Hyperliquid L1 Read Precompiles: Complete Guide
Hyperliquid L1 read precompiles let HyperEVM contracts query selected HyperCore state directly at protocol-defined addresses, avoiding a separate offchain oracle for supported data.
L1 read precompiles are the native read bridge from HyperEVM into HyperCore. A contract calls protocol-defined addresses beginning in the 0x...0800 range and receives data such as perpetual positions, spot balances, vault equity, staking delegations, oracle prices, or the L1 block number. The returned values correspond to the latest HyperCore state available when the EVM block is constructed.
Why a precompile instead of a normal contract
A normal Solidity contract can only read state exposed inside the EVM unless an oracle or message-passing system imports outside information. HyperCore state is not ordinary Solidity storage. Precompiles give the EVM a protocol-native function for selected reads.
This is valuable because an application can reference native financial state without trusting an application-operated indexing server as the final source.
Addresses, inputs, and scaling
The official L1Read.sol interface documents each precompile and its ABI. Returned numerical values often use fixed-point representations whose scaling depends on the asset and its szDecimals. Developers must apply the documented conversion rather than assuming 18-decimal EVM conventions.
A wrong scale factor can be more dangerous than a reverted call because it produces plausible but incorrect prices or sizes.
Failure and gas behavior
Invalid inputs can cause a precompile call frame to consume the gas provided to it. Current documentation specifies a gas-cost formula based on input and output length. Contracts should therefore validate asset identifiers and addresses before making reads where possible.
A protocol read is still part of EVM execution and should be included in gas estimates.
State timing
The value corresponds to HyperCore state when the EVM block is built. It is not a promise that every offchain API response observed a millisecond later will have the same timestamp.
Applications that combine precompile state with external feeds should define which timestamp and source governs each decision.
Design patterns
Precompiles are useful for collateral checks, position-aware vault logic, native-price references, staking-aware applications, and protocols that need to inspect HyperCore balances before taking action.
Keep business logic separate from decoding. A small audited library that wraps the protocol interface is safer than duplicating byte-level conversions throughout a codebase.