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Staking

Introducing the stakefish Multi-Chain Staking API and SDK

stakefish

stakefish

— 4 min read
Introducing the stakefish Multi-Chain Staking API and SDK

The team at stakefish launched two products that make it significantly easier to integrate staking into any platform: the stakefish Multi-Chain Staking API and the stakefish SDK. Together, they give wallets, exchanges, custodians, protocols, and treasury managers a production-ready staking layer across 9+ Proof of Stake networks, without building or maintaining validator infrastructure.

The Problem

Every Proof of Stake network has its own staking mechanics, signing flows, reward distribution models, and unstaking timelines. If you want to offer staking to your users across Ethereum, Solana, Cosmos, and newer networks like Starknet or Monad, you’re looking at separate integrations for each one, each with its own edge cases and operational overhead.

For most teams, this means either limiting staking support to one or two chains, or dedicating significant engineering resources to building and maintaining multi-chain staking infrastructure. Neither option is great. Your users want to stake wherever they hold assets, and your engineering team wants to ship product, not manage validators.

What We Built

The stakefish API and SDK provide a unified interface for the full staking lifecycle: stake, track rewards, unstake, and withdraw, across every supported network. One integration pattern, one set of documentation, one infrastructure partner.

Two Integration Paths

REST API: Direct HTTP endpoints for maximum flexibility. Supports secured API keys for enterprise workflows and public keys for client-facing integrations. Includes an interactive sandbox for testing. View API documentation.

JavaScript/TypeScript SDK: Pre-built libraries for faster integration with built-in error handling and type-safe interfaces. Every SDK follows a consistent four-step workflow: initialize, prepare transaction, sign offline, and broadcast. Additional language support is coming. Browse SDKs.

Supported Networks

Chain

Package

Install

Babylon BABY

@stakefish/sdk-babylon-baby

npm install @stakefish/sdk-babylon-baby

Cardano

@stakefish/sdk-cardano

npm install @stakefish/sdk-cardano

Cosmos Hub

@stakefish/sdk-cosmos

npm install @stakefish/sdk-cosmos

EigenLayer

@stakefish/sdk-eigenlayer

npm install @stakefish/sdk-eigenlayer

Monad

@stakefish/sdk-monad

npm install @stakefish/sdk-monad

Polygon

@stakefish/sdk-polygon

npm install @stakefish/sdk-polygon

Starknet

@stakefish/sdk-starknet

npm install @stakefish/sdk-starknet

SUI

@stakefish/sdk-sui

npm install @stakefish/sdk-sui

zkVerify

@stakefish/sdk-zkverify

npm install @stakefish/sdk-zkverify

Ethereum staking is available through the REST API with two distinct models (see below). All other networks are supported through the SDK.

Ethereum: Two Staking Models

Ethereum is the most complex staking integration, so we’ve built two dedicated paths depending on your use case:

Enterprise Staking is a full-service custodial solution designed for institutions that want stakefish to manage the complete validator lifecycle. It includes comprehensive monthly reporting, block-level reward tracking, a specialized smoothing fee pool for execution-layer rewards, and SOC 2 certification. Enterprise Staking docs.

Client Staking is a non-custodial solution for platforms that want to offer Ethereum staking to their own users while those users maintain self-custody. It includes custom validator distribution, a shared fee pool, and the same SOC 2 certified infrastructure. Client Staking docs.

How Integration Works

Every SDK follows the same four-step pattern, regardless of chain:

1. Initialize the chain-specific client with your configuration (RPC URL, API keys, memo identifier).

2. Prepare an unsigned transaction for the staking operation (delegate, undelegate, withdraw).

3. Sign the transaction offline using your private key. Signing is performed entirely locally. Keys never leave your environment and are never transmitted over the network.

4. Broadcast the signed transaction to the network. All broadcast methods support optional confirmation polling with configurable timeouts.

Example: Staking STRK via the SDK

import { Starknet } from '@stakefish/sdk-starknet';


const starknet = new Starknet({

  rpcUrl: process.env.STARKNET_RPC_URL,

});


const delegatorAddress = '0x049d36...';

const privateKey = process.env.STARKNET_PRIVATE_KEY;


// Stake 100 STRK (amounts in wei: 1 STRK = 10^18)

const unsignedTx = await starknet.stake({

  delegatorAddress,

  amount: '100000000000000000000',

});


// Sign locally

const signedTx = await starknet.sign({ privateKey, unsignedTx });


// Broadcast and wait for confirmation

const result = await starknet.broadcast({ signedTx });

console.log('Tx hash:', result.txHash, 'Status:', result.status);

The Starknet SDK also supports unstaking (with a 21-day unbonding period), withdrawals, reward claiming, and transaction status checks. The same four-step pattern (initialize, prepare, sign, broadcast) applies across all SDK-supported chains. For the full Starknet SDK reference, see the Starknet SDK documentation.

For Ethereum and Solana, stakefish offers dedicated REST APIs with deeper chain-specific functionality. The Ethereum API supports both 0x01 (classic) and 0x02 (compounding) withdrawal credentials, batch validator creation (up to 100 at once), and the full deposit flow. The Solana API handles stake account creation, delegation, merging, splitting, and withdrawals. See the Ethereum Enterprise Staking guide and Solana Staking Flow for complete walkthroughs.

Security

Security is foundational to how the API and SDK are designed:

•  All signing operations happen locally. Private keys and mnemonics are never transmitted over the network.

•  The API supports secured keys for enterprise operations and public keys for client-facing integrations.

•  stakefish infrastructure is SOC 2 certified and has maintained a perfect slashing record: zero events across all networks, ever.

•  The memo parameter used in SDK initialization is assigned by stakefish to identify institutional clients and must be agreed upon before production use.

Who This Is For

Wallets and exchanges that want to offer multi-chain staking to their users without building validator infrastructure.

Protocols and DAOs that need to programmatically manage staking positions across their treasury holdings.

Custodians looking for an institutional-grade staking partner with SOC 2 certification, transparent reporting, and proven uptime.

Treasury managers who want to put idle PoS assets to work across multiple chains through a single integration point.

Proven at Scale

stakefish has been operating validator infrastructure since 2018. We currently manage $1.72 billion in staked assets across 20+ networks, and serve as a trusted infrastructure partner for Lido (founding node operator), EtherFi (core decentralized operator), and OneKey (in-wallet staking provider).

In February 2026, stakefish delivered a 2.99% APR on Ethereum (vs. 2.91% network average), a 99.70% effectiveness rating (vs. 98.32% network average), and a 5.78% APY on Solana (vs. 4.54% network average). Full details are available in our monthly Validator Performance Reports.

Get Started

•  Request API access to start integrating with the stakefish staking infrastructure.

•  Explore the full documentation including API reference, SDK guides, and interactive sandbox.

•  Contact us to discuss your integration needs or request a custom memo identifier for production use.

About stakefish

Founded in 2018 by Ethereum and Bitcoin veterans, stakefish is the leading validator for Proof of Stake blockchains. With support for 15+ networks, we combine institutional‑grade infrastructure with intuitive dashboards, transparent reporting, and a spotless slashing record so individuals and institutions alike can stake confidently while strengthening decentralized networks.

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