# Constant Sum AMM (Native) This program will create a constant sum AMM. Complete all tasks below - Implement the constant sum AMM. - Test locally with LiteSVM - Deploy locally to `solana-test-validator` and test with Rust script *** Hint *** See [`instructions/lib.rs`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/native/exercise/src/instructions/lib.rs) for token helpers. # Task 1 - Implement [`instructions::init_pool`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/native/exercise/src/instructions/init.rs) - Verify `payer` is signer - Check token decimals are equal - Verify `pool`, `pool_a`, `pool_b` and `mint_pool` accounts are not initialized - Verify provided `pool` PDA matches the one calculated by `lib::get_pool_pda` - Verify provided `mint_pool` PDA matches the one calculated by `lib::get_mint_pool_pda` - Create `pool` PDA - Create `pool_a` associated token account - Create `pool_b` associated token account - Create `mint_pool` PDA - Initialize `mint_pool` - Initialize `Pool` state # Task 2 - Implement [`instructions::add_liquidity`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/native/exercise/src/instructions/add_liquidity.rs) - Verify `payer` is signer - Verify provided `pool` PDA matches the one calculated by `lib::get_pool_pda` - Verify provided `mint_pool` PDA matches the one calculated by `lib::get_mint_pool_pda` - Get `Pool` state - Verify `Pool` state `mint_a` = `mint_a` from `accounts_iter` - Verify `Pool` state `mint_b` = `mint_b` from `accounts_iter` - Get `pool_a` and `pool_b` amounts - Get `mint_pool` supply - Calculate shares to mint - Initialize `payer_liq` (associated token account for `mint_pool` owned by `payer`) if not initialized. - Transfer `mint_a` from payer to `pool_a` - Transfer `mint_b` from payer to `pool_b` - Mint LP tokens to `payer` # Task 3 - Implement [`instructions::remove_liquidity`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/native/exercise/src/instructions/remove_liquidity.rs) - Verify `payer` is signer - Verify provided `pool` PDA matches the one calculated by `lib::get_pool_pda` - Verify provided `mint_pool` PDA matches the one calculated by `lib::get_mint_pool_pda` - Get `Pool` state - Verify `Pool` state `mint_a` = `mint_a` from `accounts_iter` - Verify `Pool` state `mint_b` = `mint_b` from `accounts_iter` - Get `pool_a` and `pool_b` amounts - Get `mint_pool` supply - Calculate amounts of token A and B to withdraw - Check amounts to withdraw are greater or equal to minimum specified by user - Burn LP tokens from payer - Transfer token A from pool to `payer` - Transfer token B from pool to `payer` # Task 4 - Implement [`instructions::swap`](https://github.com/Cyfrin/solana-course/blob/main/apps/amm/native/exercise/src/instructions/swap.rs) - Verify `payer` is signer - Verify provided `pool` PDA matches the one calculated by `lib::get_pool_pda` - Get `Pool` state - Verify `Pool` state `mint_a` = `mint_a` from `accounts_iter` - Verify `Pool` state `mint_b` = `mint_b` from `accounts_iter` - Calculate amount out with fee - Check amount out is >= minimum amount specified by payer - Determine swap direction - Transfer token from `payer` to pool - Transfer token from pool to `payer` # Build ```shell cargo build-sbf ``` # Test ```shell cargo test -- --nocapture ``` # Test with script Run local validator ```shell solana config set -ul solana-test-validator ``` Deploy program ```shell solana program deploy ./target/deploy/amm.so ``` Execute demo script ```shell PROGRAM_ID=your program ID RPC=http://localhost:8899 KEYPAIR=path to key pair cargo run --example demo $KEYPAIR $RPC $PROGRAM_ID ```