Deposit

Deposit USDC into the ksUSD vault and receive ksUSD share tokens at the current share price.

New here? Read What is ksUSD? first.

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The instruction

deposit(usdc_amount: u64)

In one atomic transaction:

• Transfers USDC from the user into the vault's USDC ATA

• Mints ksUSD to the user at the current share price

• Updates vault NAV accounting

Account	Mutability	Purpose
vault	mut	Vault PDA (seeds: [b"vault"])
vault_usdc_account	mut	Vault's USDC ATA — receives the deposit
ksusd_mint	mut	ksUSD share mint — vault PDA is authority
user_usdc_account	mut	Depositor's USDC source ATA
user_ksusd_account	mut	Depositor's ksUSD destination ATA
user	signer	Depositor
token_program	—	SPL token program

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Share-price math

share_price_1e9 = (cached_nav_usdc × 1e9) / max(total_shares, 1)
shares_to_mint  = (usdc_amount × 1e9 / share_price_1e9) / 1_000     // ksUSD has 6 decimals

• First deposit into an empty vault mints usdc_amount shares 1:1 at $1.00 (initial share_price_1e9 = 1_000_000_000)

• Every subsequent deposit mints fewer shares as the share price drifts upward with accrued carry

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Guardrails

• Vault must not be paused. Admin can pause via set_pause for emergency response.

• Deposit cap. New deposits revert if cached_nav_usdc + usdc_amount > deposit_cap_usdc (default: $1M cap on launch).

• No zero deposits. usdc_amount > 0 required.

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TypeScript example

import { Program, BN } from "@coral-xyz/anchor";
import { PublicKey } from "@solana/web3.js";
import { TOKEN_PROGRAM_ID, getAssociatedTokenAddressSync } from "@solana/spl-token";

const PROGRAM_ID = new PublicKey("HvsAc157bJ7Pd4uGr7xssHMifGs6RMbPu14ZMsiEABWT");

const [vaultPda] = PublicKey.findProgramAddressSync(
  [Buffer.from("vault")],
  PROGRAM_ID
);

const vault = await program.account.vault.fetch(vaultPda);
const userUsdcAta  = getAssociatedTokenAddressSync(vault.usdcMint,  user.publicKey);
const userKsusdAta = getAssociatedTokenAddressSync(vault.ksusdMint, user.publicKey);
const vaultUsdcAta = getAssociatedTokenAddressSync(vault.usdcMint,  vaultPda, true);

const tx = await program.methods
  .deposit(new BN("100_000_000"))         // 100 USDC (6 decimals)
  .accountsStrict({
    vault: vaultPda,
    vaultUsdcAccount: vaultUsdcAta,
    ksusdMint: vault.ksusdMint,
    userUsdcAccount: userUsdcAta,
    userKsusdAccount: userKsusdAta,
    user: user.publicKey,
    tokenProgram: TOKEN_PROGRAM_ID,
  })
  .rpc();

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Events

DepositEvent is emitted on success:

pub struct DepositEvent {
    pub user: Pubkey,
    pub usdc_amount: u64,
    pub shares_minted: u64,
    pub share_price_1e9: u64,
    pub new_total_shares: u64,
    pub timestamp: i64,
}

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Related

• Withdraw — instant vs. queued paths

• Check position & NAV

• NAV & share pricing

• Errors