stablecoin-yield

The official Barker JS/TS SDK for stablecoin yield data — real-time APY/TVL from 500+ DeFi protocols across 40+ chains, plus market overview and historical APY trend vs US Treasury. Zero dependencies, Node 18+.

Powered by Barker — The Stablecoin Yield Map.

npm install stablecoin-yield

Quick Start

import { getVaults, formatApy } from 'stablecoin-yield';

// Top 5 USDC yields right now
const vaults = await getVaults({ asset: 'usdc', sort: 'apy', limit: 5 });

for (const v of vaults) {
  console.log(
    `${v.protocolName} (${v.chainName})  ${formatApy(v.supplyApyTotal)}  $${v.supplyTvl.toLocaleString()}`
  );
}
//  Sky (Ethereum)  3.75%  $6,350,244,063
//  Aave (Arbitrum) 3.42%  $1,210,455,028
//  ...

API Surface

Default client (zero config)

The simplest path — uses the public Barker API, no key required.

import { getVaults, getMarketOverview, getMarketTrend } from 'stablecoin-yield';

const vaults = await getVaults({ asset: 'usdc', sort: 'apy', limit: 10 });
const overview = await getMarketOverview();
const trend = await getMarketTrend({ days: 30 });

Custom client

For custom config (timeouts, base URL, alternate fetch), instantiate Barker.

import { Barker } from 'stablecoin-yield';

const barker = new Barker({
  baseUrl: 'https://api.barker.money/api/public/v1',  // default
  timeoutMs: 5_000,                                    // default 10000
  // fetch: customFetch,                               // optional
  // userAgent: 'my-app/1.0',                          // optional
});

const vaults = await barker.getVaults({ minTvl: 1_000_000, limit: 20 });

Error handling

All non-2xx responses, timeouts, and success: false payloads throw a BarkerApiError.

import { getVaults, BarkerApiError } from 'stablecoin-yield';

try {
  const v = await getVaults({ asset: 'usdc' });
} catch (err) {
  if (err instanceof BarkerApiError) {
    console.error('Barker API failed:', err.status, err.endpoint);
  } else {
    throw err;
  }
}

Methods

getVaults(options?) → DefiVault[]

Real-time DeFi yield pools, sorted by APY (default).

Options:

| Field | Type | Description | |---|---|---| | asset | string | Stablecoin symbol filter, e.g. 'usdc', 'usdt', 'dai' | | chain | string | Chain filter, e.g. 'ethereum', 'arbitrum', 'base' | | protocol | string | Protocol uid filter, e.g. 'aave', 'compound' | | sort | 'apy' \| 'tvl' | Default: 'apy' | | order | 'asc' \| 'desc' | Default: 'desc' | | limit | number | Max items | | offset | number | Pagination offset | | minTvl | number | Minimum TVL in USD (excludes tiny exotic pools) |

Returns DefiVault[] with camelCase fields — see index.d.ts for the full type. APY fields are decimal (see "APY units" below).

getMarketOverview() → MarketOverview

Total stablecoin market cap, asset/chain distribution, summary.

const ov = await getMarketOverview();

console.log(`Total: $${(ov.stablecoinMcap.total / 1e9).toFixed(1)}B`);
console.log(`Yield-bearing: $${(ov.stablecoinMcap.yieldBearing / 1e9).toFixed(1)}B`);

for (const a of ov.assetDistribution.slice(0, 5)) {
  console.log(`  ${a.assetSymbol}: ${(a.sharePct * 100).toFixed(1)}% of TVL`);
}

getMarketTrend({ days? }) → MarketTrendPoint[]

Historical APY trend (avg / median / TVL-weighted) with US 3-month Treasury benchmark.

const trend = await getMarketTrend({ days: 30 });
const latest = trend.at(-1)!;

console.log(`Median DeFi: ${formatApy(latest.medianApy)}`);
console.log(`US Treasury 3m: ${formatApy(latest.treasuryYield3m)}`);
console.log(`Spread: ${formatApy(latest.medianApy - latest.treasuryYield3m)}`);

APY units — the one rule

All APY fields returned by the API and this SDK are decimal, where:

• 0.0523 means 5.23%
• 0.10 means 10%
• 3.0007 means 300.07% (a campaign pool, not a typo)

This matches Barker's internal storage. The trap to avoid: don't divide by 100 again when you see a value ≥ 1 — it's already a multiplier, not a percentage.

Use the built-in helpers to stay safe:

import { apyToPct, pctToApy, formatApy } from 'stablecoin-yield';

apyToPct(0.0523);      // 5.23   (decimal → percent number)
pctToApy(5.23);        // 0.0523 (percent number → decimal)
formatApy(0.0523);     // "5.23%"
formatApy(0.0523, 1);  // "5.2%"
formatApy(null);       // "—"

Public API limits

• Rate limit: 30 req/min per IP
• Auth: none — fully public read-only
• Sensitive data: never sent. Only public market parameters (symbol, chain, sort, limit) leave your machine.

Need higher limits, CEX per-venue detail, or historical raw data? See app.barker.money/enterprise.

TypeScript

Types ship with the package. No @types/... needed:

import type { DefiVault, MarketTrendPoint } from 'stablecoin-yield';

Related

• @barkermoney/skills — official Claude Code / agent skills that use this same data
• GitHub repo — source SKILL.md files

License

MIT