Hyperliquid EIP-712 Signing With Turnkey Policies

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One reason Hyperliquid has become such an influential project in 2025 is that it keeps faith with many of the original principles of web3 while delivering the speed and efficiency of a centralized exchange (CEX).

Hyperliquid’s architecture is decentralized, transparent, and fully self-custodial. Hyperliquid’s order book, trades, and liquidations are entirely onchain, and users always control their funds.

Hyperliquid is also permissionless infrastructure. Developers can deploy DeFi protocols, yield vaults, trading bots, or social-trading tools that integrate directly on Hyperliquid without needing licenses, private APIs, or other intermediary approvals.

Hyperliquid also offers HyperEVM, an EVM-compatible environment that supports standard Solidity contracts. Using familiar Ethereum conventions, HyperEVM extends functionality and composability across the broader Web3 ecosystem, rather than being isolated like a centralized exchange. 

Typically, one main difference between a CEX and a DEX has been speed. Hyperliquid changes that speed difference between a CEX and a DEX. Hyperliquid keeps every trade and order onchain while still handling high-frequency workloads at performance levels comparable to any centralized exchange, all without sacrificing transparency or decentralization.

When Hyperliquid is paired with Turnkey’s policy engine, developers can enforce those same principles at scale, users stay in control, and every automation or bot still operates within clear, transparent cryptographic boundaries. 

Turnkey’s infrastructure is also designed for ultra-low latency signing, enabling developers to run policies and authorizations at CEX-level speeds without sacrificing decentralization or security.

This article highlights several Turnkey policies tailored for Hyperliquid EIP-712 signing, showcases real Hyperliquid projects already using Turnkey, and explains how the Turnkey × Hyperliquid stack gives developers powerful, policy-enforced control over automation, execution, and account security.

How Turnkey policies adapt to Hyperliquid workflows

Each Turnkey policy is a simple JSON document that describes approved operations, required quorums, and contextual conditions, forming a cryptographically enforceable rule set.

Developers can define policies that restrict signing to specific contract calls or addresses, whitelist allowed trading pairs, or delegate signing rights to managed services under precise limits.

Using Turnkey’s APIs teams can author, and deploy these policies directly from code. Every authorization is evaluated against verifiable rules before execution, giving builders fine-grained control and auditability at runtime.‍

‍Key Hyperliquid policy features

Turnkey’s policies extend the same flexibility used for Ethereum contracts to onchain Hyperliquid operations. Developers can manage signing authority, restrict contract interactions, and separate automated agent permissions from human approvals.

Enable Hyperliquid EIP-712 signing for orders and agent approvals

Turnkey’s Policy Engine allows you to define precise conditions for signing structured EIP-712 payloads used within the Hyperliquid ecosystem. These Hyperliquid EIP-712 payloads can represent agent approvals, order signing requests, or other typed data actions.

Turnkey’s Policy Engine evaluates each request against your organization’s policies, ensuring that only approved users, credentials, or sub-organizations can authorize a valid signature. Turnkey’s policy evaluation gives developers full visibility into who signed what, and under what rules, before any EIP-712 message reaches the HyperCore or HyperEVM.

Scope signing to verified contracts and transaction types

Turnkey policies can restrict signing to specific smart contract addresses, methods, or EIP-712 domain parameters. For example, you might allow EIP-712 payloads associated with Hyperliquid’s approveAgent schema while denying unrelated or unverified payloads. This tight scoping of Turnkey policies ensures automated agents and trading bots operate only within predefined, auditable boundaries.

Control permissions through users and credentials

Turnkey policies can also limit signing to users or credentials that meet defined conditions, such as having a certain tag, being part of a sub-organization, or using approved authentication methods like passkeys or hardware authenticators. These Turnkey access controls ensure that only trusted users and devices can initiate or approve EIP-712-based operations.

Separate agent wallet approvals from human approval flows

By combining user-level and credential-based rules, organizations can differentiate between automated agent permissions and human approvals. Developers can delegate signing capabilities to service accounts while retaining administrative control for sensitive actions. Separating automation and human approval flows makes it possible to scale Hyperliquid integrations securely across multiple teams, workflows, and automation layers.

See examples on how to implement these Hyperliquid specific policies in the Turnkey docs.

Building and testing Hyperliquid policies

Developers can begin creating Hyperliquid-specific policies using Turnkey’s Quickstart Guide. Using the syntax outlined in the policy language documentation, including the eth.eip_712 namespace for typed data, developers can express precise rules such as allowed message types, domain separators, or HyperEVM contract methods. 

To ensure authorizations, signatures, and verifiable proofs align with intended permissions before promotion to production, Developers should reference the examples using ethers.js or viem in our documentation, depending on their use case. The Turnkey ethers.js and viem examples demonstrate how to construct and sign EIP-712 payloads correctly, providing a reliable baseline for testing Hyperliquid integrations.

Best practices for secure Hyperliquid integrations

Turnkey’s User Best Practices provide a framework for safely deploying and maintaining policy-controlled integrations, especially in high-frequency environments like Hyperliquid. At a minimum, developers should isolate signing keys across sub-organizations to prevent cross-bot exposure and define policies that limit the scope of each actor.

Operational best practices include:

• Rotating root quorums on a scheduled basis to reduce long-term key risk.
  
  
• Using threshold approvals for any policy updates or withdrawal actions.
  
  
• Enforcing read-only audit users to monitor logs and verify policy evaluations without the ability to sign.
  
  
• Capturing all policy decision logs for external verification and compliance reviews.

Each of these operational best practices leverages Turnkey’s hardware-isolated enclaves and verifiable policy evaluation pipeline to maintain end-to-end assurance. The result of these practices is a Hyperliquid integration that is not only performant and composable, but also cryptographically provable, ensuring that every operation can be traced, audited, and trusted.

Examples of Hyperliquid dApps using Turnkey policies

There are a variety of active projects that use Turnkey’s verifiable infrastructure to secure their Hyperliquid integrations. 

Each Hyperliquid project using Turnkey relies on policy-enforced automation, restricting what bots, contracts, or sub-organizations can sign while ensuring transactions remain verifiable through EIP-712 structured data and enclave-backed attestations.

Some of these Hyperliquid projects include:

Together, these Hyperliquid projects demonstrate how Turnkey x Hyperliquid enables fast, automated, and cryptographically enforced DeFi operations, preserving self-custody and transparency at every layer.

Integration Workflow: Turnkey × Hyperliquid

Here is a practical path to implementing Turnkey policies into a Hyperliquid workflow using the Turnkey client SDK. The goal is to authenticate, read or create policies, and enforce EIP-712 order signing with HyperEVM contract scopes.
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By connecting Turnkey’s Policy Engine to Hyperliquid’s onchain infrastructure, developers gain end-to-end control over how trading logic, vaults, and automations are authorized. Each EIP-712 order becomes a transparent, policy-governed action.

Verifiable Hyperliquid operations

The next evolution of Turnkey × Hyperliquid centers on verifiable operations, turning policy compliance itself into cryptographic evidence. Soon Turnkey’s Policy Engine will allow developers to generate signed attestations proving that every Hyperliquid transaction, order submission, or vault interaction originated from an approved policy within a verified enclave. 

See Turnkey’s verifiability roadmap. 

Turnkey’s signed attestations create an auditable record that any exchange, analytics platform, or external auditor can independently verify. For Hyperliquid builders, Turnkey’s signed attestations mean complete traceability across high-frequency operations: every signature can be matched back to its governing policy, and every policy can be traced to a reproducible build and enclave identity.

Turnkey’s verifiable operations model extends Hyperliquid’s own commitment to onchain transparency. By combining Hyperliquid’s fully visible order book with Turnkey’s verifiable signing infrastructure, developers can provide users and partners with cryptographic assurance, not just that trades executed successfully, but that they were executed under explicitly authorized conditions. Turnkey’s verifiable operations model is the future of accountability for automated DeFi systems.

Turnkey x Hyperliquid: Policies for the new transactional era

Turnkey’s Policy Engine lets Hyperliquid developers build at CEX-level speed without compromising web3’s trustless principles. With granular, JSON-defined policies; enclave-secured signing; and full EIP-712 compatibility, builders can automate trading, vault management, and user-facing experiences safely and verifiably.

From gas sponsorship to delegated access and structured-data validation, Turnkey’s Policy Engine makes every workflow transparent and enforceable by design. The result of Turnkey policies on Hyperliquid: faster shipping cycles, fewer operational risks, and stronger guarantees for end-users and auditors alike.

Developers can explore the HyperEVM integration guides and Turnkey’s documentation to start implementing secure, policy-driven dApps on Hyperliquid today, and help shape a verifiable, high-performance DeFi ecosystem for the next generation of builders.

Start building with Turnkey today. 

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