Make use_exact_sol_amount optional with true default for PumpFun/PumpSwap

- Change use_exact_sol_amount from bool to Option<bool>
- Default to true (via unwrap_or) for PumpFun and PumpSwap DEXes
- Option is ignored for other DEXes (Raydium, Bonk, Meteora)
- Update all examples to use None (which defaults to true for applicable DEXes)
- Update README documentation

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

examples/address_lookup/src/main.rs

@@ -160,6 +160,7 @@ async fn pumpfun_copy_trade_with_grpc(trade_info: PumpFunTradeEvent) -> AnyResul
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy,
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/bonk_copy_trading/src/main.rs

@@ -175,6 +175,7 @@ async fn bonk_copy_trade_with_grpc(trade_info: BonkTradeEvent) -> AnyResult<()>
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/bonk_sniper_trading/src/main.rs

@@ -143,6 +143,7 @@ async fn bonk_sniper_trade_with_shreds(trade_info: BonkTradeEvent) -> AnyResult<
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/cli_trading/src/main.rs

@@ -634,6 +634,7 @@ async fn handle_buy_pumpfun(
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy,
         simulate: false,
+        use_exact_sol_amount: None,
     };
     match client.buy(buy_params).await {
         Ok((_, signature, _)) => {
@@ -688,6 +689,7 @@ async fn handle_buy_pumpswap(
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy,
         simulate: false,
+        use_exact_sol_amount: None,
     };
     match client.buy(buy_params).await {
         Ok((_, signature, _)) => {
@@ -741,6 +743,7 @@ async fn handle_buy_bonk(
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy,
         simulate: false,
+        use_exact_sol_amount: None,
     };
     match client.buy(buy_params).await {
         Ok((_, signature, _)) => {
@@ -798,6 +801,7 @@ async fn handle_buy_raydium_v4(
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy,
         simulate: false,
+        use_exact_sol_amount: None,
     };
     match client.buy(buy_params).await {
         Ok((_, signature, _)) => {
@@ -855,6 +859,7 @@ async fn handle_buy_raydium_cpmm(
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy,
         simulate: false,
+        use_exact_sol_amount: None,
     };
     match client.buy(buy_params).await {
         Ok((_, signature, _)) => {

examples/meteora_damm_v2_direct_trading/src/main.rs

@@ -43,6 +43,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         fixed_output_token_amount: Some(1),
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/middleware_system/src/main.rs

@@ -102,6 +102,7 @@ async fn test_middleware() -> AnyResult<()> {
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy,
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
     println!("tip: This transaction will not succeed because we're using a test account. You can modify the code to initialize the payer with your own private key");

examples/nonce_cache/src/main.rs

@@ -160,6 +160,7 @@ async fn pumpfun_copy_trade_with_grpc(trade_info: PumpFunTradeEvent) -> AnyResul
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy,
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/pumpfun_copy_trading/src/main.rs

@@ -163,6 +163,7 @@ async fn pumpfun_copy_trade_with_grpc(trade_info: PumpFunTradeEvent) -> AnyResul
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/pumpfun_sniper_trading/src/main.rs

@@ -122,6 +122,7 @@ async fn pumpfun_sniper_trade_with_shreds(trade_info: PumpFunTradeEvent) -> AnyR
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/pumpswap_direct_trading/src/main.rs

@@ -43,6 +43,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/pumpswap_trading/src/main.rs

@@ -220,6 +220,7 @@ async fn pumpswap_trade_with_grpc(mint_pubkey: Pubkey, params: PumpSwapParams) -
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/raydium_amm_v4_trading/src/main.rs

@@ -173,6 +173,7 @@ async fn raydium_amm_v4_copy_trade_with_grpc(trade_info: RaydiumAmmV4SwapEvent)
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/raydium_cpmm_trading/src/main.rs

@@ -158,6 +158,7 @@ async fn raydium_cpmm_copy_trade_with_grpc(trade_info: RaydiumCpmmSwapEvent) ->
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;
 

examples/seed_trading/src/main.rs

@@ -46,6 +46,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         fixed_output_token_amount: None,
         gas_fee_strategy: gas_fee_strategy.clone(),
         simulate: false,
+        use_exact_sol_amount: None,
     };
     client.buy(buy_params).await?;