chore: LightProgramInterface program rent sponsor

forester/tests/test_compressible_pda.rs

@@ -48,8 +48,10 @@ const CSDK_TEST_PROGRAM_ID: &str = "FAMipfVEhN4hjCLpKCvjDXXfzLsoVTqQccXzePz1L1ah
 // This needs to match the discriminator from csdk_anchor_full_derived_test::state::d1_field_types::single_pubkey::SinglePubkeyRecord
 const SINGLE_PUBKEY_RECORD_DISCRIMINATOR: [u8; 8] = csdk_anchor_full_derived_test::state::d1_field_types::single_pubkey::SinglePubkeyRecord::LIGHT_DISCRIMINATOR;
 
-// Rent sponsor pubkey used in tests
-const RENT_SPONSOR: Pubkey = solana_sdk::pubkey!("CLEuMG7pzJX9xAuKCFzBP154uiG1GaNo4Fq7x6KAcAfG");
+/// Get the program's derived rent sponsor PDA
+fn program_rent_sponsor() -> Pubkey {
+    csdk_anchor_full_derived_test::light_rent_sponsor()
+}
 
 /// Context returned from forester registration
 struct ForesterContext {
@@ -97,8 +99,8 @@ async fn register_forester<R: Rpc>(
         .config;
 
     // Use airdrop for forester
-    println!("Funding forester {} with 10 SOL", forester_pubkey);
-    rpc.airdrop_lamports(&forester_pubkey, 10_000_000_000)
+    println!("Funding forester {} with 2 SOL", forester_pubkey);
+    rpc.airdrop_lamports(&forester_pubkey, 2_000_000_000)
         .await?;
     sleep(Duration::from_millis(500)).await;
 
@@ -280,30 +282,27 @@ async fn test_compressible_pda_bootstrap() {
     let authority = Keypair::try_from(PAYER_KEYPAIR.as_ref()).expect("Invalid PAYER_KEYPAIR");
 
     // Fund the authority account
-    rpc.airdrop_lamports(&authority.pubkey(), 10_000_000_000)
+    rpc.airdrop_lamports(&authority.pubkey(), 2_000_000_000)
         .await
         .expect("Failed to airdrop to authority");
 
-    // Fund rent sponsor
-    rpc.airdrop_lamports(&RENT_SPONSOR, 10_000_000_000)
-        .await
-        .expect("Failed to fund rent sponsor");
-
-    // Initialize compression config
-    let (init_config_ix, config_pda) = InitializeRentFreeConfig::new(
+    // Initialize compression config (includes rent sponsor funding)
+    let rent_sponsor = program_rent_sponsor();
+    let (init_config_ixs, config_pda) = InitializeRentFreeConfig::new(
         &program_id,
         &authority.pubkey(),
         &Pubkey::find_program_address(
             &[program_id.as_ref()],
             &solana_sdk::pubkey!("BPFLoaderUpgradeab1e11111111111111111111111"),
         )
         .0,
-        RENT_SPONSOR,
+        rent_sponsor,
         authority.pubkey(),
+        500_000_000, // 0.5 SOL for rent sponsor
     )
     .build();
 
-    rpc.create_and_send_transaction(&[init_config_ix], &authority.pubkey(), &[&authority])
+    rpc.create_and_send_transaction(&init_config_ixs, &authority.pubkey(), &[&authority])
         .await
         .expect("Initialize config should succeed");
 
@@ -470,30 +469,27 @@ async fn test_compressible_pda_compression() {
     let authority = Keypair::try_from(PAYER_KEYPAIR.as_ref()).expect("Invalid PAYER_KEYPAIR");
 
     // Fund the authority account
-    rpc.airdrop_lamports(&authority.pubkey(), 10_000_000_000)
+    rpc.airdrop_lamports(&authority.pubkey(), 2_000_000_000)
         .await
         .expect("Failed to airdrop to authority");
 
-    // Fund rent sponsor
-    rpc.airdrop_lamports(&RENT_SPONSOR, 10_000_000_000)
-        .await
-        .expect("Failed to fund rent sponsor");
-
-    // Initialize compression config
-    let (init_config_ix, config_pda) = InitializeRentFreeConfig::new(
+    // Initialize compression config (includes rent sponsor funding)
+    let rent_sponsor = program_rent_sponsor();
+    let (init_config_ixs, config_pda) = InitializeRentFreeConfig::new(
         &program_id,
         &authority.pubkey(),
         &Pubkey::find_program_address(
             &[program_id.as_ref()],
             &solana_sdk::pubkey!("BPFLoaderUpgradeab1e11111111111111111111111"),
         )
         .0,
-        RENT_SPONSOR,
+        rent_sponsor,
         authority.pubkey(),
+        500_000_000, // 0.5 SOL for rent sponsor
     )
     .build();
 
-    rpc.create_and_send_transaction(&[init_config_ix], &authority.pubkey(), &[&authority])
+    rpc.create_and_send_transaction(&init_config_ixs, &authority.pubkey(), &[&authority])
         .await
         .expect("Initialize config should succeed");
 
@@ -703,33 +699,32 @@ async fn test_compressible_pda_subscription() {
     let authority = Keypair::try_from(&PAYER_KEYPAIR[..]).unwrap();
 
     // Fund accounts
-    rpc.airdrop_lamports(&authority.pubkey(), 10_000_000_000)
+    rpc.airdrop_lamports(&authority.pubkey(), 2_000_000_000)
         .await
         .expect("Failed to airdrop to authority");
-    rpc.airdrop_lamports(&RENT_SPONSOR, 10_000_000_000)
-        .await
-        .expect("Failed to fund rent sponsor");
 
     // Wait for indexer
     wait_for_indexer(&rpc)
         .await
         .expect("Failed to wait for indexer");
 
-    // Initialize compression config
-    let (init_config_ix, config_pda) = InitializeRentFreeConfig::new(
+    // Initialize compression config (includes rent sponsor funding)
+    let rent_sponsor = program_rent_sponsor();
+    let (init_config_ixs, config_pda) = InitializeRentFreeConfig::new(
         &program_id,
         &authority.pubkey(),
         &Pubkey::find_program_address(
             &[program_id.as_ref()],
             &solana_sdk::pubkey!("BPFLoaderUpgradeab1e11111111111111111111111"),
         )
         .0,
-        RENT_SPONSOR,
+        rent_sponsor,
         authority.pubkey(),
+        500_000_000, // 0.5 SOL for rent sponsor
     )
     .build();
 
-    rpc.create_and_send_transaction(&[init_config_ix], &authority.pubkey(), &[&authority])
+    rpc.create_and_send_transaction(&init_config_ixs, &authority.pubkey(), &[&authority])
         .await
         .expect("Initialize config should succeed");
 

sdk-libs/client/Cargo.toml

@@ -37,6 +37,7 @@ solana-address-lookup-table-interface = { version = "2.2.1", features = [
     "bincode",
 ] }
 solana-message = { workspace = true }
+solana-system-interface = { workspace = true }
 spl-token-2022-interface = { workspace = true }
 spl-pod = { workspace = true }
 

sdk-libs/client/src/interface/initialize_config.rs

@@ -7,6 +7,7 @@ use borsh::{BorshDeserialize as AnchorDeserialize, BorshSerialize as AnchorSeria
 use light_sdk::interface::config::LightConfig;
 use solana_instruction::{AccountMeta, Instruction};
 use solana_pubkey::Pubkey;
+use solana_system_interface::instruction as system_instruction;
 
 /// Default address tree v2 pubkey.
 pub const ADDRESS_TREE_V2: Pubkey =
@@ -20,18 +21,22 @@ pub const DEFAULT_INIT_WRITE_TOP_UP: u32 = 5_000;
 pub struct InitializeCompressionConfigAnchorData {
     pub write_top_up: u32,
     pub rent_sponsor: Pubkey,
+    pub rent_sponsor_bump: u8,
     pub compression_authority: Pubkey,
     pub rent_config: light_compressible::rent::RentConfig,
     pub address_space: Vec<Pubkey>,
 }
 
 /// Builder for `initialize_compression_config` instruction with sensible defaults.
+///
+/// Automatically includes a transfer instruction to fund the rent sponsor PDA.
 pub struct InitializeRentFreeConfig {
     program_id: Pubkey,
     fee_payer: Pubkey,
     program_data_pda: Pubkey,
     authority: Option<Pubkey>,
     rent_sponsor: Pubkey,
+    rent_sponsor_funding: u64,
     compression_authority: Pubkey,
     rent_config: light_compressible::rent::RentConfig,
     write_top_up: u32,
@@ -40,19 +45,26 @@ pub struct InitializeRentFreeConfig {
 }
 
 impl InitializeRentFreeConfig {
+    /// Creates a new builder for initializing rent-free config.
+    ///
+    /// # Arguments
+    /// * `rent_sponsor_funding` - Lamports to transfer to the rent sponsor PDA.
+    ///   This funds the PDA that will pay rent for compressed accounts.
     pub fn new(
         program_id: &Pubkey,
         fee_payer: &Pubkey,
         program_data_pda: &Pubkey,
         rent_sponsor: Pubkey,
         compression_authority: Pubkey,
+        rent_sponsor_funding: u64,
     ) -> Self {
         Self {
             program_id: *program_id,
             fee_payer: *fee_payer,
             program_data_pda: *program_data_pda,
             authority: None,
             rent_sponsor,
+            rent_sponsor_funding,
             compression_authority,
             rent_config: light_compressible::rent::RentConfig::default(),
             write_top_up: DEFAULT_INIT_WRITE_TOP_UP,
@@ -86,10 +98,34 @@ impl InitializeRentFreeConfig {
         self
     }
 
-    pub fn build(self) -> (Instruction, Pubkey) {
+    /// Builds the instructions to initialize rent-free config.
+    ///
+    /// Returns a vector containing:
+    /// 1. Transfer instruction to fund the rent sponsor PDA
+    /// 2. Initialize compression config instruction
+    ///
+    /// Both instructions should be sent in a single atomic transaction.
+    pub fn build(self) -> (Vec<Instruction>, Pubkey) {
         let authority = self.authority.unwrap_or(self.fee_payer);
         let (config_pda, _) = LightConfig::derive_pda(&self.program_id, self.config_bump);
 
+        // Derive rent sponsor bump (version 1, hardcoded)
+        let (derived_rent_sponsor, rent_sponsor_bump) =
+            Pubkey::find_program_address(&[b"rent_sponsor", &1u16.to_le_bytes()], &self.program_id);
+        assert_eq!(
+            derived_rent_sponsor, self.rent_sponsor,
+            "Rent sponsor PDA mismatch: derived {:?} != provided {:?}",
+            derived_rent_sponsor, self.rent_sponsor
+        );
+
+        // 1. Transfer to fund rent sponsor PDA
+        let transfer_ix = system_instruction::transfer(
+            &self.fee_payer,
+            &self.rent_sponsor,
+            self.rent_sponsor_funding,
+        );
+
+        // 2. Initialize compression config
         let accounts = vec![
             AccountMeta::new(self.fee_payer, true), // payer
             AccountMeta::new(config_pda, false),    // config
@@ -104,6 +140,7 @@ impl InitializeRentFreeConfig {
         let instruction_data = InitializeCompressionConfigAnchorData {
             write_top_up: self.write_top_up,
             rent_sponsor: self.rent_sponsor,
+            rent_sponsor_bump,
             compression_authority: self.compression_authority,
             rent_config: self.rent_config,
             address_space: self.address_space,
@@ -121,12 +158,12 @@ impl InitializeRentFreeConfig {
         data.extend_from_slice(&DISCRIMINATOR);
         data.extend_from_slice(&serialized_data);
 
-        let instruction = Instruction {
+        let init_config_ix = Instruction {
             program_id: self.program_id,
             accounts,
             data,
         };
 
-        (instruction, config_pda)
+        (vec![transfer_ix, init_config_ix], config_pda)
     }
 }

sdk-libs/client/src/interface/light_program_interface.rs

@@ -229,6 +229,16 @@ pub trait LightProgramInterface: Sized {
     #[must_use]
     fn program_id(&self) -> Pubkey;
 
+    /// Returns the program's LightConfig PDA.
+    /// Used for PDA decompression instructions.
+    #[must_use]
+    fn light_config_pda(&self) -> Pubkey;
+
+    /// Returns the program's rent sponsor PDA for cPDAs (version 1).
+    /// Derived via `derive_light_rent_sponsors!` macro.
+    #[must_use]
+    fn light_rent_sponsor_pda(&self) -> Pubkey;
+
     /// Construct SDK from root account(s).
     fn from_keyed_accounts(accounts: &[AccountInterface]) -> Result<Self, Self::Error>;
 

sdk-libs/compressed-token-sdk/src/compressed_token/v2/create_compressed_mint/instruction.rs

@@ -70,12 +70,12 @@ pub fn create_compressed_mint_cpi(
         instruction_data = instruction_data.with_cpi_context(ctx);
     }
 
-    let meta_config = if cpi_context_pubkey.is_some() {
+    let meta_config = if let Some(ctx_pubkey) = cpi_context_pubkey {
         MintActionMetaConfig::new_cpi_context(
             &instruction_data,
             input.payer,
             input.mint_authority,
-            cpi_context_pubkey.unwrap(),
+            ctx_pubkey,
         )?
     } else {
         MintActionMetaConfig::new_create_mint(

sdk-libs/compressed-token-sdk/src/compressed_token/v2/mint_to_compressed/instruction.rs

@@ -70,13 +70,8 @@ pub fn create_mint_to_compressed_instruction(
         instruction_data = instruction_data.with_cpi_context(ctx);
     }
 
-    let meta_config = if cpi_context_pubkey.is_some() {
-        MintActionMetaConfig::new_cpi_context(
-            &instruction_data,
-            payer,
-            mint_authority,
-            cpi_context_pubkey.unwrap(),
-        )?
+    let meta_config = if let Some(ctx_pubkey) = cpi_context_pubkey {
+        MintActionMetaConfig::new_cpi_context(&instruction_data, payer, mint_authority, ctx_pubkey)?
     } else {
         MintActionMetaConfig::new(
             payer,

sdk-libs/macros/src/lib.rs

@@ -339,34 +339,22 @@ pub fn light_account_derive(input: TokenStream) -> TokenStream {
     into_token_stream(light_pdas::account::light_compressible::derive_light_account(input))
 }
 
-/// Derives a Rent Sponsor PDA for a program at compile time.
+/// Derives the Rent Sponsor PDA at compile time (version 1, hardcoded).
 ///
-/// Seeds: ["rent_sponsor", <u16 version little-endian>]
-///
-/// ## Example
-///
-/// ```ignore
-/// use light_sdk_macros::derive_light_rent_sponsor_pda;
-///
-/// pub const RENT_SPONSOR_DATA: ([u8; 32], u8) =
-///     derive_light_rent_sponsor_pda!("8Ld9pGkCNfU6A7KdKe1YrTNYJWKMCFqVHqmUvjNmER7B", 1);
-/// ```
-#[proc_macro]
-pub fn derive_light_rent_sponsor_pda(input: TokenStream) -> TokenStream {
-    rent_sponsor::derive_light_rent_sponsor_pda(input)
-}
-
-/// Derives a complete Rent Sponsor configuration for a program at compile time.
-///
-/// Returns ::light_sdk_types::RentSponsor { program_id, rent_sponsor, bump, version }.
+/// Returns a `RentSponsor` struct with the PDA address and bump.
 ///
 /// ## Example
 ///
 /// ```ignore
 /// use light_sdk_macros::derive_light_rent_sponsor;
 ///
-/// pub const RENT_SPONSOR: ::light_sdk_types::RentSponsor =
-///     derive_light_rent_sponsor!("8Ld9pGkCNfU6A7KdKe1YrTNYJWKMCFqVHqmUvjNmER7B", 1);
+/// pub const RENT_SPONSOR: ::light_sdk::sdk_types::RentSponsor =
+///     derive_light_rent_sponsor!("8Ld9pGkCNfU6A7KdKe1YrTNYJWKMCFqVHqmUvjNmER7B");
+///
+/// // Access the pubkey
+/// let pubkey = Pubkey::from(RENT_SPONSOR.rent_sponsor);
+/// // Access the bump for signing
+/// let bump = RENT_SPONSOR.bump;
 /// ```
 #[proc_macro]
 pub fn derive_light_rent_sponsor(input: TokenStream) -> TokenStream {

sdk-libs/macros/src/light_pdas/account/decompress_context.rs

@@ -81,6 +81,7 @@ pub fn generate_decompress_context_trait_impl(
                     #seed_params_update
                     light_sdk::interface::handle_packed_pda_variant::<#inner_type, #packed_inner_type, _, _>(
                         &*self.rent_sponsor,
+                        rent_sponsor_seeds,
                         cpi_accounts,
                         address_space,
                         &solana_accounts[i],
@@ -157,6 +158,7 @@ pub fn generate_decompress_context_trait_impl(
                 compressed_accounts: Vec<Self::CompressedData>,
                 solana_accounts: &[solana_account_info::AccountInfo<#lifetime>],
                 seed_params: std::option::Option<&Self::SeedParams>,
+                rent_sponsor_seeds: &[&[u8]],
             ) -> std::result::Result<(
                 Vec<::light_sdk::compressed_account::CompressedAccountInfo>,
                 Vec<(Self::PackedTokenData, Self::CompressedMeta)>,