diff --git a/src/engine.rs b/src/engine.rs
index 59888d12a..61abc9bb3 100644
--- a/src/engine.rs
+++ b/src/engine.rs
@@ -2,6 +2,7 @@ use common::*;
 use block::Block;
 use spec::Spec;
 use evm::Schedule;
+use evm::Factory;
 
 /// A consensus mechanism for the chain. Generally either proof-of-work or proof-of-stake-based.
 /// Provides hooks into each of the major parts of block import.
@@ -22,6 +23,9 @@ pub trait Engine : Sync + Send {
 	/// Get the general parameters of the chain.
 	fn spec(&self) -> &Spec;
 
+	/// Get current EVM factory
+	fn vm_factory(&self) -> &Factory;
+
 	/// Get the EVM schedule for the given `env_info`.
 	fn schedule(&self, env_info: &EnvInfo) -> Schedule;
 
diff --git a/src/ethereum/ethash.rs b/src/ethereum/ethash.rs
index f2f5eeafd..8a0450e72 100644
--- a/src/ethereum/ethash.rs
+++ b/src/ethereum/ethash.rs
@@ -3,16 +3,22 @@ use block::*;
 use spec::*;
 use engine::*;
 use evm::Schedule;
+use evm::Factory;
 
 /// Engine using Ethash proof-of-work consensus algorithm, suitable for Ethereum
 /// mainnet chains in the Olympic, Frontier and Homestead eras.
 pub struct Ethash {
 	spec: Spec,
+	factory: Factory
 }
 
 impl Ethash {
 	pub fn new_boxed(spec: Spec) -> Box<Engine> {
-		Box::new(Ethash{spec: spec})
+		Box::new(Ethash{
+			spec: spec,
+			// TODO [todr] should this return any specific factory?
+			factory: Factory::default()
+		})
 	}
 }
 
@@ -27,7 +33,11 @@ impl Engine for Ethash {
 	/// Additional engine-specific information for the user/developer concerning `header`.
 	fn extra_info(&self, _header: &Header) -> HashMap<String, String> { HashMap::new() }
 	fn spec(&self) -> &Spec { &self.spec }
+
 	fn schedule(&self, _env_info: &EnvInfo) -> Schedule { Schedule::new_frontier() }
+	fn vm_factory(&self) -> &Factory {
+		&self.factory
+	}
 
 	/// Apply the block reward on finalisation of the block.
 	/// This assumes that all uncles are valid uncles (i.e. of at least one generation before the current).
diff --git a/src/evm/factory.rs b/src/evm/factory.rs
index 39019cd8d..25a41afd2 100644
--- a/src/evm/factory.rs
+++ b/src/evm/factory.rs
@@ -1,25 +1,99 @@
 //! Evm factory.
-
+use std::fmt;
 use evm::Evm;
 
+#[derive(Clone)]
+pub enum VMType {
+	Jit,
+	Interpreter
+}
+impl fmt::Display for VMType {
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+		write!(f, "{}", match *self {
+			VMType::Jit => "JIT",
+			VMType::Interpreter => "INT"
+		})
+	}
+}
+
+impl VMType {
+	#[cfg(feature="jit")]
+	pub fn all() -> Vec<VMType> {
+		vec![VMType::Jit, VMType::Interpreter]
+	}
+	#[cfg(not(feature="jit"))]
+	pub fn all() -> Vec<VMType> {
+		vec![VMType::Interpreter]
+	}
+}
+
 /// Evm factory. Creates appropriate Evm.
-pub struct Factory;
+pub struct Factory {
+	evm : VMType
+}
 
 impl Factory {
-	/// Returns jit vm
+
+	pub fn create(&self) -> Box<Evm> {
+		match self.evm {
+			VMType::Jit => {
+				Factory::jit()
+			},
+			VMType::Interpreter => {
+				Box::new(super::interpreter::Interpreter)
+			}
+		}	
+	}
+
+	pub fn new(evm: VMType) -> Factory {
+		Factory {
+			evm: evm
+		}
+	}
+
 	#[cfg(feature = "jit")]
-	pub fn create() -> Box<Evm> {
+	fn jit() -> Box<Evm> {
 		Box::new(super::jit::JitEvm)
 	}
 
-	/// Returns native rust evm
 	#[cfg(not(feature = "jit"))]
-	pub fn create() -> Box<Evm> {
-		Box::new(super::interpreter::Interpreter)
+	fn jit() -> Box<Evm> {
+		unimplemented!()
+	}
+
+	/// Returns jitvm factory
+	#[cfg(feature = "jit")]
+	pub fn default() -> Factory {
+		Factory {
+			evm: VMType::Jit
+		}
+	}
+
+	/// Returns native rust evm factory
+	#[cfg(not(feature = "jit"))]
+	pub fn default() -> Factory {
+		Factory {
+			evm: VMType::Interpreter
+		}
 	}
 }
 
 #[test]
 fn test_create_vm() {
-	let _vm = Factory::create();
+	let _vm = Factory::default().create();
 }
+
+#[macro_export]
+macro_rules! evm_test(
+	($name_test: ident: $name_jit: ident, $name_int: ident) => {
+		#[test]
+		#[cfg(feature = "jit")]
+		fn $name_jit() {
+			$name_test(Factory::new(VMType::Jit));
+		}
+		#[test]
+		fn $name_int() {
+			$name_test(Factory::new(VMType::Interpreter));
+		}
+	}
+);
diff --git a/src/evm/mod.rs b/src/evm/mod.rs
index 118e98f8a..5f3f362a2 100644
--- a/src/evm/mod.rs
+++ b/src/evm/mod.rs
@@ -3,6 +3,7 @@
 pub mod ext;
 pub mod evm;
 pub mod interpreter;
+#[macro_use]
 pub mod factory;
 pub mod schedule;
 mod instructions;
@@ -16,3 +17,4 @@ pub use self::evm::{Evm, Error, Result};
 pub use self::ext::Ext;
 pub use self::factory::Factory;
 pub use self::schedule::Schedule;
+pub use self::factory::VMType;
diff --git a/src/evm/tests.rs b/src/evm/tests.rs
index ab5dd9dbd..a818a38fc 100644
--- a/src/evm/tests.rs
+++ b/src/evm/tests.rs
@@ -1,6 +1,6 @@
 use common::*;
 use evm;
-use evm::{Ext, Schedule};
+use evm::{Ext, Schedule, Factory, VMType};
 
 struct FakeLogEntry {
 	topics: Vec<H256>,
@@ -122,22 +122,8 @@ fn test_stack_underflow() {
 	};
 }
 
-macro_rules! evm_test(
-	($name_test: ident: $name_jit: ident, $name_int: ident) => {
-		#[test]
-		#[cfg(feature = "jit")]
-		fn $name_jit() {
-			$name_test(Box::new(super::jit::JitEvm));
-		}
-		#[test]
-		fn $name_int() {
-			$name_test(Box::new(super::interpreter::Interpreter));
-		}
-	}
-);
-
 evm_test!{test_add: test_add_jit, test_add_int}
-fn test_add(vm : Box<super::Evm>) {
+fn test_add(factory: super::Factory) {
   let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff01600055".from_hex().unwrap();
 
@@ -148,6 +134,7 @@ fn test_add(vm : Box<super::Evm>) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -156,7 +143,7 @@ fn test_add(vm : Box<super::Evm>) {
 }
 
 evm_test!{test_sha3: test_sha3_jit, test_sha3_int}
-fn test_sha3(vm: Box<super::Evm>) {
+fn test_sha3(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "6000600020600055".from_hex().unwrap();
 
@@ -167,6 +154,7 @@ fn test_sha3(vm: Box<super::Evm>) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -175,7 +163,7 @@ fn test_sha3(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_address: test_address_jit, test_address_int}
-fn test_address(vm: Box<super::Evm>) {
+fn test_address(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "30600055".from_hex().unwrap();
 
@@ -186,6 +174,7 @@ fn test_address(vm: Box<super::Evm>) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -194,7 +183,7 @@ fn test_address(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_origin: test_origin_jit, test_origin_int}
-fn test_origin(vm: Box<super::Evm>) {
+fn test_origin(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let origin = Address::from_str("cd1722f2947def4cf144679da39c4c32bdc35681").unwrap();
 	let code = "32600055".from_hex().unwrap();
@@ -207,6 +196,7 @@ fn test_origin(vm: Box<super::Evm>) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -215,7 +205,7 @@ fn test_origin(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_sender: test_sender_jit, test_sender_int}
-fn test_sender(vm: Box<super::Evm>) {
+fn test_sender(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let sender = Address::from_str("cd1722f2947def4cf144679da39c4c32bdc35681").unwrap();
 	let code = "33600055".from_hex().unwrap();
@@ -228,6 +218,7 @@ fn test_sender(vm: Box<super::Evm>) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -236,7 +227,7 @@ fn test_sender(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_extcodecopy: test_extcodecopy_jit, test_extcodecopy_int}
-fn test_extcodecopy(vm: Box<super::Evm>) {
+fn test_extcodecopy(factory: super::Factory) {
 		// 33 - sender
 		// 3b - extcodesize
 		// 60 00 - push 0
@@ -262,6 +253,7 @@ fn test_extcodecopy(vm: Box<super::Evm>) {
 	ext.codes.insert(sender, sender_code);
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -270,7 +262,7 @@ fn test_extcodecopy(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_log_empty: test_log_empty_jit, test_log_empty_int}
-fn test_log_empty(vm: Box<super::Evm>) {
+fn test_log_empty(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "60006000a0".from_hex().unwrap();
 
@@ -281,6 +273,7 @@ fn test_log_empty(vm: Box<super::Evm>) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -291,7 +284,7 @@ fn test_log_empty(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_log_sender: test_log_sender_jit, test_log_sender_int}
-fn test_log_sender(vm: Box<super::Evm>) {
+fn test_log_sender(factory: super::Factory) {
 	// 60 ff - push ff
 	// 60 00 - push 00
 	// 53 - mstore 
@@ -312,6 +305,7 @@ fn test_log_sender(vm: Box<super::Evm>) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -323,7 +317,7 @@ fn test_log_sender(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_blockhash: test_blockhash_jit, test_blockhash_int}
-fn test_blockhash(vm: Box<super::Evm>) {
+fn test_blockhash(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "600040600055".from_hex().unwrap();
 	let blockhash = H256::from_str("123400000000000000000000cd1722f2947def4cf144679da39c4c32bdc35681").unwrap();
@@ -336,6 +330,7 @@ fn test_blockhash(vm: Box<super::Evm>) {
 	ext.blockhashes.insert(U256::zero(), blockhash.clone());
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -344,7 +339,7 @@ fn test_blockhash(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_calldataload: test_calldataload_jit, test_calldataload_int}
-fn test_calldataload(vm: Box<super::Evm>) {
+fn test_calldataload(factory: super::Factory) {
 	let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "600135600055".from_hex().unwrap();
 	let data = "0123ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff23".from_hex().unwrap();
@@ -357,6 +352,7 @@ fn test_calldataload(vm: Box<super::Evm>) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -366,7 +362,7 @@ fn test_calldataload(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_author: test_author_jit, test_author_int}
-fn test_author(vm: Box<super::Evm>) {
+fn test_author(factory: super::Factory) {
 	let author = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 	let code = "41600055".from_hex().unwrap();
 
@@ -377,6 +373,7 @@ fn test_author(vm: Box<super::Evm>) {
 	ext.info.author = author;
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -385,7 +382,7 @@ fn test_author(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_timestamp: test_timestamp_jit, test_timestamp_int}
-fn test_timestamp(vm: Box<super::Evm>) {
+fn test_timestamp(factory: super::Factory) {
 	let timestamp = 0x1234; 
 	let code = "42600055".from_hex().unwrap();
 
@@ -396,6 +393,7 @@ fn test_timestamp(vm: Box<super::Evm>) {
 	ext.info.timestamp = timestamp;
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -404,7 +402,7 @@ fn test_timestamp(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_number: test_number_jit, test_number_int}
-fn test_number(vm: Box<super::Evm>) {
+fn test_number(factory: super::Factory) {
 	let number = 0x1234; 
 	let code = "43600055".from_hex().unwrap();
 
@@ -415,6 +413,7 @@ fn test_number(vm: Box<super::Evm>) {
 	ext.info.number = number;
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -423,7 +422,7 @@ fn test_number(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_difficulty: test_difficulty_jit, test_difficulty_int}
-fn test_difficulty(vm: Box<super::Evm>) {
+fn test_difficulty(factory: super::Factory) {
 	let difficulty = U256::from(0x1234);
 	let code = "44600055".from_hex().unwrap();
 
@@ -434,6 +433,7 @@ fn test_difficulty(vm: Box<super::Evm>) {
 	ext.info.difficulty = difficulty;
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
@@ -442,7 +442,7 @@ fn test_difficulty(vm: Box<super::Evm>) {
 }
 
 evm_test!{test_gas_limit: test_gas_limit_jit, test_gas_limit_int}
-fn test_gas_limit(vm: Box<super::Evm>) {
+fn test_gas_limit(factory: super::Factory) {
 	let gas_limit = U256::from(0x1234);
 	let code = "45600055".from_hex().unwrap();
 
@@ -453,6 +453,7 @@ fn test_gas_limit(vm: Box<super::Evm>) {
 	ext.info.gas_limit = gas_limit;
 
 	let gas_left = {
+		let vm = factory.create();
 		vm.exec(&params, &mut ext).unwrap()
 	};
 
diff --git a/src/executive.rs b/src/executive.rs
index f396d49b1..6fe78f165 100644
--- a/src/executive.rs
+++ b/src/executive.rs
@@ -2,7 +2,7 @@
 use common::*;
 use state::*;
 use engine::*;
-use evm::{self, Schedule, Factory, Ext};
+use evm::{self, Schedule, Ext};
 
 /// Returns new address created from address and given nonce.
 pub fn contract_address(address: &Address, nonce: &U256) -> Address {
@@ -196,8 +196,7 @@ impl<'a> Executive<'a> {
 		} else if params.code.len() > 0 {
 			// if destination is a contract, do normal message call
 			let mut ext = Externalities::from_executive(self, params, substate, OutputPolicy::Return(output));
-			let evm = Factory::create();
-			evm.exec(&params, &mut ext)
+			self.engine.vm_factory().create().exec(&params, &mut ext)
 		} else {
 			// otherwise, nothing
 			Ok(params.gas)
@@ -214,8 +213,7 @@ impl<'a> Executive<'a> {
 		self.state.transfer_balance(&params.sender, &params.address, &params.value);
 
 		let mut ext = Externalities::from_executive(self, params, substate, OutputPolicy::InitContract);
-		let evm = Factory::create();
-		evm.exec(&params, &mut ext)
+		self.engine.vm_factory().create().exec(&params, &mut ext)
 	}
 
 	/// Finalizes the transaction (does refunds and suicides).
@@ -309,7 +307,7 @@ impl<'a> Externalities<'a> {
 	/// Basic `Externalities` constructor.
 	pub fn new(state: &'a mut State, 
 			   info: &'a EnvInfo, 
-			   engine: &'a Engine, 
+			   engine: &'a Engine,
 			   depth: usize,
 			   params: &'a ActionParams, 
 			   substate: &'a mut Substate, 
@@ -496,15 +494,19 @@ mod tests {
 	use engine::*;
 	use spec::*;
 	use evm::Schedule;
+	use evm::Factory;
+	use evm::factory::VMType;
 
 	struct TestEngine {
+		factory: Factory,
 		spec: Spec,
 		max_depth: usize
 	}
 
 	impl TestEngine {
-		fn new(max_depth: usize) -> TestEngine {
+		fn new(max_depth: usize, factory: Factory) -> TestEngine {
 			TestEngine {
+				factory: factory,
 				spec: ethereum::new_frontier_test(),
 				max_depth: max_depth 
 			}
@@ -514,6 +516,9 @@ mod tests {
 	impl Engine for TestEngine {
 		fn name(&self) -> &str { "TestEngine" }
 		fn spec(&self) -> &Spec { &self.spec }
+		fn vm_factory(&self) -> &Factory {
+			&self.factory
+		}
 		fn schedule(&self, _env_info: &EnvInfo) -> Schedule { 
 			let mut schedule = Schedule::new_frontier();
 			schedule.max_depth = self.max_depth;
@@ -528,9 +533,9 @@ mod tests {
 		assert_eq!(expected_address, contract_address(&address, &U256::from(88)));
 	}
 
-	#[test]
 	// TODO: replace params with transactions!
-	fn test_sender_balance() {
+	evm_test!{test_sender_balance: test_sender_balance_jit, test_sender_balance_int}
+	fn test_sender_balance(factory: Factory) {
 		let sender = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
 		let address = contract_address(&sender, &U256::zero());
 		let mut params = ActionParams::new();
@@ -542,7 +547,7 @@ mod tests {
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from(0x100u64));
 		let info = EnvInfo::new();
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 		let mut substate = Substate::new();
 
 		let gas_left = {
@@ -560,8 +565,8 @@ mod tests {
 		// TODO: just test state root.
 	}
 
-	#[test]
-	fn test_create_contract() {
+	evm_test!{test_create_contract: test_create_contract_jit, test_create_contract_int}
+	fn test_create_contract(factory: Factory) {
 		// code:
 		//
 		// 7c 601080600c6000396000f3006000355415600957005b60203560003555 - push 29 bytes?
@@ -600,7 +605,7 @@ mod tests {
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from(100));
 		let info = EnvInfo::new();
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 		let mut substate = Substate::new();
 
 		let gas_left = {
@@ -613,8 +618,8 @@ mod tests {
 		assert_eq!(substate.contracts_created.len(), 0);
 	}
 
-	#[test]
-	fn test_create_contract_value_too_high() {
+	evm_test!{test_create_contract_value_too_high: test_create_contract_value_too_high_jit, test_create_contract_value_too_high_int}
+	fn test_create_contract_value_too_high(factory: Factory) {
 		// code:
 		//
 		// 7c 601080600c6000396000f3006000355415600957005b60203560003555 - push 29 bytes?
@@ -653,7 +658,7 @@ mod tests {
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from(100));
 		let info = EnvInfo::new();
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 		let mut substate = Substate::new();
 
 		let gas_left = {
@@ -665,8 +670,8 @@ mod tests {
 		assert_eq!(substate.contracts_created.len(), 0);
 	}
 
-	#[test]
-	fn test_create_contract_without_max_depth() {
+	evm_test!{test_create_contract_without_max_depth: test_create_contract_without_max_depth_jit, test_create_contract_without_max_depth_int}
+	fn test_create_contract_without_max_depth(factory: Factory) {
 		// code:
 		//
 		// 7c 601080600c6000396000f3006000355415600957005b60203560003555 - push 29 bytes?
@@ -704,7 +709,7 @@ mod tests {
 		let mut state = State::new_temp();
 		state.add_balance(&sender, &U256::from(100));
 		let info = EnvInfo::new();
-		let engine = TestEngine::new(1024);
+		let engine = TestEngine::new(1024, factory);
 		let mut substate = Substate::new();
 
 		{
@@ -716,8 +721,8 @@ mod tests {
 		assert_eq!(substate.contracts_created[0], next_address);
 	}
 
-	#[test]
-	fn test_aba_calls() {
+	evm_test!{test_aba_calls: test_aba_calls_jit, test_aba_calls_int}
+	fn test_aba_calls(factory: Factory) {
 		// 60 00 - push 0
 		// 60 00 - push 0
 		// 60 00 - push 0
@@ -762,7 +767,7 @@ mod tests {
 		state.add_balance(&sender, &U256::from(100_000));
 
 		let info = EnvInfo::new();
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 		let mut substate = Substate::new();
 
 		let gas_left = {
@@ -774,8 +779,8 @@ mod tests {
 		assert_eq!(state.storage_at(&address_a, &H256::from(&U256::from(0x23))), H256::from(&U256::from(1)));
 	}
 
-	#[test]
-	fn test_recursive_bomb1() {
+	evm_test!{test_recursive_bomb1: test_recursive_bomb1_jit, test_recursive_bomb1_int}
+	fn test_recursive_bomb1(factory: Factory) {
 		// 60 01 - push 1
 		// 60 00 - push 0
 		// 54 - sload 
@@ -804,7 +809,7 @@ mod tests {
 		let mut state = State::new_temp();
 		state.init_code(&address, code.clone());
 		let info = EnvInfo::new();
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 		let mut substate = Substate::new();
 
 		let gas_left = {
@@ -817,8 +822,8 @@ mod tests {
 		assert_eq!(state.storage_at(&address, &H256::from(&U256::one())), H256::from(&U256::from(1)));
 	}
 
-	#[test]
-	fn test_transact_simple() {
+	evm_test!{test_transact_simple: test_transact_simple_jit, test_transact_simple_int}
+	fn test_transact_simple(factory: Factory) {
 		let mut t = Transaction::new_create(U256::from(17), "3331600055".from_hex().unwrap(), U256::from(100_000), U256::zero(), U256::zero());
 		let keypair = KeyPair::create().unwrap();
 		t.sign(&keypair.secret());
@@ -829,7 +834,7 @@ mod tests {
 		state.add_balance(&sender, &U256::from(18));	
 		let mut info = EnvInfo::new();
 		info.gas_limit = U256::from(100_000);
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 
 		let executed = {
 			let mut ex = Executive::new(&mut state, &info, &engine);
@@ -837,9 +842,9 @@ mod tests {
 		};
 
 		assert_eq!(executed.gas, U256::from(100_000));
-		assert_eq!(executed.gas_used, U256::from(20_025));
-		assert_eq!(executed.refunded, U256::from(79_975));
-		assert_eq!(executed.cumulative_gas_used, U256::from(20_025));
+		assert_eq!(executed.gas_used, U256::from(41_301));
+		assert_eq!(executed.refunded, U256::from(58_699));
+		assert_eq!(executed.cumulative_gas_used, U256::from(41_301));
 		assert_eq!(executed.logs.len(), 0);
 		assert_eq!(executed.out_of_gas, false);
 		assert_eq!(executed.contracts_created.len(), 0);
@@ -849,14 +854,14 @@ mod tests {
 		assert_eq!(state.storage_at(&contract, &H256::new()), H256::from(&U256::from(1)));
 	}
 
-	#[test]
-	fn test_transact_invalid_sender() {
+	evm_test!{test_transact_invalid_sender: test_transact_invalid_sender_jit, test_transact_invalid_sender_int}
+	fn test_transact_invalid_sender(factory: Factory) {
 		let t = Transaction::new_create(U256::from(17), "3331600055".from_hex().unwrap(), U256::from(100_000), U256::zero(), U256::zero());
 
 		let mut state = State::new_temp();
 		let mut info = EnvInfo::new();
 		info.gas_limit = U256::from(100_000);
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 
 		let res = {
 			let mut ex = Executive::new(&mut state, &info, &engine);
@@ -869,8 +874,8 @@ mod tests {
 		}
 	}
 
-	#[test]
-	fn test_transact_invalid_nonce() {
+	evm_test!{test_transact_invalid_nonce: test_transact_invalid_nonce_jit, test_transact_invalid_nonce_int}
+	fn test_transact_invalid_nonce(factory: Factory) {
 		let mut t = Transaction::new_create(U256::from(17), "3331600055".from_hex().unwrap(), U256::from(100_000), U256::zero(), U256::one());
 		let keypair = KeyPair::create().unwrap();
 		t.sign(&keypair.secret());
@@ -880,7 +885,7 @@ mod tests {
 		state.add_balance(&sender, &U256::from(17));	
 		let mut info = EnvInfo::new();
 		info.gas_limit = U256::from(100_000);
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 
 		let res = {
 			let mut ex = Executive::new(&mut state, &info, &engine);
@@ -894,8 +899,8 @@ mod tests {
 		}
 	}
 
-	#[test]
-	fn test_transact_gas_limit_reached() {
+	evm_test!{test_transact_gas_limit_reached: test_transact_gas_limit_reached_jit, test_transact_gas_limit_reached_int}
+	fn test_transact_gas_limit_reached(factory: Factory) {
 		let mut t = Transaction::new_create(U256::from(17), "3331600055".from_hex().unwrap(), U256::from(80_001), U256::zero(), U256::zero());
 		let keypair = KeyPair::create().unwrap();
 		t.sign(&keypair.secret());
@@ -906,7 +911,7 @@ mod tests {
 		let mut info = EnvInfo::new();
 		info.gas_used = U256::from(20_000);
 		info.gas_limit = U256::from(100_000);
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 
 		let res = {
 			let mut ex = Executive::new(&mut state, &info, &engine);
@@ -920,8 +925,8 @@ mod tests {
 		}
 	}
 
-	#[test]
-	fn test_not_enough_cash() {
+	evm_test!{test_not_enough_cash: test_not_enough_cash_jit, test_not_enough_cash_int}
+	fn test_not_enough_cash(factory: Factory) {
 		let mut t = Transaction::new_create(U256::from(18), "3331600055".from_hex().unwrap(), U256::from(100_000), U256::one(), U256::zero());
 		let keypair = KeyPair::create().unwrap();
 		t.sign(&keypair.secret());
@@ -931,7 +936,7 @@ mod tests {
 		state.add_balance(&sender, &U256::from(100_017));	
 		let mut info = EnvInfo::new();
 		info.gas_limit = U256::from(100_000);
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, factory);
 
 		let res = {
 			let mut ex = Executive::new(&mut state, &info, &engine);
diff --git a/src/lib.rs b/src/lib.rs
index 8610404d2..e3c8a5274 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -88,6 +88,8 @@ extern crate env_logger;
 
 pub mod common;
 pub mod basic_types;
+#[macro_use]
+pub mod evm;
 pub mod executive;
 pub mod error;
 pub mod log_entry;
@@ -105,7 +107,6 @@ pub mod spec;
 pub mod views;
 pub mod blockchain;
 pub mod extras;
-pub mod evm;
 
 #[cfg(test)]
 mod tests;
diff --git a/src/null_engine.rs b/src/null_engine.rs
index bd745365c..e673563b3 100644
--- a/src/null_engine.rs
+++ b/src/null_engine.rs
@@ -1,20 +1,29 @@
 use engine::Engine;
 use spec::Spec;
 use evm::Schedule;
+use evm::Factory;
 use env_info::EnvInfo;
 
 /// An engine which does not provide any consensus mechanism.
 pub struct NullEngine {
 	spec: Spec,
+	factory: Factory
 }
 
 impl NullEngine {
 	pub fn new_boxed(spec: Spec) -> Box<Engine> {
-		Box::new(NullEngine{spec: spec})
+		Box::new(NullEngine{
+			spec: spec,
+			// TODO [todr] should this return any specific factory?
+			factory: Factory::default()
+		})
 	}
 }
 
 impl Engine for NullEngine {
+	fn vm_factory(&self) -> &Factory {
+		&self.factory
+	}
 	fn name(&self) -> &str { "NullEngine" }
 	fn spec(&self) -> &Spec { &self.spec }
 	fn schedule(&self, _env_info: &EnvInfo) -> Schedule { Schedule::new_frontier() }
diff --git a/src/tests/executive.rs b/src/tests/executive.rs
index d49ac5f8b..609ac5f03 100644
--- a/src/tests/executive.rs
+++ b/src/tests/executive.rs
@@ -4,17 +4,19 @@ use executive::*;
 use spec::*;
 use engine::*;
 use evm;
-use evm::{Schedule, Ext, Factory};
+use evm::{Schedule, Ext, Factory, VMType};
 use ethereum;
 
 struct TestEngine {
+	vm_factory: Factory,
 	spec: Spec,
 	max_depth: usize
 }
 
 impl TestEngine {
-	fn new(max_depth: usize) -> TestEngine {
+	fn new(max_depth: usize, vm_type: VMType) -> TestEngine {
 		TestEngine {
+			vm_factory: Factory::new(vm_type),
 			spec: ethereum::new_frontier_test(),
 			max_depth: max_depth 
 		}
@@ -24,6 +26,7 @@ impl TestEngine {
 impl Engine for TestEngine {
 	fn name(&self) -> &str { "TestEngine" }
 	fn spec(&self) -> &Spec { &self.spec }
+	fn vm_factory(&self) -> &Factory { &self.vm_factory }
 	fn schedule(&self, _env_info: &EnvInfo) -> Schedule { 
 		let mut schedule = Schedule::new_frontier();
 		schedule.max_depth = self.max_depth; 
@@ -153,16 +156,28 @@ impl<'a> Ext for TestExt<'a> {
 }
 
 fn do_json_test(json_data: &[u8]) -> Vec<String> {
+	let vms = VMType::all();
+	
+	vms
+		.iter()
+		.flat_map(|vm| do_json_test_for(vm, json_data))
+		.collect()
+}
+
+fn do_json_test_for(vm: &VMType, json_data: &[u8]) -> Vec<String> {
 	let json = Json::from_str(::std::str::from_utf8(json_data).unwrap()).expect("Json is invalid");
 	let mut failed = Vec::new();
 	for (name, test) in json.as_object().unwrap() {
 		// sync io is usefull when something crashes in jit
-		//::std::io::stdout().write(&name.as_bytes());
-		//::std::io::stdout().write(b"\n");
-		//::std::io::stdout().flush();
+		// ::std::io::stdout().write(&name.as_bytes());
+		// ::std::io::stdout().write(b"\n");
+		// ::std::io::stdout().flush();
 		let mut fail = false;
 		//let mut fail_unless = |cond: bool| if !cond && !fail { failed.push(name.to_string()); fail = true };
-		let mut fail_unless = |cond: bool, s: &str | if !cond && !fail { failed.push(name.to_string() + ": "+ s); fail = true };
+		let mut fail_unless = |cond: bool, s: &str | if !cond && !fail { 
+			failed.push(format!("[{}] {}: {}", vm, name.to_string(), s)); 
+			fail = true 
+		};
 	
 		// test env
 		let mut state = State::new_temp();
@@ -194,7 +209,7 @@ fn do_json_test(json_data: &[u8]) -> Vec<String> {
 			info.timestamp = u256_from_json(&env["currentTimestamp"]).low_u64();
 		});
 
-		let engine = TestEngine::new(0);
+		let engine = TestEngine::new(0, vm.clone());
 
 		// params
 		let mut params = ActionParams::new();
@@ -219,7 +234,7 @@ fn do_json_test(json_data: &[u8]) -> Vec<String> {
 		let (res, callcreates) = {
 			let ex = Externalities::new(&mut state, &info, &engine, 0, &params, &mut substate, OutputPolicy::Return(BytesRef::Flexible(&mut output)));
 			let mut test_ext = TestExt::new(ex);
-			let evm = Factory::create();
+			let evm = engine.vm_factory().create();
 			let res = evm.exec(&params, &mut test_ext);
 			(res, test_ext.callcreates)
 		};
diff --git a/src/tests/state.rs b/src/tests/state.rs
index 080bdf979..8adc885da 100644
--- a/src/tests/state.rs
+++ b/src/tests/state.rs
@@ -1,6 +1,5 @@
 use super::test_common::*;
 use state::*;
-use executive::*;
 use ethereum;
 
 fn do_json_test(json_data: &[u8]) -> Vec<String> {
@@ -57,4 +56,4 @@ fn do_json_test(json_data: &[u8]) -> Vec<String> {
 }
 
 declare_test!{StateTests_stExample, "StateTests/stExample"}
-declare_test!{StateTests_stLogTests, "StateTests/stLogTests"}
\ No newline at end of file
+declare_test!{StateTests_stLogTests, "StateTests/stLogTests"}