A built-in program that loads and executes SBF programs. Solana has multiple loader versions: the deprecated BPF Loader (immutable programs), BPF Loader 2 (deprecated), and the current Upgradeable BPF Loader (BPFLoaderUpgradeable) that supports program upgrades. The loader verifies bytecode, manages deployment, and sets the executable flag.
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A built-in program that loads and executes SBF programs. Solana has multiple loader versions: the deprecated BPF Loader (immutable programs), BPF Loader 2 (deprecated), and the current Upgradeable BPF Loader (BPFLoaderUpgradeable) that supports program upgrades. The loader verifies bytecode, manages deployment, and sets the executable flag.
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BPF Loader (bpf-loader) Category: Programming Model Definition: A built-in program that loads and executes SBF programs. Solana has multiple loader versions: the deprecated BPF Loader (immutable programs), BPF Loader 2 (deprecated), and the current Upgradeable BPF Loader (BPFLoaderUpgradeable) that supports program upgrades. The loader verifies bytecode, manages deployment, and sets the executable flag. Related: Program, Executable Account, Upgradeable BPF Loader
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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).
An account flag indicating the account contains deployed program bytecode. Once marked executable, an account cannot be modified except through the upgrade mechanism. The data field contains the SBF ELF binary (or for upgradeable programs, a pointer to the program data account).
The current BPF Loader (BPFLoaderUpgradeab1e111...) that supports deploying and upgrading programs. It creates three accounts: the program account (thin proxy with executable flag), the program data account (holds the actual ELF bytecode), and records the upgrade authority. Programs can be made immutable by setting the authority to None.
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A built-in program responsible for deploying, loading, and executing on-chain programs by interpreting their binary encoding. Solana has multiple loaders: the original BPF Loader (deprecated, immutable programs), BPF Loader 2 (deprecated), and the current Upgradeable BPF Loader that supports program upgrades and manages the program/program-data account split.
The current BPF Loader (BPFLoaderUpgradeab1e111...) that supports deploying and upgrading programs. It creates three accounts: the program account (thin proxy with executable flag), the program data account (holds the actual ELF bytecode), and records the upgrade authority. Programs can be made immutable by setting the authority to None.
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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).
An account flag indicating the account contains deployed program bytecode. Once marked executable, an account cannot be modified except through the upgrade mechanism. The data field contains the SBF ELF binary (or for upgradeable programs, a pointer to the program data account).
The current BPF Loader (BPFLoaderUpgradeab1e111...) that supports deploying and upgrading programs. It creates three accounts: the program account (thin proxy with executable flag), the program data account (holds the actual ELF bytecode), and records the upgrade authority. Programs can be made immutable by setting the authority to None.
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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.