The broader developer workflow of dry-running a Solana transaction before broadcast to inspect logs, catch runtime failures, estimate compute usage, and verify account assumptions. Transaction simulation can happen through the simulateTransaction RPC method, preflight checks inside sendTransaction, or specialized bundle and bot pipelines that repeatedly simulate against fresh state before deciding to submit.
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The broader developer workflow of dry-running a Solana transaction before broadcast to inspect logs, catch runtime failures, estimate compute usage, and verify account assumptions. Transaction simulation can happen through the simulateTransaction RPC method, preflight checks inside sendTransaction, or specialized bundle and bot pipelines that repeatedly simulate against fresh state before deciding to submit.
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Accounts, instructions, PDAs, transactions, and execution flow.
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Transaction Simulation (transaction-simulation) Category: Programming Model Definition: The broader developer workflow of dry-running a Solana transaction before broadcast to inspect logs, catch runtime failures, estimate compute usage, and verify account assumptions. Transaction simulation can happen through the simulateTransaction RPC method, preflight checks inside sendTransaction, or specialized bundle and bot pipelines that repeatedly simulate against fresh state before deciding to submit. Related: Simulate Transaction, Preflight Check, Bundle Simulation
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The simulateTransaction RPC method that dry-runs a transaction against a specified bank state without submitting it to the network or consuming fees. Simulation returns the execution result including logs, compute units consumed, return data, and any error. Developers use simulation to estimate CU usage, debug program errors, and verify transaction correctness before sending. Simulation does not require valid signatures.
An RPC-level simulation that runs a transaction against the current bank state before forwarding it to the leader for actual execution. Preflight checks catch common errors (insufficient funds, invalid blockhash, CU overrun, program errors) before the transaction is submitted to the cluster. Preflight can be skipped via the skipPreflight option in sendTransaction, which is sometimes used when the simulation state lags behind the leader's state.
The process of executing a Jito bundle against the current chain state in a sandboxed environment to verify that all transactions in the bundle succeed and produce the expected outcome before committing real tips and submitting to the Block Engine. Simulation catches issues like stale state, insufficient balances, or failed arbitrage conditions, preventing searchers from paying tips for bundles that would fail on-chain. Jito provides simulateBundle API endpoints for this purpose.
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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.
The first signature in a transaction, which uniquely identifies it on the network. Since each transaction has a unique combination of signers and a recent blockhash, the first signer's Ed25519 signature over the transaction message serves as a globally unique identifier. Transaction IDs are displayed as Base58-encoded 64-byte strings and used for lookups via getTransaction and getSignatureStatuses.
The limited lifespan of a Solana transaction determined by its referenced blockhash. A transaction's blockhash must correspond to a block within the last 150 slots (~60-90 seconds) or the transaction is rejected as expired. This mechanism prevents replay attacks and bounds the time validators must track transaction deduplication. Durable nonces bypass mortality for use cases requiring long-lived transactions.
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The simulateTransaction RPC method that dry-runs a transaction against a specified bank state without submitting it to the network or consuming fees. Simulation returns the execution result including logs, compute units consumed, return data, and any error. Developers use simulation to estimate CU usage, debug program errors, and verify transaction correctness before sending. Simulation does not require valid signatures.
An RPC-level simulation that runs a transaction against the current bank state before forwarding it to the leader for actual execution. Preflight checks catch common errors (insufficient funds, invalid blockhash, CU overrun, program errors) before the transaction is submitted to the cluster. Preflight can be skipped via the skipPreflight option in sendTransaction, which is sometimes used when the simulation state lags behind the leader's state.
The process of executing a Jito bundle against the current chain state in a sandboxed environment to verify that all transactions in the bundle succeed and produce the expected outcome before committing real tips and submitting to the Block Engine. Simulation catches issues like stale state, insufficient balances, or failed arbitrage conditions, preventing searchers from paying tips for bundles that would fail on-chain. Jito provides simulateBundle API endpoints for this purpose.
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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.