From 57e4c5d22188310cc21d5b44f1cc7f6cffc58b42 Mon Sep 17 00:00:00 2001
From: 0xfnzero <0xfnzero@users.noreply.github.com>
Date: Fri, 22 May 2026 08:56:20 +0800
Subject: [PATCH] Fix PumpFun V2 buyback fee mutability

---
 Cargo.toml                 |  2 +-
 src/instruction/pumpfun.rs | 22 ++++++++++++++++++++--
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 8223b5f..5fffc22 100755
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "sol-trade-sdk"
-version = "4.0.11"
+version = "4.0.12"
 edition = "2021"
 authors = [
     "William <byteblock6@gmail.com>",
diff --git a/src/instruction/pumpfun.rs b/src/instruction/pumpfun.rs
index adaa3d0..49e4b47 100644
--- a/src/instruction/pumpfun.rs
+++ b/src/instruction/pumpfun.rs
@@ -515,7 +515,7 @@ fn build_buy_v2(params: &SwapParams) -> Result<Vec<Instruction>> {
         AccountMeta::new_readonly(accounts::ASSOCIATED_TOKEN_PROGRAM, false),
         fee_recipient_meta,
         AccountMeta::new(associated_quote_fee_recipient, false),
-        AccountMeta::new_readonly(buyback_fee_recipient, false),
+        AccountMeta::new(buyback_fee_recipient, false),
         AccountMeta::new(associated_quote_buyback_fee_recipient, false),
         AccountMeta::new(bonding_curve_addr, false),
         AccountMeta::new(associated_base_bonding_curve, false),
@@ -705,7 +705,7 @@ fn build_sell_v2(params: &SwapParams) -> Result<Vec<Instruction>> {
         AccountMeta::new_readonly(accounts::ASSOCIATED_TOKEN_PROGRAM, false),
         fee_recipient_meta,
         AccountMeta::new(associated_quote_fee_recipient, false),
-        AccountMeta::new_readonly(buyback_fee_recipient, false),
+        AccountMeta::new(buyback_fee_recipient, false),
         AccountMeta::new(associated_quote_buyback_fee_recipient, false),
         AccountMeta::new(bonding_curve_addr, false),
         AccountMeta::new(associated_base_bonding_curve, false),
@@ -937,6 +937,24 @@ mod tests {
         }
     }
 
+    #[test]
+    fn pumpfun_v2_buyback_fee_recipient_is_writable() {
+        let mint = pump_mint();
+        let mut params = swap_params_for_buy(mint, TOKEN_PROGRAM);
+        params.create_output_mint_ata = false;
+
+        let buy_ix = build_buy_v2(&params).unwrap().pop().unwrap();
+        assert!(global_constants::BUYBACK_FEE_RECIPIENTS.contains(&buy_ix.accounts[8].pubkey));
+        assert!(buy_ix.accounts[8].is_writable);
+
+        params.trade_type = crate::swqos::TradeType::Sell;
+        params.input_mint = mint;
+        params.output_mint = crate::constants::SOL_TOKEN_ACCOUNT;
+        let sell_ix = build_sell_v2(&params).unwrap().pop().unwrap();
+        assert!(global_constants::BUYBACK_FEE_RECIPIENTS.contains(&sell_ix.accounts[8].pubkey));
+        assert!(sell_ix.accounts[8].is_writable);
+    }
+
     #[test]
     fn pumpfun_v1_sell_fixed_output_uses_min_sol_directly() {
         let mint = pump_mint();