chainlink)—volatile, may drop by claim time, vesting/locks (AAVE Safety Module vests for 10 days), and emission decay. The user decides whether to include unstable rewards.

Fetching on-chain data: each protocol provides data differently. We use Multicall3 for batching: 1000 individual calls packed into one transaction. This is 100 times more efficient than sequential requests and saves gas.

Example for Aave V3:

const calls = protocols.flatMap(protocol => 
  assets.map(asset => ({
    target: protocol.address,
    callData: protocol.interface.encodeFunctionData("getReserveData", [asset])
  }))
);
const results = await multicall.aggregate(calls);

For historical data, we use official subgraphs (The Graph) for Aave, Compound. For protocols without subgraphs, we build a custom event indexer.

System Architecture

Data Collection Layer

On-chain calls are expensive (RPC requests). With 10 protocols × 20 assets × 5 metrics = 1000 calls per update. Solution: Multicall3 batching—all calls in one transaction. What our work includes:

• Development of adapters for each protocol (standard contracts + custom)
• Caching setup: Redis (TTL 60s) for current rates, PostgreSQL for hourly snapshots
• Real-time updates via WebSocket (when events are available)
• Background job every 60 seconds fetches on-chain data

How We Guarantee Metric Accuracy

We verify formulas against official protocol documentation—Aave docs, Compound docs. Each adapter passes unit tests using Tenderly fork. Results are cross-checked with Etherscan and Dune Analytics.

Historical Dynamics

Current APY is a snapshot. For decision-making, history is needed: moving averages (7d, 30d), volatility (std dev of APY), min/max over period. A volatile APY (5x range in a month) is a different risk profile than a stable APY (±0.5%). Example volatility calculation: over 30 days, APY ranged from 3.2% to 7.8%. Standard deviation = 1.4%. This signals unstable yield, often due to reward emissions.

Ranking and Comparison

Simply sorting by APY is not enough. The system offers filters:

• Only stable APY (volatility < 0.5% over 30 days)
• Only audited protocols (verified audits)
• Minimum TVL (exclude small pools)

The user weighs priorities—no single score is imposed.

Which Protocols Are Supported by Default?

We support major lending markets and pools:

On request, we add any EVM protocol with a custom adapter.

Step-by-Step APY Normalization

1. Fetch raw data from protocol contracts via Multicall3 (single batch transaction).
2. Extract base rate and reward parameters (reward per second, oracle price).
3. Convert to unified format: convert APR to APY using the protocol's compounding frequency.
4. For reward tokens, compute total APY considering current price and vesting.
5. Write snapshot to historical database and update Redis cache (TTL 60s).
6. Expose normalized metrics via REST API.

This process repeats automatically every minute.

What's Included in the Work

• Adapters for each protocol (standard + custom)
• REST API with documentation (OpenAPI)
• Historical index (hourly snapshots in PostgreSQL)
• UI components for Next.js (Recharts, TanStack Query)
• Unit and integration tests using Tenderly fork
• Deployment and operation manual
• 30-day post-launch support

Tech Stack

• Backend: Node.js + TypeScript, Viem (on-chain), PostgreSQL, Redis, Bullmq
• Frontend: Next.js, TanStack Query, Recharts / Tremor
• Infrastructure: Docker Compose, GitHub Actions, Tenderly for forking

Timelines: MVP with 3-5 protocols and current rates—3-5 days. Full system with history, filters, and visualization—2-3 weeks. Typical implementation costs range from $5,000 to $15,000 depending on complexity. Contact us to evaluate your project. Request a demo to see normalized metrics for your protocols.

Our expertise: With 5+ years in Web3 development and 50+ integrated DeFi protocols, we deliver accurate yield normalization. We have completed 30+ projects for clients ranging from startups to established protocols. Our team ensures calculation correctness and on-chain data accuracy.

DeFi Protocol Development

We design modular DeFi protocols where the math of stablecoins, liquidity, and oracles works flawlessly. Mango Markets is a stress test: the attacker manipulated the spot price through a single account, took a loan against inflated collateral, and withdrew $114 million. The oracle took the price from a single source without TWAP. Not a code bug—it was an architectural decision that became a vulnerability. Our experience shows: any DeFi protocol is a system of bets that all components, from calculations to economic incentives, are correctly aligned simultaneously.

We don't write code under the 'if it works, don't touch it' mindset. We model stress scenarios: cascading liquidations, depegs, flash loans. Only then do we build events that won't break the protocol.

Why are oracles a critical component of DeFi?

Most major DeFi hacks started with oracle manipulation. Let's break down the three layers we use in every project.

Spot price as oracle—not an option. Uniswap v2 spot price can be shifted by a flash loan in one transaction. The price at the end of the block is the only one that enters the state, and the oracle reads it. Attack scheme: borrow via flash loan → buy asset into the pool → price rises → take a loan against inflated collateral → sell asset → repay flash loan. One transaction.

TWAP as protection. Uniswap v3 observe() averages the price over a period (30 minutes). Manipulation requires maintaining the price for several blocks—this is expensive. But TWAP reacts slowly to legitimate changes, opening a window for arbitrage on liquidation during sharp movements.

Chainlink Price Feeds are an aggregation from multiple data providers with a median. Standard for lending. Problem: heartbeat 1–24 hours and deviation threshold 0.5%. If the price doesn't move, the feed may not update for a day. In volatile markets—lag.

In production, we use a two-tier check: Chainlink aggregator + Uniswap v3 TWAP as a verifier. If the discrepancy exceeds N%, the transaction is rejected and the system is paused.

How to protect a DeFi protocol from flash loan attacks?

Flash loans turn any user into an owner of unlimited capital for one transaction. Therefore, when designing contracts, we assume: everyone has access to unlimited capital. This completely changes the threat model.

Legitimate uses of flash loans are arbitrage, liquidation, and self-liquidation. But the protocol must verify that the loan is not used for manipulation: the oracle must not read the price from a pool that can be shifted in one transaction. We add checks on block.timestamp and minimum liquidity depth.

Key Components of DeFi Architecture

AMM: From x*y=k to Concentrated Liquidity

Uniswap v2 uses x * y = k. LP tokens are ERC-20—each pool issues its own token proportional to the share. Problem: liquidity is spread across the entire curve, most of it unused.

Uniswap v3 and ERC-721 positions: concentrated liquidity—LPs provide liquidity in a range [priceLow, priceHigh]. Capital efficiency up to 4000x for stable pairs. But ERC-721 breaks vault strategies built for ERC-20. Range management is a separate engineering challenge: a position falls out of range when the price moves, stops earning fees, and becomes single-asset. Protocols like Arrakis Finance automatically rebalance. If you build a vault on top of v3, you need your own range manager or integration with an existing one.

Slippage in v3 is calculated via sqrtPriceX96—96-bit fixed-point math. Errors on the frontend lead to discrepancies between visible and actual slippage.

Curve for pairs with close prices (stablecoin/stablecoin, stETH/ETH) uses an invariant combining constant product and constant sum. Lower slippage within the peg range. Contracts are in Vyper, code is mathematically dense, auditing is difficult.

Lending Protocols: Collateral, Liquidation, Bad Debt

LTV defines the maximum loan against collateral. Liquidation threshold is the level for liquidation. The difference is the buffer for the liquidator. Typical example: LTV 75%, liquidation threshold 80%, bonus 5%. If the price drops 20%+, the position is open for liquidation.

Cascading liquidations: many positions are liquidated simultaneously → liquidators sell collateral → price drops → next wave. LUNA/UST 2022 is a classic cascade.

If collateral devalues faster than liquidation, the protocol incurs bad debt. Aave uses a Safety Module (staked AAVE), Compound uses reserves. Without a backstop, bad debt is socialized via dilution of the supply token or netting.

Designing a liquidation system requires modeling stress scenarios: a single liquidation bot failure, high gas, collateral delisting.

Yield Farming and Incentive Mechanics

Liquidity mining distributes governance tokens to LP providers. Problem: mercenary capital—farmers come, sell tokens, leave. TVL is illusory.

Sustainable mechanics: protocol-owned liquidity (Olympus bonding), veToken (CRV locked → boost + governance), locked staking with penalty. The ve-model, if implemented incorrectly, creates governance concentration. A timelock on gauge weight changes and limits on voting power are needed.

What Our DeFi Protocol Development Includes

• Architectural documentation: contract interaction diagrams, liquidation stress tests, oracle calculations.
• Implementation in Solidity 0.8.x with OpenZeppelin 5.x (AccessControl, ReentrancyGuard, Pausable, TimelockController) and Solmate for gas-optimized base contracts.
• Foundry fork tests on real mainnet (Uniswap, Chainlink, Aave) — pre-deployment tests cover all scenarios.
• Audit: at least two independent auditors for TVL over $1M. Code4rena or Sherlock for bug bounty.
• Deployment with Gnosis Safe 3/5 multisig + timelock 48–72 hours.
• Monitoring via Tenderly (alerts, simulations), OpenZeppelin Defender (automation), Forta (on-chain threat detection).
• Post-launch support: updates, patches, upgrades via proxy.

Our Expertise and Experience

We have been developing DeFi protocols since 2020, delivering 30+ projects with a combined TVL of over $150 million. Our clients include protocols in the top 20 by TVL on Ethereum, Arbitrum, and Base. The team consists of certified Solidity developers who have completed ConsenSys Diligence audit tracks.

DeFi basic principles that we apply in practice.

Timelines

• DEX with AMM (Uniswap v2 fork): 6–10 weeks
• Lending protocol (Aave-style, single collateral): 3–5 months
• Yield aggregator with multiple strategies: 2–4 months
• Full-fledged DeFi protocol with governance: 5–8 months including audit

Cost is calculated individually—contact us for a project estimate.

Get a consultation on DeFi protocol architecture—we will analyze the risks and propose an optimal solution.