Yearn Pricing Service

A high-performance TypeScript pricing service that aggregates token prices from multiple DeFi protocols and external sources for Yearn Finance ecosystem.

Price Discovery Process

1. Token Discovery: Automated discovery from multiple protocols

   • Scans protocol registries and factories
   • Identifies LP tokens, vault tokens, and derivatives
   • Maintains a comprehensive token registry

2. Price Fetching: Multi-source price aggregation

   • Primary: DeFiLlama API for broad coverage
   • Secondary: On-chain oracles (Lens Protocol)
   • Tertiary: Protocol-specific calculations
   • Fallback: Direct DEX pool queries

3. Caching Strategy:

   • In-memory cache with configurable TTL
   • Optional Redis for distributed deployments
   • Persistent file storage for recovery
   • Chain-specific cache isolation

Configuration

Environment Variables

See the .env.example file in the root directory:

RPC_URI_FOR_1=
RPC_URI_FOR_10=
RPC_URI_FOR_100=
RPC_URI_FOR_137=
RPC_URI_FOR_146=
RPC_URI_FOR_250=
RPC_URI_FOR_8453=
RPC_URI_FOR_42161=
RPC_URI_FOR_747474=

# Redis Configuration
STORAGE_TYPE=redis
UPSTASH_REDIS_REST_URL=
UPSTASH_REDIS_REST_TOKEN=
REDIS_LOAD_BACKUP=false

# Logging
LOG_LEVEL=debug

Development

bun run refresh           # Run token discovery and price refresh for all chains
bun run refresh <chainId> # Run token discovery and price refresh for a specific chain
bun vercel                # Run local Vercel development server

bun run lint              # Check code style
bun run lint:fix          # Fix code style issues
bun run format            # Format code with Biome

Refreshing Prices

You can refresh prices for all chains or a specific chain:

# Refresh all chains
bun run refresh

# Refresh only Ethereum (chain 1)
bun run refresh 1

# Refresh only Optimism (chain 10)
bun run refresh 10

This is useful for testing and debugging specific chain configurations without waiting for all chains to complete.

Vercel Deployment

# Deploy to Vercel
bun run deploy

API Endpoints

All endpoints maintain compatibility with the original Go implementation:

Get All Prices

GET /prices/all

Returns prices for all tokens across all supported chains.

Query Parameters:

Get Chain Prices

GET /prices/:chainID

Returns all prices for a specific chain.

Get Chain Prices (Detailed)

GET /prices/:chainID/all
GET /prices/:chainID/all/details

Returns detailed price information for all tokens on a chain.

Get Single Price

GET /prices/:chainID/:address

Returns the price for a single token.

Get Multiple Prices

GET /prices/:chainID/some/:addresses

Returns prices for multiple tokens on a specific chain. Addresses should be comma-separated.

Get Cross-Chain Prices

GET /prices/some/:addresses

Returns prices for tokens across all chains.

Batch Price Request

POST /prices/some

Request body:

{
  "addresses": ["0x...", "0x..."],
  "chainIds": [1, 137] // optional, defaults to all chains
}

Supported Chains

• Ethereum (1)
• Optimism (10)
• Gnosis/xDai (100)
• Polygon (137)
• Fantom (250)
• Base (8453)
• Arbitrum (42161)
• Katana (747474)

API Response Format

Standard Price Response

{
  "0x...": 1234.56,
  "0x...": 0.9876
}

Detailed Price Response (/details endpoints)

{
  "0x...": {
    "price": 1234.56,
    "source": "defillama",
    "timestamp": 1699123456,
    "confidence": 0.99
  }
}

License

MIT License - see LICENSE file for details