# Specificities This guide covers the essential technical components and considerations for developers building on HyperEVM. For conceptual understanding, see our [HyperEVM Overview](/wiki/architecture/hyperevm.md). ### Important Technical Considerations Before diving into specific features, developers should understand these critical aspects of HyperEVM: * **Partial Atomicity**: Actions from HyperEVM to HyperCore occur in subsequent blocks, your EVM transaction succeeds immediately, but the HyperCore actions it triggers might fail independently. * **Account Initialization**: Smart contracts cannot interact with HyperCore until they have a corresponding HyperCore account. Initialize by sending a small ("dust") amount of any asset to the contract address on HyperCore. * **Balance Tracking**: When transferring assets between environments, a brief "pre-crediting" period exists where balances may not appear in standard queries until the next block. * **Message Origin**: HyperCore sees actions from smart contracts as originating from the contract itself, not the end user. Design your contracts with recovery mechanisms to handle this. *** #### 1. Native Transfers Move spot assets between Hyperliquid’s L1 (“native spot”) and the EVM (“EVM spot”). After **linking** an ERC20 contract to a native asset, you can **deposit** and **withdraw** simply by transferring tokens to the system address (`0x20...`). * **Setup**: Use a `setEvmContract` action to bind the native spot asset with its EVM counterpart. * **Supply**: Ensure the system address holds the full amount of the asset on the “other side.” * **HYPE**: Functions as the **native gas token** on the EVM; special handling is required for deposits/withdrawals. For detailed instructions, see the [Official Docs on Native Transfers](https://hyperliquid.gitbook.io/hyperliquid-docs/for-developers/evm/native-transfers). *** #### 2. Dual-Block Architecture HyperEVM splits throughput into **small blocks** (fast, lower gas limit) and **large blocks** (slower, higher gas limit). Both block types share a single, ever-increasing block number sequence. * **Small Blocks** * Fast confirmations (\~2s per block) * Gas limit: 2M * Ideal for frequent transactions and real-time interactions. * **Large Blocks** * Slower execution (\~1 min per block) * High gas limit: 30M * Designed for complex contract deployments and bulk transactions. Switching between block types can be done via an L1 action (e.g., setting `usingBigBlocks: true`). For a deeper dive, consult the [Official Docs on Dual-Block Architecture](https://hyperliquid.gitbook.io/hyperliquid-docs/for-developers/evm/dual-block-architecture). You can also use this [mainnet frontend tool](https://hyperevm-block-toggle.vercel.app/) to toggle block types directly. *** #### 3. Interacting with the L1 (Read/Write Precompiles) Hyperliquid provides **read** and **write** precompiles to directly access L1 functions without cross-chain complexity. * **Read Precompiles** * **Addresses**: Start at `0x0000000000000000000000000000000000000800`. * **Capabilities**: Query perps positions, spot balances, vault equity, staking delegations, oracle prices, and L1 block numbers. * **Sync**: Always reflects the latest L1 state at EVM block construction. * **Write Precompile** * **Address**: `0x3333333333333333333333333333333333333333`. * **Actions**: Supports placing IOC orders, transferring assets between vaults or perps, staking, and spot sends—directly from the EVM. For code samples and full method details, see the [L1 Integration Docs](https://hyperliquid.gitbook.io/hyperliquid-docs/for-developers/evm/interacting-with-the-l1). *** #### 4. Additional Helpers **4.1 Indexing the HyperEVM** Retrieve raw HyperEVM block data from an **S3 bucket** (`s3://hl-testnet-evm-blocks/`) to build custom services like block explorers or analytics dashboards—no full node required. Files are stored in **MessagePack** format, compressed with **LZ4**, and named by EVM block number. For more information, visit the [Indexing Guide](https://hyperliquid.gitbook.io/hyperliquid-docs/for-developers/evm/raw-hyperevm-block-data). **4.2 Wrapped Hype** A canonical **Wrapped HYPE (WHYPE)** contract is deployed at `0x555...5`. It mirrors the standard wrapped-ETH design—immutable and lightweight—allowing HYPE to function as an **ERC-20** asset within the EVM. Learn more in the [Wrapped HYPE Docs](https://hyperliquid.gitbook.io/hyperliquid-docs/for-developers/evm/wrapped-hype). *** ### Security Patterns - Trust Domain Matching Understanding when to use precompiles versus external oracles is critical for building secure applications on HyperEVM: #### Use Precompiles When: * **Interacting with HyperCore only** - Trading, vault management, staking operations * **Reading HyperCore state** - Positions, balances, internal prices, delegations * **Submitting orders through CoreWriter** - Ensures state consistency with execution engine #### Use External Oracles When: * **External system integration** - Cross-chain bridges, external settlements * **Real-world asset exposure** - BTC/USD prices for stablecoins, cross-exchange arbitrage * **Non-Hyperliquid obligations** - External collateral, multi-chain protocols #### Security Rule If your contract uses **write precompiles** (CoreWriter) to interact with HyperCore, it should trust **read precompiles** for all related price and balance references to avoid state mismatches. #### Key Principles * **Precompiles anchor contracts inside Hyperliquid** - Use for internal system operations * **Oracles anchor contracts to external economic reality** - Use for cross-chain or external obligations * **Trust domain matching** - Ensure every part of your capital flow references the right source of truth *For more details, read* [*Building Safely on Hyperliquid*](https://x.com/emaverick90/status/1926966482765812056)*.* --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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