A technique for accessing on-chain account data directly from the underlying byte buffer without copying it into a new Rust struct, avoiding heap allocation and reducing compute unit usage. In Anchor, zero-copy is enabled via #[account(zero_copy)] on the account struct, which uses repr(C) layout and the AccountLoader type. Ideal for large accounts (>1KB) where Borsh deserialization would be expensive.
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A technique for accessing on-chain account data directly from the underlying byte buffer without copying it into a new Rust struct, avoiding heap allocation and reducing compute unit usage. In Anchor, zero-copy is enabled via #[account(zero_copy)] on the account struct, which uses repr(C) layout and the AccountLoader type. Ideal for large accounts (>1KB) where Borsh deserialization would be expensive.
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Accounts, instructions, PDAs, transactions, and execution flow.
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Zero-Copy Deserialization (zero-copy-deserialization) Category: Programming Model Definition: A technique for accessing on-chain account data directly from the underlying byte buffer without copying it into a new Rust struct, avoiding heap allocation and reducing compute unit usage. In Anchor, zero-copy is enabled via #[account(zero_copy)] on the account struct, which uses repr(C) layout and the AccountLoader type. Ideal for large accounts (>1KB) where Borsh deserialization would be expensive. Related: Account Data, Borsh, AccountLoader (Anchor)
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The byte array stored in an account that holds program-specific state. Data is typically serialized using Borsh and must be explicitly allocated at account creation. The maximum data size is 10MB. Programs are responsible for defining and managing their own data layout, including discriminators for type identification.
Binary Object Representation Serializer for Hashing—the standard serialization format for Solana program data. Borsh produces deterministic, compact binary encodings with a fixed schema. It's used by Anchor for all account and instruction data serialization/deserialization. Borsh supports structs, enums, vectors, and other Rust types.
An Anchor account type that provides zero-copy access to large account data without deserializing the entire account upfront. AccountLoader wraps the raw account data and provides load() and load_mut() methods to access the data as a typed reference. It is used with #[account(zero_copy)] structs and is preferred over Account<T> when accounts exceed ~1KB, as it significantly reduces compute unit consumption.
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The process of converting in-memory data structures to bytes (serialization) and back (deserialization) for on-chain storage. Solana programs primarily use Borsh, though some use bincode or custom formats. Anchor's #[account] macro auto-derives Borsh serialization. Incorrect deserialization (e.g., missing length checks) is a common vulnerability class.
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The byte array stored in an account that holds program-specific state. Data is typically serialized using Borsh and must be explicitly allocated at account creation. The maximum data size is 10MB. Programs are responsible for defining and managing their own data layout, including discriminators for type identification.
Binary Object Representation Serializer for Hashing—the standard serialization format for Solana program data. Borsh produces deterministic, compact binary encodings with a fixed schema. It's used by Anchor for all account and instruction data serialization/deserialization. Borsh supports structs, enums, vectors, and other Rust types.
An Anchor account type that provides zero-copy access to large account data without deserializing the entire account upfront. AccountLoader wraps the raw account data and provides load() and load_mut() methods to access the data as a typed reference. It is used with #[account(zero_copy)] structs and is preferred over Account<T> when accounts exceed ~1KB, as it significantly reduces compute unit consumption.
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The fundamental data storage unit on Solana. Every piece of state is stored in an account identified by a 32-byte public key. Accounts hold a lamport balance, an owner program, a data byte array (up to 10MB), and an executable flag. Only the owning program can modify an account's data, but anyone can credit lamports to it.
Executable code deployed on-chain, equivalent to a smart contract on other blockchains. Programs are stateless—they store no data themselves but read/write data in separate accounts they own. Programs are compiled to SBF bytecode and loaded via the BPF Loader. Every program has a unique Program ID (its account's public key).
A single operation within a transaction that invokes a program. An instruction specifies: (1) the program ID to call, (2) an array of account metas (pubkey, is_signer, is_writable), and (3) an opaque data byte array. Programs decode the instruction data to determine which operation to perform.
An atomic unit of execution containing one or more instructions, a recent blockhash, and one or more signatures. All instructions in a transaction execute sequentially and atomically—if any instruction fails, the entire transaction reverts. Transactions have a 1,232-byte size limit (matching IPv6 MTU) and a default 200,000 CU budget.