diff --git a/ethcore/src/executive.rs b/ethcore/src/executive.rs
index c3ef955de..483e3fa31 100644
--- a/ethcore/src/executive.rs
+++ b/ethcore/src/executive.rs
@@ -495,7 +495,7 @@ mod tests {
 	use tests::helpers::*;
 	use trace::trace;
 	use trace::{Trace, Tracer, NoopTracer, ExecutiveTracer};
-	use trace::{VMTrace, VMOperation, VMTracer, NoopVMTracer, ExecutiveVMTracer};
+	use trace::{VMTrace, VMOperation, VMExecutedOperation, MemoryDiff, StorageDiff, VMTracer, NoopVMTracer, ExecutiveVMTracer};
 
 	#[test]
 	fn test_contract_address() {
@@ -681,28 +681,28 @@ mod tests {
 			parent_step: 0,
 			code: vec![124, 96, 16, 128, 96, 12, 96, 0, 57, 96, 0, 243, 0, 96, 0, 53, 84, 21, 96, 9, 87, 0, 91, 96, 32, 53, 96, 0, 53, 85, 96, 0, 82, 96, 29, 96, 3, 96, 23, 240, 96, 0, 85],
 			operations: vec![
-				VMOperation { pc: 1, instruction: 124, gas_cost: x!(3), stack: vecx![] },
-				VMOperation { pc: 31, instruction: 96, gas_cost: x!(3), stack: vecx![U256::from_dec_str("2589892687202724018173567190521546555304938078595079151649957320078677").unwrap()] },
-				VMOperation { pc: 33, instruction: 82, gas_cost: x!(6), stack: vecx![U256::from_dec_str("2589892687202724018173567190521546555304938078595079151649957320078677").unwrap(), 0] },
-				VMOperation { pc: 34, instruction: 96, gas_cost: x!(3), stack: vecx![] },
-				VMOperation { pc: 36, instruction: 96, gas_cost: x!(3), stack: vecx![29] },
-				VMOperation { pc: 38, instruction: 96, gas_cost: x!(3), stack: vecx![29, 3] },
-				VMOperation { pc: 40, instruction: 240, gas_cost: x!(32000), stack: vecx![29, 3, 23] },
-				VMOperation { pc: 41, instruction: 96, gas_cost: x!(3), stack: vecx![U256::from_dec_str("1135198453258042933984631383966629874710669425204").unwrap()] },
-				VMOperation { pc: 43, instruction: 85, gas_cost: x!(20000), stack: vecx![U256::from_dec_str("1135198453258042933984631383966629874710669425204").unwrap(), 0] }
+				VMOperation { pc: 0, instruction: 124, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99997.into(), stack_push: vecx![U256::from_dec_str("2589892687202724018173567190521546555304938078595079151649957320078677").unwrap()], mem_diff: None, store_diff: None }) }, 
+				VMOperation { pc: 30, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99994.into(), stack_push: vecx![0], mem_diff: None, store_diff: None }) }, 
+				VMOperation { pc: 32, instruction: 82, gas_cost: 6.into(), executed: Some(VMExecutedOperation { gas_used: 99988.into(), stack_push: vecx![], mem_diff: Some(MemoryDiff { offset: 0, data: vec![0, 0, 0, 96, 16, 128, 96, 12, 96, 0, 57, 96, 0, 243, 0, 96, 0, 53, 84, 21, 96, 9, 87, 0, 91, 96, 32, 53, 96, 0, 53, 85] }), store_diff: None }) }, 
+				VMOperation { pc: 33, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99985.into(), stack_push: vecx![29], mem_diff: None, store_diff: None }) }, 
+				VMOperation { pc: 35, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99982.into(), stack_push: vecx![3], mem_diff: None, store_diff: None }) }, 
+				VMOperation { pc: 37, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99979.into(), stack_push: vecx![23], mem_diff: None, store_diff: None }) }, 
+				VMOperation { pc: 39, instruction: 240, gas_cost: 32000.into(), executed: Some(VMExecutedOperation { gas_used: 67979.into(), stack_push: vecx![U256::from_dec_str("1135198453258042933984631383966629874710669425204").unwrap()], mem_diff: None, store_diff: None }) }, 
+				VMOperation { pc: 40, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 64752.into(), stack_push: vecx![0], mem_diff: None, store_diff: None }) }, 
+				VMOperation { pc: 42, instruction: 85, gas_cost: 20000.into(), executed: Some(VMExecutedOperation { gas_used: 44752.into(), stack_push: vecx![], mem_diff: None, store_diff: Some(StorageDiff { location: 0.into(), value: U256::from_dec_str("1135198453258042933984631383966629874710669425204").unwrap() }) }) }
 			],
 			subs: vec![
 				VMTrace {
 					parent_step: 7,
 					code: vec![96, 16, 128, 96, 12, 96, 0, 57, 96, 0, 243, 0, 96, 0, 53, 84, 21, 96, 9, 87, 0, 91, 96, 32, 53, 96, 0, 53, 85],
 					operations: vec![
-						VMOperation { pc: 1, instruction: 96, gas_cost: x!(3), stack: vecx![] },
-						VMOperation { pc: 3, instruction: 128, gas_cost: x!(3), stack: vecx![16] },
-						VMOperation { pc: 4, instruction: 96, gas_cost: x!(3), stack: vecx![16, 16] },
-						VMOperation { pc: 6, instruction: 96, gas_cost: x!(3), stack: vecx![16, 16, 12] },
-						VMOperation { pc: 8, instruction: 57, gas_cost: x!(9), stack: vecx![16, 16, 12, 0] },
-						VMOperation { pc: 9, instruction: 96, gas_cost: x!(3), stack: vecx![16] },
-						VMOperation { pc: 11, instruction: 243, gas_cost: x!(0), stack: vecx![16, 0] }
+						VMOperation { pc: 0, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 67976.into(), stack_push: vecx![16], mem_diff: None, store_diff: None }) }, 
+						VMOperation { pc: 2, instruction: 128, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 67973.into(), stack_push: vecx![16, 16], mem_diff: None, store_diff: None }) }, 
+						VMOperation { pc: 3, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 67970.into(), stack_push: vecx![12], mem_diff: None, store_diff: None }) }, 
+						VMOperation { pc: 5, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 67967.into(), stack_push: vecx![0], mem_diff: None, store_diff: None }) }, 
+						VMOperation { pc: 7, instruction: 57, gas_cost: 9.into(), executed: Some(VMExecutedOperation { gas_used: 67958.into(), stack_push: vecx![], mem_diff: Some(MemoryDiff { offset: 0, data: vec![96, 0, 53, 84, 21, 96, 9, 87, 0, 91, 96, 32, 53, 96, 0, 53] }), store_diff: None }) }, 
+						VMOperation { pc: 8, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 67955.into(), stack_push: vecx![0], mem_diff: None, store_diff: None }) }, 
+						VMOperation { pc: 10, instruction: 243, gas_cost: 0.into(), executed: Some(VMExecutedOperation { gas_used: 67955.into(), stack_push: vecx![], mem_diff: None, store_diff: None }) }
 					],
 					subs: vec![]
 				}
@@ -773,13 +773,13 @@ mod tests {
 			parent_step: 0,
 			code: vec![96, 16, 128, 96, 12, 96, 0, 57, 96, 0, 243, 0, 96, 0, 53, 84, 21, 96, 9, 87, 0, 91, 96, 32, 53, 96, 0, 53, 85],
 			operations: vec![
-				VMOperation { pc: 1, instruction: 96, gas_cost: x!(3), stack: vecx![] },
-				VMOperation { pc: 3, instruction: 128, gas_cost: x!(3), stack: vecx![16] },
-				VMOperation { pc: 4, instruction: 96, gas_cost: x!(3), stack: vecx![16, 16] },
-				VMOperation { pc: 6, instruction: 96, gas_cost: x!(3), stack: vecx![16, 16, 12] },
-				VMOperation { pc: 8, instruction: 57, gas_cost: x!(9), stack: vecx![16, 16, 12, 0] },
-				VMOperation { pc: 9, instruction: 96, gas_cost: x!(3), stack: vecx![16] },
-				VMOperation { pc: 11, instruction: 243, gas_cost: x!(0), stack: vecx![16, 0] }
+				VMOperation { pc: 0, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99997.into(), stack_push: vecx![16], mem_diff: None, store_diff: None }) },
+				VMOperation { pc: 2, instruction: 128, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99994.into(), stack_push: vecx![16, 16], mem_diff: None, store_diff: None }) },
+				VMOperation { pc: 3, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99991.into(), stack_push: vecx![12], mem_diff: None, store_diff: None }) },
+				VMOperation { pc: 5, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99988.into(), stack_push: vecx![0], mem_diff: None, store_diff: None }) },
+				VMOperation { pc: 7, instruction: 57, gas_cost: 9.into(), executed: Some(VMExecutedOperation { gas_used: 99979.into(), stack_push: vecx![], mem_diff: Some(MemoryDiff { offset: 0, data: vec![96, 0, 53, 84, 21, 96, 9, 87, 0, 91, 96, 32, 53, 96, 0, 53] }), store_diff: None }) },
+				VMOperation { pc: 8, instruction: 96, gas_cost: 3.into(), executed: Some(VMExecutedOperation { gas_used: 99976.into(), stack_push: vecx![0], mem_diff: None, store_diff: None }) },
+				VMOperation { pc: 10, instruction: 243, gas_cost: 0.into(), executed: Some(VMExecutedOperation { gas_used: 99976.into(), stack_push: vecx![], mem_diff: None, store_diff: None }) }
 			],
 			subs: vec![]
 		};
diff --git a/ethcore/src/trace/mod.rs b/ethcore/src/trace/mod.rs
index e86f483c4..53c062137 100644
--- a/ethcore/src/trace/mod.rs
+++ b/ethcore/src/trace/mod.rs
@@ -31,7 +31,7 @@ pub use self::block::BlockTraces;
 pub use self::config::{Config, Switch};
 pub use self::db::TraceDB;
 pub use self::error::Error;
-pub use types::trace_types::trace::{Trace, VMTrace, VMOperation};
+pub use types::trace_types::trace::{Trace, VMTrace, VMOperation, VMExecutedOperation, MemoryDiff, StorageDiff};
 pub use self::noop_tracer::{NoopTracer, NoopVMTracer};
 pub use self::executive_tracer::{ExecutiveTracer, ExecutiveVMTracer};
 pub use types::trace_types::filter::{Filter, AddressesFilter};
diff --git a/ethcore/src/types/trace_types/trace.rs b/ethcore/src/types/trace_types/trace.rs
index baa1241d3..243acaf64 100644
--- a/ethcore/src/types/trace_types/trace.rs
+++ b/ethcore/src/types/trace_types/trace.rs
@@ -410,9 +410,9 @@ pub struct VMExecutedOperation {
 	pub gas_used: U256,
 	/// The stack item placed, if any.
 	pub stack_push: Vec<U256>,
-	/// If altered, the memory delta, given as (offset, new bytes).
+	/// If altered, the memory delta.
 	pub mem_diff: Option<MemoryDiff>,
-	/// The altered storage value.
+	/// The altered storage value, if any.
 	pub store_diff: Option<StorageDiff>,
 }
 
diff --git a/rpc/src/v1/tests/mocked/eth.rs b/rpc/src/v1/tests/mocked/eth.rs
index 3e9c67f46..b0eae4139 100644
--- a/rpc/src/v1/tests/mocked/eth.rs
+++ b/rpc/src/v1/tests/mocked/eth.rs
@@ -288,7 +288,7 @@ fn rpc_eth_pending_transaction_by_hash() {
 		tester.miner.pending_transactions.lock().unwrap().insert(H256::zero(), tx);
 	}
 
-	let response = r#"{"jsonrpc":"2.0","result":{"blockHash":null,"blockNumber":null,"from":"0x0f65fe9276bc9a24ae7083ae28e2660ef72df99e","gas":"0x5208","gasPrice":"0x01","hash":"0x41df922fd0d4766fcc02e161f8295ec28522f329ae487f14d811e4b64c8d6e31","input":"0x","nonce":"0x00","to":"0x095e7baea6a6c7c4c2dfeb977efac326af552d87","transactionIndex":null,"value":"0x0a"},"id":1}"#;
+	let response = r#"{"jsonrpc":"2.0","result":{"blockHash":null,"blockNumber":null,"creates":null,"from":"0x0f65fe9276bc9a24ae7083ae28e2660ef72df99e","gas":"0x5208","gasPrice":"0x01","hash":"0x41df922fd0d4766fcc02e161f8295ec28522f329ae487f14d811e4b64c8d6e31","input":"0x","nonce":"0x00","to":"0x095e7baea6a6c7c4c2dfeb977efac326af552d87","transactionIndex":null,"value":"0x0a"},"id":1}"#;
 	let request = r#"{
 		"jsonrpc": "2.0",
 		"method": "eth_getTransactionByHash",
diff --git a/rpc/src/v1/types/block.rs b/rpc/src/v1/types/block.rs
index 5810c85e5..b86723357 100644
--- a/rpc/src/v1/types/block.rs
+++ b/rpc/src/v1/types/block.rs
@@ -103,7 +103,7 @@ mod tests {
 	fn test_serialize_block_transactions() {
 		let t = BlockTransactions::Full(vec![Transaction::default()]);
 		let serialized = serde_json::to_string(&t).unwrap();
-		assert_eq!(serialized, r#"[{"hash":"0x0000000000000000000000000000000000000000000000000000000000000000","nonce":"0x00","blockHash":null,"blockNumber":null,"transactionIndex":null,"from":"0x0000000000000000000000000000000000000000","to":null,"value":"0x00","gasPrice":"0x00","gas":"0x00","input":"0x"}]"#);
+		assert_eq!(serialized, r#"[{"hash":"0x0000000000000000000000000000000000000000000000000000000000000000","nonce":"0x00","blockHash":null,"blockNumber":null,"transactionIndex":null,"from":"0x0000000000000000000000000000000000000000","to":null,"value":"0x00","gasPrice":"0x00","gas":"0x00","input":"0x","creates":null}]"#);
 
 		let t = BlockTransactions::Hashes(vec![H256::default()]);
 		let serialized = serde_json::to_string(&t).unwrap();
diff --git a/rpc/src/v1/types/transaction.rs b/rpc/src/v1/types/transaction.rs
index 4193f6d81..e9d4e4cb9 100644
--- a/rpc/src/v1/types/transaction.rs
+++ b/rpc/src/v1/types/transaction.rs
@@ -112,7 +112,7 @@ mod tests {
 		let t = Transaction::default();
 		let serialized = serde_json::to_string(&t).unwrap();
 		// TODO: fix create.
-		assert_eq!(serialized, r#"{"hash":"0x0000000000000000000000000000000000000000000000000000000000000000","nonce":"0x00","blockHash":null,"blockNumber":null,"transactionIndex":null,"from":"0x0000000000000000000000000000000000000000","to":null,"value":"0x00","gasPrice":"0x00","gas":"0x00","input":"0x"}"#);
+		assert_eq!(serialized, r#"{"hash":"0x0000000000000000000000000000000000000000000000000000000000000000","nonce":"0x00","blockHash":null,"blockNumber":null,"transactionIndex":null,"from":"0x0000000000000000000000000000000000000000","to":null,"value":"0x00","gasPrice":"0x00","gas":"0x00","input":"0x","creates":null}"#);
 	}
 }