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 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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Upgradeable BPF Loader (upgradeable-loader) Category: Programming Model Definition: 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. Aliases: BPFLoaderUpgradeable Related: BPF Loader, Program Data Account, Upgrade Authority
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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.
The account that stores the actual SBF ELF bytecode for an upgradeable program. It is separate from the program's main account (which just points to the program data). This separation allows the bytecode to be swapped during upgrades while the program ID stays the same. The program data account also stores the upgrade authority pubkey.
The pubkey authorized to upgrade a program's bytecode via the Upgradeable BPF Loader. Only the upgrade authority can deploy new bytecode to the program data account. Setting the upgrade authority to None makes the program immutable. Multisig (e.g., Squads) is commonly used to manage upgrade authority for production programs.
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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.
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.
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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.
The account that stores the actual SBF ELF bytecode for an upgradeable program. It is separate from the program's main account (which just points to the program data). This separation allows the bytecode to be swapped during upgrades while the program ID stays the same. The program data account also stores the upgrade authority pubkey.
The pubkey authorized to upgrade a program's bytecode via the Upgradeable BPF Loader. Only the upgrade authority can deploy new bytecode to the program data account. Setting the upgrade authority to None makes the program immutable. Multisig (e.g., Squads) is commonly used to manage upgrade authority for production programs.
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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.