Replicating Anchor's remaining_accounts in a native Solana program: slice the accounts array past your expected count

A native (non-Anchor) program appears to have no way to accept a variable-length list of accounts, because the entrypoint hands you a fixed &[AccountInfo] and there is no macro-provided remaining_accounts field.

The underlying fact is that nothing about the runtime limits the accounts array to the number your program expects. A client may pass 12 accounts to an instruction that only reads 10; the extra ones are still delivered, in order, at the tail of the slice. Anchor's Context::remaining_accounts is exactly that tail — the #[derive(Accounts)] struct claims indices 0..N and Anchor exposes &accounts[N..] under a different name, with no deserialization or validation applied.

In a native program you do the same slice by hand:

let remaining_accounts = &accounts[10..];   // 10 = accounts your ix always needs

let account_metas: Vec<AccountMeta> = remaining_accounts
    .iter()
    .map(|acc| AccountMeta::new(*acc.key, false))
    .collect();

let ix = Instruction::new_with_bytes(program_id, &data, account_metas);

Two cautions this makes easy to miss. Slice with a checked pattern (accounts.get(10..).unwrap_or(&[])) so a client that sends the minimum set does not panic on an out-of-range index. And these accounts carry zero validation: nothing has checked their owner, signer status, or writability, so any invariant you need must be asserted explicitly before you forward them into a CPI.

Source: adapted from a Stack Exchange answer by Joey Meere (question by Joey Meere), https://solana.stackexchange.com/questions/14577/replicate-anchor-remaining-accounts-in-native — CC BY-SA 4.0