diff --git a/dapps/src/apps.rs b/dapps/src/apps.rs
index 559282584..130b20fb9 100644
--- a/dapps/src/apps.rs
+++ b/dapps/src/apps.rs
@@ -38,11 +38,16 @@ pub fn utils() -> Box<Endpoint> {
 
 pub fn all_endpoints() -> Endpoints {
 	let mut pages = Endpoints::new();
-	pages.insert("proxy".to_owned(), ProxyPac::boxed());
+	pages.insert("proxy".into(), ProxyPac::boxed());
 
+	// Home page needs to be safe embed
+	// because we use Cross-Origin LocalStorage.
+	// TODO [ToDr] Account naming should be moved to parity.
+	pages.insert("home".into(), Box::new(
+		PageEndpoint::new_safe_to_embed(parity_dapps_builtins::App::default())
+	));
 	insert::<parity_dapps_status::App>(&mut pages, "status");
 	insert::<parity_dapps_status::App>(&mut pages, "parity");
-	insert::<parity_dapps_builtins::App>(&mut pages, "home");
 
 	wallet_page(&mut pages);
 	daodapp_page(&mut pages);
diff --git a/dapps/src/endpoint.rs b/dapps/src/endpoint.rs
index 60708f549..28ca6ea11 100644
--- a/dapps/src/endpoint.rs
+++ b/dapps/src/endpoint.rs
@@ -21,7 +21,7 @@ use hyper::{header, server, Decoder, Encoder, Next};
 use hyper::net::HttpStream;
 
 use std::io::Write;
-use std::collections::HashMap;
+use std::collections::BTreeMap;
 
 #[derive(Debug, PartialEq, Default, Clone)]
 pub struct EndpointPath {
@@ -45,7 +45,7 @@ pub trait Endpoint : Send + Sync {
 	fn to_handler(&self, path: EndpointPath) -> Box<server::Handler<HttpStream>>;
 }
 
-pub type Endpoints = HashMap<String, Box<Endpoint>>;
+pub type Endpoints = BTreeMap<String, Box<Endpoint>>;
 pub type Handler = server::Handler<HttpStream>;
 
 pub struct ContentHandler {
diff --git a/dapps/src/page/mod.rs b/dapps/src/page/mod.rs
index 71989bca7..819988310 100644
--- a/dapps/src/page/mod.rs
+++ b/dapps/src/page/mod.rs
@@ -30,6 +30,8 @@ pub struct PageEndpoint<T : WebApp + 'static> {
 	pub app: Arc<T>,
 	/// Prefix to strip from the path (when `None` deducted from `app_id`)
 	pub prefix: Option<String>,
+	/// Safe to be loaded in frame by other origin. (use wisely!)
+	safe_to_embed: bool,
 }
 
 impl<T: WebApp + 'static> PageEndpoint<T> {
@@ -37,6 +39,7 @@ impl<T: WebApp + 'static> PageEndpoint<T> {
 		PageEndpoint {
 			app: Arc::new(app),
 			prefix: None,
+			safe_to_embed: false,
 		}
 	}
 
@@ -44,6 +47,18 @@ impl<T: WebApp + 'static> PageEndpoint<T> {
 		PageEndpoint {
 			app: Arc::new(app),
 			prefix: Some(prefix),
+			safe_to_embed: false,
+		}
+	}
+
+	/// Creates new `PageEndpoint` which can be safely used in iframe
+	/// even from different origin. It might be dangerous (clickjacking).
+	/// Use wisely!
+	pub fn new_safe_to_embed(app: T) -> Self {
+		PageEndpoint {
+			app: Arc::new(app),
+			prefix: None,
+			safe_to_embed: true,
 		}
 	}
 }
@@ -61,6 +76,7 @@ impl<T: WebApp> Endpoint for PageEndpoint<T> {
 			path: path,
 			file: None,
 			write_pos: 0,
+			safe_to_embed: self.safe_to_embed,
 		})
 	}
 }
@@ -83,6 +99,7 @@ struct PageHandler<T: WebApp + 'static> {
 	path: EndpointPath,
 	file: Option<String>,
 	write_pos: usize,
+	safe_to_embed: bool,
 }
 
 impl<T: WebApp + 'static> PageHandler<T> {
@@ -128,6 +145,9 @@ impl<T: WebApp + 'static> server::Handler<HttpStream> for PageHandler<T> {
 		if let Some(f) = self.file.as_ref().and_then(|f| self.app.file(f)) {
 			res.set_status(StatusCode::Ok);
 			res.headers_mut().set(header::ContentType(f.content_type.parse().unwrap()));
+			if !self.safe_to_embed {
+				res.headers_mut().set_raw("X-Frame-Options", vec![b"SAMEORIGIN".to_vec()]);
+			}
 			Next::write()
 		} else {
 			res.set_status(StatusCode::NotFound);
@@ -192,6 +212,7 @@ fn should_extract_path_with_appid() {
 		},
 		file: None,
 		write_pos: 0,
+		safe_to_embed: true,
 	};
 
 	// when
diff --git a/db/Cargo.toml b/db/Cargo.toml
index 8bd26d1f9..24d0e6fbe 100644
--- a/db/Cargo.toml
+++ b/db/Cargo.toml
@@ -8,17 +8,19 @@ authors = ["Ethcore <admin@ethcore.io>"]
 build = "build.rs"
 
 [build-dependencies]
-syntex = "*"
+syntex = "0.32"
 ethcore-ipc-codegen = { path = "../ipc/codegen" }
 
 [dependencies]
-ethcore-util = { path = "../util" }
 clippy = { version = "0.0.67", optional = true}
 ethcore-devtools = { path = "../devtools" }
 ethcore-ipc = { path = "../ipc/rpc" }
 rocksdb = { git = "https://github.com/ethcore/rust-rocksdb" }
 semver = "0.2"
 ethcore-ipc-nano = { path = "../ipc/nano" }
+nanomsg = { git = "https://github.com/ethcore/nanomsg.rs.git" }
+crossbeam = "0.2"
+ethcore-util = { path = "../util" }
 
 [features]
 dev = ["clippy"]
diff --git a/db/src/database.rs b/db/src/database.rs
index 4abc98467..d535f1f56 100644
--- a/db/src/database.rs
+++ b/db/src/database.rs
@@ -18,15 +18,13 @@
 
 use traits::*;
 use rocksdb::{DB, Writable, WriteBatch, IteratorMode, DBIterator,
-	IndexType, Options, DBCompactionStyle, BlockBasedOptions, Direction};
-use std::collections::BTreeMap;
-use std::sync::{RwLock};
+IndexType, Options, DBCompactionStyle, BlockBasedOptions, Direction};
+use std::sync::{RwLock, Arc};
 use std::convert::From;
 use ipc::IpcConfig;
-use std::ops::*;
 use std::mem;
 use ipc::binary::BinaryConvertError;
-use std::collections::VecDeque;
+use std::collections::{VecDeque, HashMap, BTreeMap};
 
 impl From<String> for Error {
 	fn from(s: String) -> Error {
@@ -34,20 +32,136 @@ impl From<String> for Error {
 	}
 }
 
+enum WriteCacheEntry {
+	Remove,
+	Write(Vec<u8>),
+}
+
+pub struct WriteCache {
+	entries: HashMap<Vec<u8>, WriteCacheEntry>,
+	preferred_len: usize,
+}
+
+const FLUSH_BATCH_SIZE: usize = 4096;
+
+impl WriteCache {
+	fn new(cache_len: usize) -> WriteCache {
+		WriteCache {
+			entries: HashMap::new(),
+			preferred_len: cache_len,
+		}
+	}
+
+	fn write(&mut self, key: Vec<u8>, val: Vec<u8>) {
+		self.entries.insert(key, WriteCacheEntry::Write(val));
+	}
+
+	fn remove(&mut self, key: Vec<u8>) {
+		self.entries.insert(key, WriteCacheEntry::Remove);
+	}
+
+	fn get(&self, key: &Vec<u8>) -> Option<Vec<u8>> {
+		self.entries.get(key).and_then(
+			|vec_ref| match vec_ref {
+				&WriteCacheEntry::Write(ref val) => Some(val.clone()),
+				&WriteCacheEntry::Remove => None
+			})
+	}
+
+	/// WriteCache should be locked for this
+	fn flush(&mut self, db: &DB, amount: usize) -> Result<(), Error> {
+		let batch = WriteBatch::new();
+		let mut removed_so_far = 0;
+		while removed_so_far < amount {
+			if self.entries.len() == 0 { break; }
+			let removed_key = {
+				let (key, cache_entry) = self.entries.iter().nth(0)
+				.expect("if entries.len == 0, we should have break in the loop, still we got here somehow");
+
+				match *cache_entry {
+					WriteCacheEntry::Write(ref val) => {
+						try!(batch.put(&key, val));
+					},
+					WriteCacheEntry::Remove => {
+						try!(batch.delete(&key));
+					},
+				}
+				key.clone()
+			};
+
+			self.entries.remove(&removed_key);
+
+			removed_so_far = removed_so_far + 1;
+		}
+		if removed_so_far > 0 {
+			try!(db.write(batch));
+		}
+		Ok(())
+	}
+
+	/// flushes until cache is empty
+	fn flush_all(&mut self, db: &DB) -> Result<(), Error> {
+		while !self.is_empty() { try!(self.flush(db, FLUSH_BATCH_SIZE)); }
+		Ok(())
+	}
+
+	fn is_empty(&self) -> bool {
+		self.entries.is_empty()
+	}
+
+	fn try_shrink(&mut self, db: &DB) -> Result<(), Error> {
+		if self.entries.len() > self.preferred_len {
+			try!(self.flush(db, FLUSH_BATCH_SIZE));
+		}
+		Ok(())
+	}
+}
+
 pub struct Database {
 	db: RwLock<Option<DB>>,
-	transactions: RwLock<BTreeMap<TransactionHandle, WriteBatch>>,
+	/// Iterators - dont't use between threads!
 	iterators: RwLock<BTreeMap<IteratorHandle, DBIterator>>,
+	write_cache: RwLock<WriteCache>,
 }
 
+unsafe impl Send for Database {}
+unsafe impl Sync for Database {}
+
 impl Database {
 	pub fn new() -> Database {
 		Database {
 			db: RwLock::new(None),
-			transactions: RwLock::new(BTreeMap::new()),
 			iterators: RwLock::new(BTreeMap::new()),
+			write_cache: RwLock::new(WriteCache::new(DEFAULT_CACHE_LEN)),
 		}
 	}
+
+	pub fn flush(&self) -> Result<(), Error> {
+		let mut cache_lock = self.write_cache.write().unwrap();
+		let db_lock = self.db.read().unwrap();
+		if db_lock.is_none() { return Ok(()); }
+		let db = db_lock.as_ref().unwrap();
+
+		try!(cache_lock.try_shrink(&db));
+		Ok(())
+	}
+
+	pub fn flush_all(&self) -> Result<(), Error> {
+		let mut cache_lock = self.write_cache.write().unwrap();
+		let db_lock = self.db.read().unwrap();
+		if db_lock.is_none() { return Ok(()); }
+		let db = db_lock.as_ref().expect("we should have exited with Ok(()) on the previous step");
+
+		try!(cache_lock.flush_all(&db));
+		Ok(())
+
+	}
+}
+
+impl Drop for Database {
+	fn drop(&mut self) {
+		self.flush().unwrap();
+	}
 }
 
 #[derive(Ipc)]
@@ -72,51 +186,64 @@ impl DatabaseService for Database {
 		Ok(())
 	}
 
+	/// Opens database in the specified path with the default config
+	fn open_default(&self, path: String) -> Result<(), Error> {
+		self.open(DatabaseConfig::default(), path)
+	}
+
 	fn close(&self) -> Result<(), Error> {
+		try!(self.flush_all());
+
 		let mut db = self.db.write().unwrap();
 		if db.is_none() { return Err(Error::IsClosed); }
 
-		// TODO: wait for transactions to expire/close here?
-		if self.transactions.read().unwrap().len() > 0 { return Err(Error::UncommitedTransactions); }
-
 		*db = None;
 		Ok(())
 	}
 
 	fn put(&self, key: &[u8], value: &[u8]) -> Result<(), Error> {
-		let db_lock = self.db.read().unwrap();
-		let db = try!(db_lock.as_ref().ok_or(Error::IsClosed));
-
-		try!(db.put(key, value));
+		let mut cache_lock = self.write_cache.write().unwrap();
+		cache_lock.write(key.to_vec(), value.to_vec());
 		Ok(())
 	}
 
 	fn delete(&self, key: &[u8]) -> Result<(), Error> {
-		let db_lock = self.db.read().unwrap();
-		let db = try!(db_lock.as_ref().ok_or(Error::IsClosed));
-
-		try!(db.delete(key));
+		let mut cache_lock = self.write_cache.write().unwrap();
+		cache_lock.remove(key.to_vec());
 		Ok(())
 	}
 
-	fn write(&self, handle: TransactionHandle) -> Result<(), Error> {
-		let db_lock = self.db.read().unwrap();
-		let db = try!(db_lock.as_ref().ok_or(Error::IsClosed));
+	fn write(&self, transaction: DBTransaction) -> Result<(), Error> {
+		let mut cache_lock = self.write_cache.write().unwrap();
 
-		let mut transactions = self.transactions.write().unwrap();
-		let batch = try!(
-			transactions.remove(&handle).ok_or(Error::TransactionUnknown)
-		);
-		try!(db.write(batch));
+		let mut writes = transaction.writes.borrow_mut();
+		for kv in writes.drain(..) {
+			cache_lock.write(kv.key, kv.value);
+		}
+
+		let mut removes = transaction.removes.borrow_mut();
+		for k in removes.drain(..) {
+			cache_lock.remove(k);
+		}
 		Ok(())
 	}
 
 	fn get(&self, key: &[u8]) -> Result<Option<Vec<u8>>, Error> {
+		{
+			let key_vec = key.to_vec();
+			let cache_hit = self.write_cache.read().unwrap().get(&key_vec);
+
+			if cache_hit.is_some() {
+				return Ok(Some(cache_hit.expect("cache_hit.is_some() = true, still there is none somehow here")))
+			}
+		}
 		let db_lock = self.db.read().unwrap();
 		let db = try!(db_lock.as_ref().ok_or(Error::IsClosed));
 
 		match try!(db.get(key)) {
-			Some(db_vec) => Ok(Some(db_vec.to_vec())),
+			Some(db_vec) => {
+				Ok(Some(db_vec.to_vec()))
+			},
 			None => Ok(None),
 		}
 	}
@@ -166,37 +293,35 @@ impl DatabaseService for Database {
 		})
 	}
 
-	fn transaction_put(&self, transaction: TransactionHandle, key: &[u8], value: &[u8]) -> Result<(), Error>
-	{
-		let mut transactions = self.transactions.write().unwrap();
-		let batch = try!(
-			transactions.get_mut(&transaction).ok_or(Error::TransactionUnknown)
-		);
-		try!(batch.put(&key, &value));
+	fn dispose_iter(&self, handle: IteratorHandle) -> Result<(), Error> {
+		let mut iterators = self.iterators.write().unwrap();
+		iterators.remove(&handle);
 		Ok(())
 	}
-
-	fn transaction_delete(&self, transaction: TransactionHandle, key: &[u8]) -> Result<(), Error> {
-		let mut transactions = self.transactions.write().unwrap();
-		let batch = try!(
-			transactions.get_mut(&transaction).ok_or(Error::TransactionUnknown)
-		);
-		try!(batch.delete(&key));
-		Ok(())
-	}
-
-	fn new_transaction(&self) -> TransactionHandle {
-		let mut transactions = self.transactions.write().unwrap();
-		let next_transaction = transactions.keys().last().unwrap_or(&0) + 1;
-		transactions.insert(next_transaction, WriteBatch::new());
-
-		next_transaction
-	}
 }
 
 // TODO : put proper at compile-time
 impl IpcConfig for Database {}
 
+/// Database iterator
+pub struct DatabaseIterator {
+	client: Arc<DatabaseClient<::nanomsg::Socket>>,
+	handle: IteratorHandle,
+}
+
+impl Iterator for DatabaseIterator {
+	type Item = (Vec<u8>, Vec<u8>);
+
+	fn next(&mut self) -> Option<Self::Item> {
+		self.client.iter_next(self.handle).and_then(|kv| Some((kv.key, kv.value)))
+	}
+}
+
+impl Drop for DatabaseIterator {
+	fn drop(&mut self) {
+		self.client.dispose_iter(self.handle).unwrap();
+	}
+}
 
 #[cfg(test)]
 mod test {
@@ -215,7 +340,7 @@ mod test {
 	fn can_be_open_empty() {
 		let db = Database::new();
 		let path = RandomTempPath::create_dir();
-		db.open(DatabaseConfig { prefix_size: Some(8) }, path.as_str().to_owned()).unwrap();
+		db.open_default(path.as_str().to_owned()).unwrap();
 
 		assert!(db.is_empty().is_ok());
 	}
@@ -224,9 +349,10 @@ mod test {
 	fn can_store_key() {
 		let db = Database::new();
 		let path = RandomTempPath::create_dir();
-		db.open(DatabaseConfig { prefix_size: None }, path.as_str().to_owned()).unwrap();
+		db.open_default(path.as_str().to_owned()).unwrap();
 
 		db.put("xxx".as_bytes(), "1".as_bytes()).unwrap();
+		db.flush_all().unwrap();
 		assert!(!db.is_empty().unwrap());
 	}
 
@@ -234,15 +360,37 @@ mod test {
 	fn can_retrieve() {
 		let db = Database::new();
 		let path = RandomTempPath::create_dir();
-		db.open(DatabaseConfig { prefix_size: None }, path.as_str().to_owned()).unwrap();
+		db.open_default(path.as_str().to_owned()).unwrap();
 		db.put("xxx".as_bytes(), "1".as_bytes()).unwrap();
 		db.close().unwrap();
 
-		db.open(DatabaseConfig { prefix_size: None }, path.as_str().to_owned()).unwrap();
+		db.open_default(path.as_str().to_owned()).unwrap();
 		assert_eq!(db.get("xxx".as_bytes()).unwrap().unwrap(), "1".as_bytes().to_vec());
 	}
 }
 
+#[cfg(test)]
+mod write_cache_tests {
+	use super::Database;
+	use traits::*;
+	use devtools::*;
+
+	#[test]
+	fn cache_write_flush() {
+		let db = Database::new();
+		let path = RandomTempPath::create_dir();
+
+		db.open_default(path.as_str().to_owned()).unwrap();
+		db.put("100500".as_bytes(), "1".as_bytes()).unwrap();
+		db.delete("100500".as_bytes()).unwrap();
+		db.flush_all().unwrap();
+
+		let val = db.get("100500".as_bytes()).unwrap();
+		assert!(val.is_none());
+	}
+
+}
+
 #[cfg(test)]
 mod client_tests {
 	use super::{DatabaseClient, Database};
@@ -251,6 +399,8 @@ mod client_tests {
 	use nanoipc;
 	use std::sync::Arc;
 	use std::sync::atomic::{Ordering, AtomicBool};
+	use crossbeam;
+	use run_worker;
 
 	fn init_worker(addr: &str) -> nanoipc::Worker<Database> {
 		let mut worker = nanoipc::Worker::<Database>::new(&Arc::new(Database::new()));
@@ -268,7 +418,7 @@ mod client_tests {
 
 		::std::thread::spawn(move || {
 			let mut worker = init_worker(url);
-    		while !c_worker_should_exit.load(Ordering::Relaxed) {
+			while !c_worker_should_exit.load(Ordering::Relaxed) {
 				worker.poll();
 				c_worker_is_ready.store(true, Ordering::Relaxed);
 			}
@@ -295,7 +445,7 @@ mod client_tests {
 
 		::std::thread::spawn(move || {
 			let mut worker = init_worker(url);
-    		while !c_worker_should_exit.load(Ordering::Relaxed) {
+			while !c_worker_should_exit.load(Ordering::Relaxed) {
 				worker.poll();
 				c_worker_is_ready.store(true, Ordering::Relaxed);
 			}
@@ -304,7 +454,7 @@ mod client_tests {
 		while !worker_is_ready.load(Ordering::Relaxed) { }
 		let client = nanoipc::init_duplex_client::<DatabaseClient<_>>(url).unwrap();
 
-		client.open(DatabaseConfig { prefix_size: Some(8) }, path.as_str().to_owned()).unwrap();
+		client.open_default(path.as_str().to_owned()).unwrap();
 		assert!(client.is_empty().unwrap());
 		worker_should_exit.store(true, Ordering::Relaxed);
 	}
@@ -314,27 +464,16 @@ mod client_tests {
 		let url = "ipc:///tmp/parity-db-ipc-test-30.ipc";
 		let path = RandomTempPath::create_dir();
 
-		let worker_should_exit = Arc::new(AtomicBool::new(false));
-		let worker_is_ready = Arc::new(AtomicBool::new(false));
-		let c_worker_should_exit = worker_should_exit.clone();
-		let c_worker_is_ready = worker_is_ready.clone();
+		crossbeam::scope(move |scope| {
+			let stop = Arc::new(AtomicBool::new(false));
+			run_worker(scope, stop.clone(), url);
+			let client = nanoipc::init_client::<DatabaseClient<_>>(url).unwrap();
+			client.open_default(path.as_str().to_owned()).unwrap();
+			client.put("xxx".as_bytes(), "1".as_bytes()).unwrap();
+			client.close().unwrap();
 
-		::std::thread::spawn(move || {
-			let mut worker = init_worker(url);
-    		while !c_worker_should_exit.load(Ordering::Relaxed) {
-				worker.poll();
-				c_worker_is_ready.store(true, Ordering::Relaxed);
-			}
+			stop.store(true, Ordering::Relaxed);
 		});
-
-		while !worker_is_ready.load(Ordering::Relaxed) { }
-		let client = nanoipc::init_duplex_client::<DatabaseClient<_>>(url).unwrap();
-
-		client.open(DatabaseConfig { prefix_size: Some(8) }, path.as_str().to_owned()).unwrap();
-		client.put("xxx".as_bytes(), "1".as_bytes()).unwrap();
-		client.close().unwrap();
-
-		worker_should_exit.store(true, Ordering::Relaxed);
 	}
 
 	#[test]
@@ -342,29 +481,93 @@ mod client_tests {
 		let url = "ipc:///tmp/parity-db-ipc-test-40.ipc";
 		let path = RandomTempPath::create_dir();
 
-		let worker_should_exit = Arc::new(AtomicBool::new(false));
-		let worker_is_ready = Arc::new(AtomicBool::new(false));
-		let c_worker_should_exit = worker_should_exit.clone();
-		let c_worker_is_ready = worker_is_ready.clone();
+		crossbeam::scope(move |scope| {
+			let stop = Arc::new(AtomicBool::new(false));
+			run_worker(scope, stop.clone(), url);
+			let client = nanoipc::init_client::<DatabaseClient<_>>(url).unwrap();
 
-		::std::thread::spawn(move || {
-			let mut worker = init_worker(url);
-    		while !c_worker_should_exit.load(Ordering::Relaxed) {
-				worker.poll();
-				c_worker_is_ready.store(true, Ordering::Relaxed);
+			client.open_default(path.as_str().to_owned()).unwrap();
+			client.put("xxx".as_bytes(), "1".as_bytes()).unwrap();
+			client.close().unwrap();
+
+			client.open_default(path.as_str().to_owned()).unwrap();
+			assert_eq!(client.get("xxx".as_bytes()).unwrap().unwrap(), "1".as_bytes().to_vec());
+
+			stop.store(true, Ordering::Relaxed);
+		});
+	}
+
+	#[test]
+	fn can_read_empty() {
+		let url = "ipc:///tmp/parity-db-ipc-test-45.ipc";
+		let path = RandomTempPath::create_dir();
+
+		crossbeam::scope(move |scope| {
+			let stop = Arc::new(AtomicBool::new(false));
+			run_worker(scope, stop.clone(), url);
+			let client = nanoipc::init_client::<DatabaseClient<_>>(url).unwrap();
+
+			client.open_default(path.as_str().to_owned()).unwrap();
+			assert!(client.get("xxx".as_bytes()).unwrap().is_none());
+
+			stop.store(true, Ordering::Relaxed);
+		});
+	}
+
+
+	#[test]
+	fn can_commit_client_transaction() {
+		let url = "ipc:///tmp/parity-db-ipc-test-60.ipc";
+		let path = RandomTempPath::create_dir();
+
+		crossbeam::scope(move |scope| {
+			let stop = Arc::new(AtomicBool::new(false));
+			run_worker(scope, stop.clone(), url);
+			let client = nanoipc::init_client::<DatabaseClient<_>>(url).unwrap();
+			client.open_default(path.as_str().to_owned()).unwrap();
+
+			let transaction = DBTransaction::new();
+			transaction.put("xxx".as_bytes(), "1".as_bytes());
+			client.write(transaction).unwrap();
+
+			client.close().unwrap();
+
+			client.open_default(path.as_str().to_owned()).unwrap();
+			assert_eq!(client.get("xxx".as_bytes()).unwrap().unwrap(), "1".as_bytes().to_vec());
+
+			stop.store(true, Ordering::Relaxed);
+		});
+	}
+
+	#[test]
+	fn key_write_read_ipc() {
+		let url = "ipc:///tmp/parity-db-ipc-test-70.ipc";
+		let path = RandomTempPath::create_dir();
+
+		crossbeam::scope(|scope| {
+			let stop = StopGuard::new();
+			run_worker(&scope, stop.share(), url);
+
+			let client = nanoipc::init_client::<DatabaseClient<_>>(url).unwrap();
+
+			client.open_default(path.as_str().to_owned()).unwrap();
+			let mut batch = Vec::new();
+			for _ in 0..100 {
+				batch.push((random_str(256).as_bytes().to_vec(), random_str(256).as_bytes().to_vec()));
+				batch.push((random_str(256).as_bytes().to_vec(), random_str(2048).as_bytes().to_vec()));
+				batch.push((random_str(2048).as_bytes().to_vec(), random_str(2048).as_bytes().to_vec()));
+				batch.push((random_str(2048).as_bytes().to_vec(), random_str(256).as_bytes().to_vec()));
+			}
+
+			for &(ref k, ref v) in batch.iter() {
+				client.put(k, v).unwrap();
+			}
+			client.close().unwrap();
+
+			client.open_default(path.as_str().to_owned()).unwrap();
+			for &(ref k, ref v) in batch.iter() {
+				assert_eq!(v, &client.get(k).unwrap().unwrap());
 			}
 		});
-
-		while !worker_is_ready.load(Ordering::Relaxed) { }
-		let client = nanoipc::init_duplex_client::<DatabaseClient<_>>(url).unwrap();
-
-		client.open(DatabaseConfig { prefix_size: Some(8) }, path.as_str().to_owned()).unwrap();
-		client.put("xxx".as_bytes(), "1".as_bytes()).unwrap();
-		client.close().unwrap();
-
-		client.open(DatabaseConfig { prefix_size: Some(8) }, path.as_str().to_owned()).unwrap();
-		assert_eq!(client.get("xxx".as_bytes()).unwrap().unwrap(), "1".as_bytes().to_vec());
-
-		worker_should_exit.store(true, Ordering::Relaxed);
 	}
 }
diff --git a/db/src/lib.rs.in b/db/src/lib.rs.in
index 694b4e3e1..4fa43b977 100644
--- a/db/src/lib.rs.in
+++ b/db/src/lib.rs.in
@@ -19,7 +19,71 @@ extern crate rocksdb;
 extern crate ethcore_devtools as devtools;
 extern crate semver;
 extern crate ethcore_ipc_nano as nanoipc;
+extern crate nanomsg;
+extern crate crossbeam;
 extern crate ethcore_util as util;
 
 pub mod database;
 pub mod traits;
+
+pub use traits::{DatabaseService, DBTransaction, Error};
+pub use database::{Database, DatabaseClient, DatabaseIterator};
+
+use std::sync::Arc;
+use std::sync::atomic::*;
+use std::path::PathBuf;
+
+pub type DatabaseNanoClient = DatabaseClient<::nanomsg::Socket>;
+pub type DatabaseConnection = nanoipc::GuardedSocket<DatabaseNanoClient>;
+
+#[derive(Debug)]
+pub enum ServiceError {
+	Io(std::io::Error),
+	Socket(nanoipc::SocketError),
+}
+
+impl std::convert::From<std::io::Error> for ServiceError {
+	fn from(io_error: std::io::Error) -> ServiceError { ServiceError::Io(io_error) }
+}
+
+impl std::convert::From<nanoipc::SocketError> for ServiceError {
+	fn from(socket_error: nanoipc::SocketError) -> ServiceError { ServiceError::Socket(socket_error) }
+}
+
+pub fn blocks_service_url(db_path: &str) -> Result<String, std::io::Error> {
+	let mut path = PathBuf::from(db_path);
+	try!(::std::fs::create_dir_all(db_path));
+	path.push("blocks.ipc");
+	Ok(format!("ipc://{}", path.to_str().unwrap()))
+}
+
+pub fn extras_service_url(db_path: &str) -> Result<String, ::std::io::Error> {
+	let mut path = PathBuf::from(db_path);
+	try!(::std::fs::create_dir_all(db_path));
+	path.push("extras.ipc");
+	Ok(format!("ipc://{}", path.to_str().unwrap()))
+}
+
+pub fn blocks_client(db_path: &str) -> Result<DatabaseConnection, ServiceError> {
+	let url = try!(blocks_service_url(db_path));
+	let client = try!(nanoipc::init_client::<DatabaseClient<_>>(&url));
+	Ok(client)
+}
+
+pub fn extras_client(db_path: &str) -> Result<DatabaseConnection, ServiceError> {
+	let url = try!(extras_service_url(db_path));
+	let client = try!(nanoipc::init_client::<DatabaseClient<_>>(&url));
+	Ok(client)
+}
+
+// for tests
+pub fn run_worker(scope: &crossbeam::Scope, stop: Arc<AtomicBool>, socket_path: &str) {
+	let socket_path = socket_path.to_owned();
+	scope.spawn(move || {
+		let mut worker = nanoipc::Worker::new(&Arc::new(Database::new()));
+		worker.add_reqrep(&socket_path).unwrap();
+		while !stop.load(Ordering::Relaxed) {
+			worker.poll();
+		}
+	});
+}
diff --git a/db/src/service.rs b/db/src/service.rs
deleted file mode 100644
index e69de29bb..000000000
diff --git a/db/src/traits.rs b/db/src/traits.rs
index 1e5b2acf4..dd5743fe5 100644
--- a/db/src/traits.rs
+++ b/db/src/traits.rs
@@ -1,21 +1,38 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
 //! Ethcore database trait
 
-use ipc::BinaryConvertable;
 use std::mem;
 use ipc::binary::BinaryConvertError;
 use std::collections::VecDeque;
+use std::cell::RefCell;
 
-pub type TransactionHandle = u32;
 pub type IteratorHandle = u32;
 
+pub const DEFAULT_CACHE_LEN: usize = 12288;
+
 #[derive(Binary)]
 pub struct KeyValue {
 	pub key: Vec<u8>,
 	pub value: Vec<u8>,
 }
 
-#[derive(Debug, Binary)]
-pub enum Error {
+	#[derive(Debug, Binary)]
+	pub enum Error {
 	AlreadyOpen,
 	IsClosed,
 	RocksDb(String),
@@ -28,13 +45,36 @@ pub enum Error {
 #[derive(Binary)]
 pub struct DatabaseConfig {
 	/// Optional prefix size in bytes. Allows lookup by partial key.
-	pub prefix_size: Option<usize>
+	pub prefix_size: Option<usize>,
+	/// write cache length
+	pub cache: usize,
 }
 
-pub trait DatabaseService {
+impl Default for DatabaseConfig {
+	fn default() -> DatabaseConfig {
+		DatabaseConfig {
+			prefix_size: None,
+			cache: DEFAULT_CACHE_LEN,
+		}
+	}
+}
+
+impl DatabaseConfig {
+	fn with_prefix(prefix: usize) -> DatabaseConfig {
+		DatabaseConfig {
+			prefix_size: Some(prefix),
+			cache: DEFAULT_CACHE_LEN,
+		}
+	}
+}
+
+	pub trait DatabaseService : Sized {
 	/// Opens database in the specified path
 	fn open(&self, config: DatabaseConfig, path: String) -> Result<(), Error>;
 
+	/// Opens database in the specified path with the default config
+	fn open_default(&self, path: String) -> Result<(), Error>;
+
 	/// Closes database
 	fn close(&self) -> Result<(), Error>;
 
@@ -44,18 +84,6 @@ pub trait DatabaseService {
 	/// Delete value by key.
 	fn delete(&self, key: &[u8]) -> Result<(), Error>;
 
-	/// Insert a key-value pair in the transaction. Any existing value value will be overwritten.
-	fn transaction_put(&self, transaction: TransactionHandle, key: &[u8], value: &[u8]) -> Result<(), Error>;
-
-	/// Delete value by key using transaction
-	fn transaction_delete(&self, transaction: TransactionHandle, key: &[u8]) -> Result<(), Error>;
-
-	/// Commit transaction to database.
-	fn write(&self, tr: TransactionHandle) -> Result<(), Error>;
-
-	/// Initiate new transaction on database
-	fn new_transaction(&self) -> TransactionHandle;
-
 	/// Get value by key.
 	fn get(&self, key: &[u8]) -> Result<Option<Vec<u8>>, Error>;
 
@@ -70,4 +98,35 @@ pub trait DatabaseService {
 
 	/// Next key-value for the the given iterator
 	fn iter_next(&self, iterator: IteratorHandle) -> Option<KeyValue>;
+
+	/// Dispose iteration that is no longer needed
+	fn dispose_iter(&self, handle: IteratorHandle) -> Result<(), Error>;
+
+	/// Write client transaction
+	fn write(&self, transaction: DBTransaction) -> Result<(), Error>;
+}
+
+#[derive(Binary)]
+pub struct DBTransaction {
+	pub writes: RefCell<Vec<KeyValue>>,
+	pub removes: RefCell<Vec<Vec<u8>>>,
+}
+
+impl DBTransaction {
+	pub fn new() -> DBTransaction {
+		DBTransaction {
+			writes: RefCell::new(Vec::new()),
+			removes: RefCell::new(Vec::new()),
+		}
+	}
+
+	pub fn put(&self, key: &[u8], value: &[u8]) {
+		let mut brw = self.writes.borrow_mut();
+		brw.push(KeyValue { key: key.to_vec(), value: value.to_vec() });
+	}
+
+	pub fn delete(&self, key: &[u8]) {
+		let mut brw = self.removes.borrow_mut();
+		brw.push(key.to_vec());
+	}
 }
diff --git a/ethcore/src/account.rs b/ethcore/src/account.rs
index 66cceda42..7ba213393 100644
--- a/ethcore/src/account.rs
+++ b/ethcore/src/account.rs
@@ -261,7 +261,7 @@ mod tests {
 		let mut db = MemoryDB::new();
 		let mut db = AccountDBMut::new(&mut db, &Address::new());
 		let rlp = {
-			let mut a = Account::new_contract(x!(69), x!(0));
+			let mut a = Account::new_contract(69.into(), 0.into());
 			a.set_storage(H256::from(&U256::from(0x00u64)), H256::from(&U256::from(0x1234u64)));
 			a.commit_storage(&mut db);
 			a.init_code(vec![]);
@@ -281,7 +281,7 @@ mod tests {
 		let mut db = AccountDBMut::new(&mut db, &Address::new());
 
 		let rlp = {
-			let mut a = Account::new_contract(x!(69), x!(0));
+			let mut a = Account::new_contract(69.into(), 0.into());
 			a.init_code(vec![0x55, 0x44, 0xffu8]);
 			a.commit_code(&mut db);
 			a.rlp()
@@ -296,10 +296,10 @@ mod tests {
 
 	#[test]
 	fn commit_storage() {
-		let mut a = Account::new_contract(x!(69), x!(0));
+		let mut a = Account::new_contract(69.into(), 0.into());
 		let mut db = MemoryDB::new();
 		let mut db = AccountDBMut::new(&mut db, &Address::new());
-		a.set_storage(x!(0), x!(0x1234));
+		a.set_storage(0.into(), 0x1234.into());
 		assert_eq!(a.storage_root(), None);
 		a.commit_storage(&mut db);
 		assert_eq!(a.storage_root().unwrap().hex(), "c57e1afb758b07f8d2c8f13a3b6e44fa5ff94ab266facc5a4fd3f062426e50b2");
@@ -307,21 +307,21 @@ mod tests {
 
 	#[test]
 	fn commit_remove_commit_storage() {
-		let mut a = Account::new_contract(x!(69), x!(0));
+		let mut a = Account::new_contract(69.into(), 0.into());
 		let mut db = MemoryDB::new();
 		let mut db = AccountDBMut::new(&mut db, &Address::new());
-		a.set_storage(x!(0), x!(0x1234));
+		a.set_storage(0.into(), 0x1234.into());
 		a.commit_storage(&mut db);
-		a.set_storage(x!(1), x!(0x1234));
+		a.set_storage(1.into(), 0x1234.into());
 		a.commit_storage(&mut db);
-		a.set_storage(x!(1), x!(0));
+		a.set_storage(1.into(), 0.into());
 		a.commit_storage(&mut db);
 		assert_eq!(a.storage_root().unwrap().hex(), "c57e1afb758b07f8d2c8f13a3b6e44fa5ff94ab266facc5a4fd3f062426e50b2");
 	}
 
 	#[test]
 	fn commit_code() {
-		let mut a = Account::new_contract(x!(69), x!(0));
+		let mut a = Account::new_contract(69.into(), 0.into());
 		let mut db = MemoryDB::new();
 		let mut db = AccountDBMut::new(&mut db, &Address::new());
 		a.init_code(vec![0x55, 0x44, 0xffu8]);
diff --git a/ethcore/src/account_db.rs b/ethcore/src/account_db.rs
index f95ec53a1..c21ea2993 100644
--- a/ethcore/src/account_db.rs
+++ b/ethcore/src/account_db.rs
@@ -20,7 +20,7 @@ impl<'db> AccountDB<'db> {
 	pub fn new(db: &'db HashDB, address: &Address) -> AccountDB<'db> {
 		AccountDB {
 			db: db,
-			address: x!(address),
+			address: address.into(),
 		}
 	}
 }
@@ -67,7 +67,7 @@ impl<'db> AccountDBMut<'db> {
 	pub fn new(db: &'db mut HashDB, address: &Address) -> AccountDBMut<'db> {
 		AccountDBMut {
 			db: db,
-			address: x!(address),
+			address: address.into(),
 		}
 	}
 
diff --git a/ethcore/src/basic_authority.rs b/ethcore/src/basic_authority.rs
index fec23cf54..b4a938642 100644
--- a/ethcore/src/basic_authority.rs
+++ b/ethcore/src/basic_authority.rs
@@ -86,9 +86,9 @@ impl Engine for BasicAuthority {
 			let gas_limit = parent.gas_limit;
 			let bound_divisor = self.our_params.gas_limit_bound_divisor;
 			if gas_limit < gas_floor_target {
-				min(gas_floor_target, gas_limit + gas_limit / bound_divisor - x!(1))
+				min(gas_floor_target, gas_limit + gas_limit / bound_divisor - 1.into())
 			} else {
-				max(gas_floor_target, gas_limit - gas_limit / bound_divisor + x!(1))
+				max(gas_floor_target, gas_limit - gas_limit / bound_divisor + 1.into())
 			}
 		};
 		header.note_dirty();
@@ -211,12 +211,12 @@ mod tests {
 		let engine = new_test_authority().engine;
 		let schedule = engine.schedule(&EnvInfo {
 			number: 10000000,
-			author: x!(0),
+			author: 0.into(),
 			timestamp: 0,
-			difficulty: x!(0),
+			difficulty: 0.into(),
 			last_hashes: vec![],
-			gas_used: x!(0),
-			gas_limit: x!(0)
+			gas_used: 0.into(),
+			gas_limit: 0.into()
 		});
 
 		assert!(schedule.stack_limit > 0);
@@ -278,7 +278,7 @@ mod tests {
 		spec.ensure_db_good(db.as_hashdb_mut());
 		let last_hashes = vec![genesis_header.hash()];
 		let vm_factory = Default::default();
-		let b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, last_hashes, addr.clone(), x!(3141562), vec![]);
+		let b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, last_hashes, addr.clone(), 3141562.into(), vec![]);
 		let b = b.close_and_lock();
 		let seal = engine.generate_seal(b.block(), Some(&tap)).unwrap();
 
diff --git a/ethcore/src/block.rs b/ethcore/src/block.rs
index 90d4eec2d..0b75f5a7e 100644
--- a/ethcore/src/block.rs
+++ b/ethcore/src/block.rs
@@ -469,7 +469,7 @@ pub fn enact(header: &Header, transactions: &[SignedTransaction], uncles: &[Head
 		}
 	}
 
-	let mut b = OpenBlock::new(engine, vm_factory, tracing, db, parent, last_hashes, header.author().clone(), x!(3141562), header.extra_data().clone());
+	let mut b = OpenBlock::new(engine, vm_factory, tracing, db, parent, last_hashes, header.author().clone(), 3141562.into(), header.extra_data().clone());
 	b.set_difficulty(*header.difficulty());
 	b.set_gas_limit(*header.gas_limit());
 	b.set_timestamp(header.timestamp());
@@ -514,7 +514,7 @@ mod tests {
 		spec.ensure_db_good(db.as_hashdb_mut());
 		let last_hashes = vec![genesis_header.hash()];
 		let vm_factory = Default::default();
-		let b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, last_hashes, Address::zero(), x!(3141562), vec![]);
+		let b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, last_hashes, Address::zero(), 3141562.into(), vec![]);
 		let b = b.close_and_lock();
 		let _ = b.seal(engine.deref(), vec![]);
 	}
@@ -530,7 +530,7 @@ mod tests {
 		let mut db = db_result.take();
 		spec.ensure_db_good(db.as_hashdb_mut());
 		let vm_factory = Default::default();
-		let b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, vec![genesis_header.hash()], Address::zero(), x!(3141562), vec![]).close_and_lock().seal(engine.deref(), vec![]).unwrap();
+		let b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, vec![genesis_header.hash()], Address::zero(), 3141562.into(), vec![]).close_and_lock().seal(engine.deref(), vec![]).unwrap();
 		let orig_bytes = b.rlp_bytes();
 		let orig_db = b.drain();
 
@@ -557,7 +557,7 @@ mod tests {
 		let mut db = db_result.take();
 		spec.ensure_db_good(db.as_hashdb_mut());
 		let vm_factory = Default::default();
-		let mut open_block = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, vec![genesis_header.hash()], Address::zero(), x!(3141562), vec![]);
+		let mut open_block = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, vec![genesis_header.hash()], Address::zero(), 3141562.into(), vec![]);
 		let mut uncle1_header = Header::new();
 		uncle1_header.extra_data = b"uncle1".to_vec();
 		let mut uncle2_header = Header::new();
diff --git a/ethcore/src/block_queue.rs b/ethcore/src/block_queue.rs
index bf11f5f1f..5e89641c0 100644
--- a/ethcore/src/block_queue.rs
+++ b/ethcore/src/block_queue.rs
@@ -311,17 +311,17 @@ impl BlockQueue {
 		let h = header.hash();
 		{
 			if self.processing.read().unwrap().contains(&h) {
-				return Err(x!(ImportError::AlreadyQueued));
+				return Err(ImportError::AlreadyQueued.into());
 			}
 
 			let mut bad = self.verification.bad.lock().unwrap();
 			if bad.contains(&h) {
-				return Err(x!(ImportError::KnownBad));
+				return Err(ImportError::KnownBad.into());
 			}
 
 			if bad.contains(&header.parent_hash) {
 				bad.insert(h.clone());
-				return Err(x!(ImportError::KnownBad));
+				return Err(ImportError::KnownBad.into());
 			}
 		}
 
diff --git a/ethcore/src/client/client.rs b/ethcore/src/client/client.rs
index ab1c21af1..8fb0de9eb 100644
--- a/ethcore/src/client/client.rs
+++ b/ethcore/src/client/client.rs
@@ -655,10 +655,10 @@ impl<V> BlockChainClient for Client<V> where V: Verifier {
 		{
 			let header = BlockView::new(&bytes).header_view();
 			if self.chain.is_known(&header.sha3()) {
-				return Err(x!(ImportError::AlreadyInChain));
+				return Err(ImportError::AlreadyInChain.into());
 			}
 			if self.block_status(BlockID::Hash(header.parent_hash())) == BlockStatus::Unknown {
-				return Err(x!(BlockError::UnknownParent(header.parent_hash())));
+				return Err(BlockError::UnknownParent(header.parent_hash()).into());
 			}
 		}
 		self.block_queue.import_block(bytes)
diff --git a/ethcore/src/env_info.rs b/ethcore/src/env_info.rs
index 18b8af856..e6d15cee6 100644
--- a/ethcore/src/env_info.rs
+++ b/ethcore/src/env_info.rs
@@ -47,10 +47,10 @@ impl Default for EnvInfo {
 			number: 0,
 			author: Address::new(),
 			timestamp: 0,
-			difficulty: x!(0),
-			gas_limit: x!(0),
+			difficulty: 0.into(),
+			gas_limit: 0.into(),
 			last_hashes: vec![],
-			gas_used: x!(0),
+			gas_used: 0.into(),
 		}
 	}
 }
@@ -92,15 +92,15 @@ mod tests {
 
 		assert_eq!(env_info.number, 1112339);
 		assert_eq!(env_info.author, Address::from_str("000000f00000000f000000000000f00000000f00").unwrap());
-		assert_eq!(env_info.gas_limit, x!(40000));
-		assert_eq!(env_info.difficulty, x!(50000));
-		assert_eq!(env_info.gas_used, x!(0));
+		assert_eq!(env_info.gas_limit, 40000.into());
+		assert_eq!(env_info.difficulty, 50000.into());
+		assert_eq!(env_info.gas_used, 0.into());
 	}
 
 	#[test]
 	fn it_can_be_created_as_default() {
 		let default_env_info = EnvInfo::default();
 
-		assert_eq!(default_env_info.difficulty, x!(0));
+		assert_eq!(default_env_info.difficulty, 0.into());
 	}
 }
diff --git a/ethcore/src/ethereum/ethash.rs b/ethcore/src/ethereum/ethash.rs
index cb06959d0..1dadb8a65 100644
--- a/ethcore/src/ethereum/ethash.rs
+++ b/ethcore/src/ethereum/ethash.rs
@@ -111,9 +111,9 @@ impl Engine for Ethash {
 			let gas_limit = parent.gas_limit;
 			let bound_divisor = self.ethash_params.gas_limit_bound_divisor;
 			if gas_limit < gas_floor_target {
-				min(gas_floor_target, gas_limit + gas_limit / bound_divisor - x!(1))
+				min(gas_floor_target, gas_limit + gas_limit / bound_divisor - 1.into())
 			} else {
-				max(gas_floor_target, gas_limit - gas_limit / bound_divisor + x!(1) + (header.gas_used * x!(6) / x!(5)) / bound_divisor)
+				max(gas_floor_target, gas_limit - gas_limit / bound_divisor + 1.into() + (header.gas_used * 6.into() / 5.into()) / bound_divisor)
 			}
 		};
 		header.note_dirty();
@@ -255,12 +255,12 @@ impl Ethash {
 
 	/// Convert an Ethash boundary to its original difficulty. Basically just `f(x) = 2^256 / x`.
 	pub fn boundary_to_difficulty(boundary: &H256) -> U256 {
-		U256::from((U512::one() << 256) / x!(U256::from(boundary.as_slice())))
+		U256::from((U512::one() << 256) / U256::from(boundary.as_slice()).into())
 	}
 
 	/// Convert an Ethash difficulty to the target boundary. Basically just `f(x) = 2^256 / x`.
 	pub fn difficulty_to_boundary(difficulty: &U256) -> H256 {
-		x!(U256::from((U512::one() << 256) / x!(difficulty)))
+		U256::from((U512::one() << 256) / difficulty.into()).into()
 	}
 
 	fn to_ethash(hash: H256) -> EH256 {
@@ -308,7 +308,7 @@ mod tests {
 		spec.ensure_db_good(db.as_hashdb_mut());
 		let last_hashes = vec![genesis_header.hash()];
 		let vm_factory = Default::default();
-		let b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, last_hashes, Address::zero(), x!(3141562), vec![]);
+		let b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, last_hashes, Address::zero(), 3141562.into(), vec![]);
 		let b = b.close();
 		assert_eq!(b.state().balance(&Address::zero()), U256::from_str("4563918244f40000").unwrap());
 	}
@@ -323,7 +323,7 @@ mod tests {
 		spec.ensure_db_good(db.as_hashdb_mut());
 		let last_hashes = vec![genesis_header.hash()];
 		let vm_factory = Default::default();
-		let mut b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, last_hashes, Address::zero(), x!(3141562), vec![]);
+		let mut b = OpenBlock::new(engine.deref(), &vm_factory, false, db, &genesis_header, last_hashes, Address::zero(), 3141562.into(), vec![]);
 		let mut uncle = Header::new();
 		let uncle_author = address_from_hex("ef2d6d194084c2de36e0dabfce45d046b37d1106");
 		uncle.author = uncle_author.clone();
@@ -346,24 +346,24 @@ mod tests {
 		let engine = new_morden().engine;
 		let schedule = engine.schedule(&EnvInfo {
 			number: 10000000,
-			author: x!(0),
+			author: 0.into(),
 			timestamp: 0,
-			difficulty: x!(0),
+			difficulty: 0.into(),
 			last_hashes: vec![],
-			gas_used: x!(0),
-			gas_limit: x!(0)
+			gas_used: 0.into(),
+			gas_limit: 0.into()
 		});
 
 		assert!(schedule.stack_limit > 0);
 
 		let schedule = engine.schedule(&EnvInfo {
 			number: 100,
-			author: x!(0),
+			author: 0.into(),
 			timestamp: 0,
-			difficulty: x!(0),
+			difficulty: 0.into(),
 			last_hashes: vec![],
-			gas_used: x!(0),
-			gas_limit: x!(0)
+			gas_used: 0.into(),
+			gas_limit: 0.into()
 		});
 
 		assert!(!schedule.have_delegate_call);
diff --git a/ethcore/src/executive.rs b/ethcore/src/executive.rs
index 320a89cb8..291b4dba2 100644
--- a/ethcore/src/executive.rs
+++ b/ethcore/src/executive.rs
@@ -361,7 +361,7 @@ impl<'a> Executive<'a> {
 		let refunds_bound = sstore_refunds + suicide_refunds;
 
 		// real ammount to refund
-		let gas_left_prerefund = match result { Ok(x) => x, _ => x!(0) };
+		let gas_left_prerefund = match result { Ok(x) => x, _ => 0.into() };
 		let refunded = cmp::min(refunds_bound, (t.gas - gas_left_prerefund) / U256::from(2));
 		let gas_left = gas_left_prerefund + refunded;
 
@@ -588,10 +588,10 @@ mod tests {
 		let expected_trace = vec![ Trace {
 			depth: 0,
 			action: trace::Action::Call(trace::Call {
-				from: x!("cd1722f3947def4cf144679da39c4c32bdc35681"),
-				to: x!("b010143a42d5980c7e5ef0e4a4416dc098a4fed3"),
-				value: x!(100),
-				gas: x!(100000),
+				from: "cd1722f3947def4cf144679da39c4c32bdc35681".into(),
+				to: "b010143a42d5980c7e5ef0e4a4416dc098a4fed3".into(),
+				value: 100.into(),
+				gas: 100000.into(),
 				input: vec![],
 			}),
 			result: trace::Res::Call(trace::CallResult {
@@ -601,9 +601,9 @@ mod tests {
 			subs: vec![Trace {
 				depth: 1,
 				action: trace::Action::Create(trace::Create {
-					from: x!("b010143a42d5980c7e5ef0e4a4416dc098a4fed3"),
-					value: x!(23),
-					gas: x!(67979),
+					from: "b010143a42d5980c7e5ef0e4a4416dc098a4fed3".into(),
+					value: 23.into(),
+					gas: 67979.into(),
 					init: 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]
 				}),
 				result: trace::Res::Create(trace::CreateResult {
@@ -642,7 +642,7 @@ mod tests {
 		params.origin = sender.clone();
 		params.gas = U256::from(100_000);
 		params.code = Some(code.clone());
-		params.value = ActionValue::Transfer(x!(100));
+		params.value = ActionValue::Transfer(100.into());
 		let mut state_result = get_temp_state();
 		let mut state = state_result.reference_mut();
 		state.add_balance(&sender, &U256::from(100));
@@ -660,7 +660,7 @@ mod tests {
 			depth: 0,
 			action: trace::Action::Create(trace::Create {
 				from: params.sender,
-				value: x!(100),
+				value: 100.into(),
 				gas: params.gas,
 				init: 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],
 			}),
diff --git a/ethcore/src/externalities.rs b/ethcore/src/externalities.rs
index c936ac207..99d2eed72 100644
--- a/ethcore/src/externalities.rs
+++ b/ethcore/src/externalities.rs
@@ -311,12 +311,12 @@ mod tests {
 	fn get_test_env_info() -> EnvInfo {
 		EnvInfo {
 			number: 100,
-			author: x!(0),
+			author: 0.into(),
 			timestamp: 0,
-			difficulty: x!(0),
+			difficulty: 0.into(),
 			last_hashes: vec![],
-			gas_used: x!(0),
-			gas_limit: x!(0)
+			gas_used: 0.into(),
+			gas_limit: 0.into()
 		}
 	}
 
diff --git a/ethcore/src/pod_account.rs b/ethcore/src/pod_account.rs
index 27ddc8a97..65146296a 100644
--- a/ethcore/src/pod_account.rs
+++ b/ethcore/src/pod_account.rs
@@ -114,11 +114,11 @@ mod test {
 
 	#[test]
 	fn existence() {
-		let a = PodAccount{balance: x!(69), nonce: x!(0), code: vec![], storage: map![]};
+		let a = PodAccount{balance: 69.into(), nonce: 0.into(), code: vec![], storage: map![]};
 		assert_eq!(AccountDiff::diff_pod(Some(&a), Some(&a)), None);
 		assert_eq!(AccountDiff::diff_pod(None, Some(&a)), Some(AccountDiff{
-			balance: Diff::Born(x!(69)),
-			nonce: Diff::Born(x!(0)),
+			balance: Diff::Born(69.into()),
+			nonce: Diff::Born(0.into()),
 			code: Diff::Born(vec![]),
 			storage: map![],
 		}));
@@ -126,11 +126,11 @@ mod test {
 
 	#[test]
 	fn basic() {
-		let a = PodAccount{balance: x!(69), nonce: x!(0), code: vec![], storage: map![]};
-		let b = PodAccount{balance: x!(42), nonce: x!(1), code: vec![], storage: map![]};
+		let a = PodAccount{balance: 69.into(), nonce: 0.into(), code: vec![], storage: map![]};
+		let b = PodAccount{balance: 42.into(), nonce: 1.into(), code: vec![], storage: map![]};
 		assert_eq!(AccountDiff::diff_pod(Some(&a), Some(&b)), Some(AccountDiff {
-			balance: Diff::Changed(x!(69), x!(42)),
-			nonce: Diff::Changed(x!(0), x!(1)),
+			balance: Diff::Changed(69.into(), 42.into()),
+			nonce: Diff::Changed(0.into(), 1.into()),
 			code: Diff::Same,
 			storage: map![],
 		}));
@@ -138,11 +138,11 @@ mod test {
 
 	#[test]
 	fn code() {
-		let a = PodAccount{balance: x!(0), nonce: x!(0), code: vec![], storage: map![]};
-		let b = PodAccount{balance: x!(0), nonce: x!(1), code: vec![0], storage: map![]};
+		let a = PodAccount{balance: 0.into(), nonce: 0.into(), code: vec![], storage: map![]};
+		let b = PodAccount{balance: 0.into(), nonce: 1.into(), code: vec![0], storage: map![]};
 		assert_eq!(AccountDiff::diff_pod(Some(&a), Some(&b)), Some(AccountDiff {
 			balance: Diff::Same,
-			nonce: Diff::Changed(x!(0), x!(1)),
+			nonce: Diff::Changed(0.into(), 1.into()),
 			code: Diff::Changed(vec![], vec![0]),
 			storage: map![],
 		}));
@@ -151,27 +151,27 @@ mod test {
 	#[test]
 	fn storage() {
 		let a = PodAccount {
-			balance: x!(0),
-			nonce: x!(0),
+			balance: 0.into(),
+			nonce: 0.into(),
 			code: vec![],
-			storage: mapx![1 => 1, 2 => 2, 3 => 3, 4 => 4, 5 => 0, 6 => 0, 7 => 0]
+			storage: map_into![1 => 1, 2 => 2, 3 => 3, 4 => 4, 5 => 0, 6 => 0, 7 => 0]
 		};
 		let b = PodAccount {
-			balance: x!(0),
-			nonce: x!(0),
+			balance: 0.into(),
+			nonce: 0.into(),
 			code: vec![],
-			storage: mapx![1 => 1, 2 => 3, 3 => 0, 5 => 0, 7 => 7, 8 => 0, 9 => 9]
+			storage: map_into![1 => 1, 2 => 3, 3 => 0, 5 => 0, 7 => 7, 8 => 0, 9 => 9]
 		};
 		assert_eq!(AccountDiff::diff_pod(Some(&a), Some(&b)), Some(AccountDiff {
 			balance: Diff::Same,
 			nonce: Diff::Same,
 			code: Diff::Same,
 			storage: map![
-				x!(2) => Diff::new(x!(2), x!(3)),
-				x!(3) => Diff::new(x!(3), x!(0)),
-				x!(4) => Diff::new(x!(4), x!(0)),
-				x!(7) => Diff::new(x!(0), x!(7)),
-				x!(9) => Diff::new(x!(0), x!(9))
+				2.into() => Diff::new(2.into(), 3.into()),
+				3.into() => Diff::new(3.into(), 0.into()),
+				4.into() => Diff::new(4.into(), 0.into()),
+				7.into() => Diff::new(0.into(), 7.into()),
+				9.into() => Diff::new(0.into(), 9.into())
 			],
 		}));
 	}
diff --git a/ethcore/src/state.rs b/ethcore/src/state.rs
index eabca24a8..c099b17a5 100644
--- a/ethcore/src/state.rs
+++ b/ethcore/src/state.rs
@@ -214,7 +214,7 @@ impl State {
 	/// Initialise the code of account `a` so that it is `value` for `key`.
 	/// NOTE: Account should have been created with `new_contract`.
 	pub fn init_code(&mut self, a: &Address, code: Bytes) {
-		self.require_or_from(a, true, || Account::new_contract(x!(0), self.account_start_nonce), |_|{}).init_code(code);
+		self.require_or_from(a, true, || Account::new_contract(0.into(), self.account_start_nonce), |_|{}).init_code(code);
 	}
 
 	/// Execute a given transaction.
@@ -377,27 +377,27 @@ fn should_apply_create_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
 		action: Action::Create,
-		value: x!(100),
+		value: 100.into(),
 		data: FromHex::from_hex("601080600c6000396000f3006000355415600957005b60203560003555").unwrap(),
 	}.sign(&"".sha3());
 
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Create(trace::Create {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			value: x!(100),
-			gas: x!(77412),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			value: 100.into(),
+			gas: 77412.into(),
 			init: 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],
 		}),
 		result: trace::Res::Create(trace::CreateResult {
@@ -438,27 +438,27 @@ fn should_trace_failed_create_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
 		action: Action::Create,
-		value: x!(100),
+		value: 100.into(),
 		data: FromHex::from_hex("5b600056").unwrap(),
 	}.sign(&"".sha3());
 
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Create(trace::Create {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			value: x!(100),
-			gas: x!(78792),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			value: 100.into(),
+			gas: 78792.into(),
 			init: vec![91, 96, 0, 86],
 		}),
 		result: trace::Res::FailedCreate,
@@ -476,29 +476,29 @@ fn should_trace_call_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("6000").unwrap());
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.init_code(&0xa.into(), FromHex::from_hex("6000").unwrap());
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -519,28 +519,28 @@ fn should_trace_basic_call_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -561,15 +561,15 @@ fn should_trace_call_transaction_to_builtin() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = Spec::new_test().engine;
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0x1)),
-		value: x!(0),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0x1.into()),
+		value: 0.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
@@ -579,10 +579,10 @@ fn should_trace_call_transaction_to_builtin() {
 	assert_eq!(result.trace, Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!("0000000000000000000000000000000000000001"),
-			value: x!(0),
-			gas: x!(79_000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: "0000000000000000000000000000000000000001".into(),
+			value: 0.into(),
+			gas: 79_000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -601,29 +601,29 @@ fn should_not_trace_subcall_transaction_to_builtin() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = Spec::new_test().engine;
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(0),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 0.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("600060006000600060006001610be0f1").unwrap());
+	state.init_code(&0xa.into(), FromHex::from_hex("600060006000600060006001610be0f1").unwrap());
 	let vm_factory = Default::default();
 	let result = state.apply(&info, engine.deref(), &vm_factory, &t, true).unwrap();
 
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(0),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 0.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -643,30 +643,30 @@ fn should_not_trace_callcode() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = Spec::new_test().engine;
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(0),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 0.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("60006000600060006000600b611000f2").unwrap());
-	state.init_code(&x!(0xb), FromHex::from_hex("6000").unwrap());
+	state.init_code(&0xa.into(), FromHex::from_hex("60006000600060006000600b611000f2").unwrap());
+	state.init_code(&0xb.into(), FromHex::from_hex("6000").unwrap());
 	let vm_factory = Default::default();
 	let result = state.apply(&info, engine.deref(), &vm_factory, &t, true).unwrap();
 
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(0),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 0.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -686,33 +686,33 @@ fn should_not_trace_delegatecall() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	info.number = 0x789b0;
 	let engine = Spec::new_test().engine;
 
 	println!("schedule.have_delegate_call: {:?}", engine.schedule(&info).have_delegate_call);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(0),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 0.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("6000600060006000600b618000f4").unwrap());
-	state.init_code(&x!(0xb), FromHex::from_hex("6000").unwrap());
+	state.init_code(&0xa.into(), FromHex::from_hex("6000600060006000600b618000f4").unwrap());
+	state.init_code(&0xb.into(), FromHex::from_hex("6000").unwrap());
 	let vm_factory = Default::default();
 	let result = state.apply(&info, engine.deref(), &vm_factory, &t, true).unwrap();
 
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(0),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 0.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -732,29 +732,29 @@ fn should_trace_failed_call_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("5b600056").unwrap());
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.init_code(&0xa.into(), FromHex::from_hex("5b600056").unwrap());
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::FailedCall,
@@ -774,30 +774,30 @@ fn should_trace_call_with_subcall_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("60006000600060006000600b602b5a03f1").unwrap());
-	state.init_code(&x!(0xb), FromHex::from_hex("6000").unwrap());
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.init_code(&0xa.into(), FromHex::from_hex("60006000600060006000600b602b5a03f1").unwrap());
+	state.init_code(&0xb.into(), FromHex::from_hex("6000").unwrap());
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -807,10 +807,10 @@ fn should_trace_call_with_subcall_transaction() {
 		subs: vec![Trace {
 			depth: 1,
 			action: trace::Action::Call(trace::Call {
-				from: x!(0xa),
-				to: x!(0xb),
-				value: x!(0),
-				gas: x!(78934),
+				from: 0xa.into(),
+				to: 0xb.into(),
+				value: 0.into(),
+				gas: 78934.into(),
 				input: vec![],
 			}),
 			result: trace::Res::Call(trace::CallResult {
@@ -832,29 +832,29 @@ fn should_trace_call_with_basic_subcall_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("60006000600060006045600b6000f1").unwrap());
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.init_code(&0xa.into(), FromHex::from_hex("60006000600060006045600b6000f1").unwrap());
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -864,10 +864,10 @@ fn should_trace_call_with_basic_subcall_transaction() {
 		subs: vec![Trace {
 			depth: 1,
 			action: trace::Action::Call(trace::Call {
-				from: x!(0xa),
-				to: x!(0xb),
-				value: x!(69),
-				gas: x!(2300),
+				from: 0xa.into(),
+				to: 0xb.into(),
+				value: 69.into(),
+				gas: 2300.into(),
 				input: vec![],
 			}),
 			result: trace::Res::Call(trace::CallResult::default()),
@@ -886,29 +886,29 @@ fn should_not_trace_call_with_invalid_basic_subcall_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("600060006000600060ff600b6000f1").unwrap());	// not enough funds.
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.init_code(&0xa.into(), FromHex::from_hex("600060006000600060ff600b6000f1").unwrap());	// not enough funds.
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -929,30 +929,30 @@ fn should_trace_failed_subcall_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],//600480600b6000396000f35b600056
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("60006000600060006000600b602b5a03f1").unwrap());
-	state.init_code(&x!(0xb), FromHex::from_hex("5b600056").unwrap());
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.init_code(&0xa.into(), FromHex::from_hex("60006000600060006000600b602b5a03f1").unwrap());
+	state.init_code(&0xb.into(), FromHex::from_hex("5b600056").unwrap());
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -962,10 +962,10 @@ fn should_trace_failed_subcall_transaction() {
 		subs: vec![Trace {
 			depth: 1,
 			action: trace::Action::Call(trace::Call {
-				from: x!(0xa),
-				to: x!(0xb),
-				value: x!(0),
-				gas: x!(78934),
+				from: 0xa.into(),
+				to: 0xb.into(),
+				value: 0.into(),
+				gas: 78934.into(),
 				input: vec![],
 			}),
 			result: trace::Res::FailedCall,
@@ -984,31 +984,31 @@ fn should_trace_call_with_subcall_with_subcall_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("60006000600060006000600b602b5a03f1").unwrap());
-	state.init_code(&x!(0xb), FromHex::from_hex("60006000600060006000600c602b5a03f1").unwrap());
-	state.init_code(&x!(0xc), FromHex::from_hex("6000").unwrap());
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.init_code(&0xa.into(), FromHex::from_hex("60006000600060006000600b602b5a03f1").unwrap());
+	state.init_code(&0xb.into(), FromHex::from_hex("60006000600060006000600c602b5a03f1").unwrap());
+	state.init_code(&0xc.into(), FromHex::from_hex("6000").unwrap());
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -1018,10 +1018,10 @@ fn should_trace_call_with_subcall_with_subcall_transaction() {
 		subs: vec![Trace {
 			depth: 1,
 			action: trace::Action::Call(trace::Call {
-				from: x!(0xa),
-				to: x!(0xb),
-				value: x!(0),
-				gas: x!(78934),
+				from: 0xa.into(),
+				to: 0xb.into(),
+				value: 0.into(),
+				gas: 78934.into(),
 				input: vec![],
 			}),
 			result: trace::Res::Call(trace::CallResult {
@@ -1031,10 +1031,10 @@ fn should_trace_call_with_subcall_with_subcall_transaction() {
 			subs: vec![Trace {
 				depth: 2,
 				action: trace::Action::Call(trace::Call {
-					from: x!(0xb),
-					to: x!(0xc),
-					value: x!(0),
-					gas: x!(78868),
+					from: 0xb.into(),
+					to: 0xc.into(),
+					value: 0.into(),
+					gas: 78868.into(),
 					input: vec![],
 				}),
 				result: trace::Res::Call(trace::CallResult {
@@ -1057,31 +1057,31 @@ fn should_trace_failed_subcall_with_subcall_transaction() {
 	let mut state = get_temp_state_in(temp.as_path());
 
 	let mut info = EnvInfo::default();
-	info.gas_limit = x!(1_000_000);
+	info.gas_limit = 1_000_000.into();
 	let engine = TestEngine::new(5);
 
 	let t = Transaction {
-		nonce: x!(0),
-		gas_price: x!(0),
-		gas: x!(100_000),
-		action: Action::Call(x!(0xa)),
-		value: x!(100),
+		nonce: 0.into(),
+		gas_price: 0.into(),
+		gas: 100_000.into(),
+		action: Action::Call(0xa.into()),
+		value: 100.into(),
 		data: vec![],//600480600b6000396000f35b600056
 	}.sign(&"".sha3());
 
-	state.init_code(&x!(0xa), FromHex::from_hex("60006000600060006000600b602b5a03f1").unwrap());
-	state.init_code(&x!(0xb), FromHex::from_hex("60006000600060006000600c602b5a03f1505b601256").unwrap());
-	state.init_code(&x!(0xc), FromHex::from_hex("6000").unwrap());
-	state.add_balance(t.sender().as_ref().unwrap(), &x!(100));
+	state.init_code(&0xa.into(), FromHex::from_hex("60006000600060006000600b602b5a03f1").unwrap());
+	state.init_code(&0xb.into(), FromHex::from_hex("60006000600060006000600c602b5a03f1505b601256").unwrap());
+	state.init_code(&0xc.into(), FromHex::from_hex("6000").unwrap());
+	state.add_balance(t.sender().as_ref().unwrap(), &(100.into()));
 	let vm_factory = Default::default();
 	let result = state.apply(&info, &engine, &vm_factory, &t, true).unwrap();
 	let expected_trace = Some(Trace {
 		depth: 0,
 		action: trace::Action::Call(trace::Call {
-			from: x!("9cce34f7ab185c7aba1b7c8140d620b4bda941d6"),
-			to: x!(0xa),
-			value: x!(100),
-			gas: x!(79000),
+			from: "9cce34f7ab185c7aba1b7c8140d620b4bda941d6".into(),
+			to: 0xa.into(),
+			value: 100.into(),
+			gas: 79000.into(),
 			input: vec![],
 		}),
 		result: trace::Res::Call(trace::CallResult {
@@ -1091,21 +1091,21 @@ fn should_trace_failed_subcall_with_subcall_transaction() {
 		subs: vec![Trace {
 			depth: 1,
 			action: trace::Action::Call(trace::Call {
-				from: x!(0xa),
-				to: x!(0xb),
-				value: x!(0),
-				gas: x!(78934),
+				from: 0xa.into(),
+				to: 0xb.into(),
+				value: 0.into(),
+				gas: 78934.into(),
 				input: vec![],
 			}),
 			result: trace::Res::FailedCall,
 			subs: vec![Trace {
 				depth: 2,
 				action: trace::Action::Call(trace::Call {
-					from: x!(0xb),
-					to: x!(0xc),
-					value: x!(0),
-					gas: x!(78868),
-					input: vec![],
+				from: 0xb.into(),
+				to: 0xc.into(),
+				value: 0.into(),
+				gas: 78868.into(),
+				input: vec![],
 				}),
 				result: trace::Res::Call(trace::CallResult {
 					gas_used: U256::from(3),
@@ -1125,7 +1125,7 @@ fn code_from_database() {
 	let temp = RandomTempPath::new();
 	let (root, db) = {
 		let mut state = get_temp_state_in(temp.as_path());
-		state.require_or_from(&a, false, ||Account::new_contract(x!(42), x!(0)), |_|{});
+		state.require_or_from(&a, false, ||Account::new_contract(42.into(), 0.into()), |_|{});
 		state.init_code(&a, vec![1, 2, 3]);
 		assert_eq!(state.code(&a), Some([1u8, 2, 3].to_vec()));
 		state.commit();
diff --git a/ethcore/src/state_diff.rs b/ethcore/src/state_diff.rs
index 6c41d167c..c362d96d1 100644
--- a/ethcore/src/state_diff.rs
+++ b/ethcore/src/state_diff.rs
@@ -59,19 +59,19 @@ mod test {
 
 	#[test]
 	fn create_delete() {
-		let a = PodState::from(map![ x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]) ]);
+		let a = PodState::from(map![ 1.into() => PodAccount::new(69.into(), 0.into(), vec![], map![]) ]);
 		assert_eq!(StateDiff::diff_pod(&a, &PodState::new()), StateDiff(map![
-			x!(1) => AccountDiff{
-				balance: Diff::Died(x!(69)),
-				nonce: Diff::Died(x!(0)),
+			1.into() => AccountDiff{
+				balance: Diff::Died(69.into()),
+				nonce: Diff::Died(0.into()),
 				code: Diff::Died(vec![]),
 				storage: map![],
 			}
 		]));
 		assert_eq!(StateDiff::diff_pod(&PodState::new(), &a), StateDiff(map![
-			x!(1) => AccountDiff{
-				balance: Diff::Born(x!(69)),
-				nonce: Diff::Born(x!(0)),
+			1.into() => AccountDiff{
+				balance: Diff::Born(69.into()),
+				nonce: Diff::Born(0.into()),
 				code: Diff::Born(vec![]),
 				storage: map![],
 			}
@@ -80,23 +80,23 @@ mod test {
 
 	#[test]
 	fn create_delete_with_unchanged() {
-		let a = PodState::from(map![ x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]) ]);
+		let a = PodState::from(map![ 1.into() => PodAccount::new(69.into(), 0.into(), vec![], map![]) ]);
 		let b = PodState::from(map![
-			x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]),
-			x!(2) => PodAccount::new(x!(69), x!(0), vec![], map![])
+			1.into() => PodAccount::new(69.into(), 0.into(), vec![], map![]),
+			2.into() => PodAccount::new(69.into(), 0.into(), vec![], map![])
 		]);
 		assert_eq!(StateDiff::diff_pod(&a, &b), StateDiff(map![
-			x!(2) => AccountDiff{
-				balance: Diff::Born(x!(69)),
-				nonce: Diff::Born(x!(0)),
+			2.into() => AccountDiff{
+				balance: Diff::Born(69.into()),
+				nonce: Diff::Born(0.into()),
 				code: Diff::Born(vec![]),
 				storage: map![],
 			}
 		]));
 		assert_eq!(StateDiff::diff_pod(&b, &a), StateDiff(map![
-			x!(2) => AccountDiff{
-				balance: Diff::Died(x!(69)),
-				nonce: Diff::Died(x!(0)),
+			2.into() => AccountDiff{
+				balance: Diff::Died(69.into()),
+				nonce: Diff::Died(0.into()),
 				code: Diff::Died(vec![]),
 				storage: map![],
 			}
@@ -106,17 +106,17 @@ mod test {
 	#[test]
 	fn change_with_unchanged() {
 		let a = PodState::from(map![
-			x!(1) => PodAccount::new(x!(69), x!(0), vec![], map![]),
-			x!(2) => PodAccount::new(x!(69), x!(0), vec![], map![])
+			1.into() => PodAccount::new(69.into(), 0.into(), vec![], map![]),
+			2.into() => PodAccount::new(69.into(), 0.into(), vec![], map![])
 		]);
 		let b = PodState::from(map![
-			x!(1) => PodAccount::new(x!(69), x!(1), vec![], map![]),
-			x!(2) => PodAccount::new(x!(69), x!(0), vec![], map![])
+			1.into() => PodAccount::new(69.into(), 1.into(), vec![], map![]),
+			2.into() => PodAccount::new(69.into(), 0.into(), vec![], map![])
 		]);
 		assert_eq!(StateDiff::diff_pod(&a, &b), StateDiff(map![
-			x!(1) => AccountDiff{
+			1.into() => AccountDiff{
 				balance: Diff::Same,
-				nonce: Diff::Changed(x!(0), x!(1)),
+				nonce: Diff::Changed(0.into(), 1.into()),
 				code: Diff::Same,
 				storage: map![],
 			}
diff --git a/ethcore/src/substate.rs b/ethcore/src/substate.rs
index 65b314663..247bbb398 100644
--- a/ethcore/src/substate.rs
+++ b/ethcore/src/substate.rs
@@ -74,7 +74,7 @@ mod tests {
 			topics: vec![],
 			data: vec![]
 		});
-		sub_state.sstore_clears_count = x!(5);
+		sub_state.sstore_clears_count = 5.into();
 		sub_state.suicides.insert(address_from_u64(10u64));
 
 		let mut sub_state_2 = Substate::new();
@@ -84,11 +84,11 @@ mod tests {
 			topics: vec![],
 			data: vec![]
 		});
-		sub_state_2.sstore_clears_count = x!(7);
+		sub_state_2.sstore_clears_count = 7.into();
 
 		sub_state.accrue(sub_state_2);
 		assert_eq!(sub_state.contracts_created.len(), 2);
-		assert_eq!(sub_state.sstore_clears_count, x!(12));
+		assert_eq!(sub_state.sstore_clears_count, 12.into());
 		assert_eq!(sub_state.suicides.len(), 1);
 	}
 }
diff --git a/ethcore/src/tests/client.rs b/ethcore/src/tests/client.rs
index d734b0b47..4a71bf7d7 100644
--- a/ethcore/src/tests/client.rs
+++ b/ethcore/src/tests/client.rs
@@ -136,7 +136,7 @@ fn can_mine() {
 	let client_result = get_test_client_with_blocks(vec![dummy_blocks[0].clone()]);
 	let client = client_result.reference();
 
-	let b = client.prepare_sealing(Address::default(), x!(31415926), vec![], vec![]).0.unwrap();
+	let b = client.prepare_sealing(Address::default(), 31415926.into(), vec![], vec![]).0.unwrap();
 
 	assert_eq!(*b.block().header().parent_hash(), BlockView::new(&dummy_blocks[0]).header_view().sha3());
 	assert!(client.try_seal(b.lock(), vec![]).is_ok());
diff --git a/ethcore/src/tests/helpers.rs b/ethcore/src/tests/helpers.rs
index 7262da9e8..22282ccdd 100644
--- a/ethcore/src/tests/helpers.rs
+++ b/ethcore/src/tests/helpers.rs
@@ -98,8 +98,8 @@ pub fn create_test_block(header: &Header) -> Bytes {
 
 fn create_unverifiable_block_header(order: u32, parent_hash: H256) -> Header {
 	let mut header = Header::new();
-	header.gas_limit = x!(0);
-	header.difficulty = x!(order * 100);
+	header.gas_limit = 0.into();
+	header.difficulty = (order * 100).into();
 	header.timestamp = (order * 10) as u64;
 	header.number = order as u64;
 	header.parent_hash = parent_hash;
@@ -335,7 +335,7 @@ pub fn get_bad_state_dummy_block() -> Bytes {
 	block_header.timestamp = 40;
 	block_header.number = 1;
 	block_header.parent_hash = test_spec.genesis_header().hash();
-	block_header.state_root = x!(0xbad);
+	block_header.state_root = 0xbad.into();
 
 	create_test_block(&block_header)
 }
diff --git a/ethcore/src/types/receipt.rs b/ethcore/src/types/receipt.rs
index f07a12212..78216eb16 100644
--- a/ethcore/src/types/receipt.rs
+++ b/ethcore/src/types/receipt.rs
@@ -105,10 +105,10 @@ pub struct LocalizedReceipt {
 fn test_basic() {
 	let expected = ::rustc_serialize::hex::FromHex::from_hex("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").unwrap();
 	let r = Receipt::new(
-		x!("2f697d671e9ae4ee24a43c4b0d7e15f1cb4ba6de1561120d43b9a4e8c4a8a6ee"),
-		x!(0x40cae),
+		"2f697d671e9ae4ee24a43c4b0d7e15f1cb4ba6de1561120d43b9a4e8c4a8a6ee".into(),
+		0x40cae.into(),
 		vec![LogEntry {
-			address: x!("dcf421d093428b096ca501a7cd1a740855a7976f"),
+			address: "dcf421d093428b096ca501a7cd1a740855a7976f".into(),
 			topics: vec![],
 			data: vec![0u8; 32]
 		}]
diff --git a/miner/src/lib.rs b/miner/src/lib.rs
index a1780efff..f91811948 100644
--- a/miner/src/lib.rs
+++ b/miner/src/lib.rs
@@ -150,10 +150,10 @@ pub trait MinerService : Send + Sync {
 	fn last_nonce(&self, address: &Address) -> Option<U256>;
 
 	/// Suggested gas price.
-	fn sensible_gas_price(&self) -> U256 { x!(20000000000u64) }
+	fn sensible_gas_price(&self) -> U256 { 20000000000u64.into() }
 
 	/// Suggested gas limit.
-	fn sensible_gas_limit(&self) -> U256 { x!(21000) }
+	fn sensible_gas_limit(&self) -> U256 { 21000.into() }
 
 	/// Latest account balance in pending state.
 	fn balance(&self, chain: &BlockChainClient, address: &Address) -> U256;
diff --git a/miner/src/miner.rs b/miner/src/miner.rs
index fc63aec6c..b40fdf7c8 100644
--- a/miner/src/miner.rs
+++ b/miner/src/miner.rs
@@ -18,14 +18,14 @@ use rayon::prelude::*;
 use std::sync::atomic::AtomicBool;
 
 use util::*;
-use util::keys::store::{AccountService, AccountProvider};
+use util::keys::store::AccountProvider;
 use ethcore::views::{BlockView, HeaderView};
 use ethcore::client::{BlockChainClient, BlockID};
 use ethcore::block::{ClosedBlock, IsBlock};
 use ethcore::error::*;
 use ethcore::client::{Executive, Executed, EnvInfo, TransactOptions};
 use ethcore::transaction::SignedTransaction;
-use ethcore::receipt::{Receipt};
+use ethcore::receipt::Receipt;
 use ethcore::spec::Spec;
 use ethcore::engine::Engine;
 use super::{MinerService, MinerStatus, TransactionQueue, AccountDetails, TransactionImportResult, TransactionOrigin};
@@ -44,7 +44,7 @@ pub struct Miner {
 	extra_data: RwLock<Bytes>,
 	spec: Spec,
 
-	accounts: RwLock<Option<Arc<AccountService>>>,		// TODO: this is horrible since AccountService already contains a single RwLock field. refactor.
+	accounts: Option<Arc<AccountProvider>>,
 }
 
 impl Default for Miner {
@@ -58,7 +58,7 @@ impl Default for Miner {
 			gas_floor_target: RwLock::new(U256::zero()),
 			author: RwLock::new(Address::default()),
 			extra_data: RwLock::new(Vec::new()),
-			accounts: RwLock::new(None),
+			accounts: None,
 			spec: Spec::new_test(),
 		}
 	}
@@ -76,13 +76,13 @@ impl Miner {
 			gas_floor_target: RwLock::new(U256::zero()),
 			author: RwLock::new(Address::default()),
 			extra_data: RwLock::new(Vec::new()),
-			accounts: RwLock::new(None),
+			accounts: None,
 			spec: spec,
 		})
 	}
 
 	/// Creates new instance of miner
-	pub fn with_accounts(force_sealing: bool, spec: Spec, accounts: Arc<AccountService>) -> Arc<Miner> {
+	pub fn with_accounts(force_sealing: bool, spec: Spec, accounts: Arc<AccountProvider>) -> Arc<Miner> {
 		Arc::new(Miner {
 			transaction_queue: Mutex::new(TransactionQueue::new()),
 			force_sealing: force_sealing,
@@ -92,7 +92,7 @@ impl Miner {
 			gas_floor_target: RwLock::new(U256::zero()),
 			author: RwLock::new(Address::default()),
 			extra_data: RwLock::new(Vec::new()),
-			accounts: RwLock::new(Some(accounts)),
+			accounts: Some(accounts),
 			spec: spec,
 		})
 	}
@@ -137,7 +137,7 @@ impl Miner {
 						Err(Error::Execution(ExecutionError::BlockGasLimitReached { gas_limit, gas_used, .. })) => {
 							trace!(target: "miner", "Skipping adding transaction to block because of gas limit: {:?}", hash);
 							// Exit early if gas left is smaller then min_tx_gas
-							let min_tx_gas: U256 = x!(21000);	// TODO: figure this out properly.
+							let min_tx_gas: U256 = 21000.into();	// TODO: figure this out properly.
 							if gas_limit - gas_used < min_tx_gas {
 								break;
 							}
@@ -177,9 +177,8 @@ impl Miner {
 			if !block.transactions().is_empty() {
 				trace!(target: "miner", "prepare_sealing: block has transaction - attempting internal seal.");
 				// block with transactions - see if we can seal immediately.
-				let a = self.accounts.read().unwrap();
-				let s = self.engine().generate_seal(block.block(), match *a.deref() {
-					Some(ref x) => Some(x.deref() as &AccountProvider),
+				let s = self.engine().generate_seal(block.block(), match self.accounts {
+					Some(ref x) => Some(&**x),
 					None => None,
 				});
 				if let Some(seal) = s {
@@ -337,11 +336,11 @@ impl MinerService for Miner {
 
 	fn sensible_gas_price(&self) -> U256 {
 		// 10% above our minimum.
-		*self.transaction_queue.lock().unwrap().minimal_gas_price() * x!(110) / x!(100)
+		*self.transaction_queue.lock().unwrap().minimal_gas_price() * 110.into() / 100.into()
 	}
 
 	fn sensible_gas_limit(&self) -> U256 {
-		*self.gas_floor_target.read().unwrap() / x!(5)
+		*self.gas_floor_target.read().unwrap() / 5.into()
 	}
 
 	fn transactions_limit(&self) -> usize {
diff --git a/parity/cli.rs b/parity/cli.rs
index 60b622bf7..95b77a00d 100644
--- a/parity/cli.rs
+++ b/parity/cli.rs
@@ -76,13 +76,13 @@ API and Console Options:
                            interface. APIS is a comma-delimited list of API
                            name. Possible name are web3, eth, net, personal,
                            ethcore, traces.
-                           [default: web3,eth,net,personal,ethcore,traces].
+                           [default: web3,eth,net,personal,traces].
 
   --ipc-off                Disable JSON-RPC over IPC service.
   --ipc-path PATH          Specify custom path for JSON-RPC over IPC service
                            [default: $HOME/.parity/jsonrpc.ipc].
   --ipc-apis APIS          Specify custom API set available via JSON-RPC over
-                           IPC [default: web3,eth,net,personal,ethcore].
+                           IPC [default: web3,eth,net,personal,traces].
 
   --dapps-off              Disable the Dapps server (e.g. status page).
   --dapps-port PORT        Specify the port portion of the Dapps server
diff --git a/rpc/src/v1/tests/eth.rs b/rpc/src/v1/tests/eth.rs
index 80a856aca..80aa8ce33 100644
--- a/rpc/src/v1/tests/eth.rs
+++ b/rpc/src/v1/tests/eth.rs
@@ -19,151 +19,25 @@ use std::collections::HashMap;
 use std::sync::Arc;
 use std::str::FromStr;
 
-use ethcore::client::{BlockChainClient, Client, ClientConfig};
-use ethcore::spec::Genesis;
+use ethcore::ids::BlockID;
+use ethcore::client::{Client, BlockChainClient, ClientConfig};
+use ethcore::spec::{Genesis, Spec};
 use ethcore::block::Block;
+use ethcore::views::BlockView;
 use ethcore::ethereum;
-use ethcore::transaction::{Transaction, Action};
-use ethminer::{MinerService, ExternalMiner};
+use ethminer::{Miner, MinerService, ExternalMiner};
 use devtools::RandomTempPath;
+use util::Hashable;
 use util::io::IoChannel;
-use util::hash::Address;
-use util::numbers::{Uint, U256};
+use util::hash::{Address, H256};
+use util::numbers::U256;
 use util::keys::{AccountProvider, TestAccount, TestAccountProvider};
 use jsonrpc_core::IoHandler;
 use ethjson::blockchain::BlockChain;
 
-use v1::traits::eth::Eth;
-use v1::impls::EthClient;
-use v1::tests::helpers::{TestSyncProvider, Config, TestMinerService};
-
-struct EthTester {
-	_client: Arc<BlockChainClient>,
-	_miner: Arc<MinerService>,
-	accounts: Arc<TestAccountProvider>,
-	handler: IoHandler,
-}
-
-#[test]
-fn harness_works() {
-	let chain: BlockChain = extract_chain!("BlockchainTests/bcUncleTest");
-	chain_harness(chain, |_| {});
-}
-
-#[test]
-fn eth_get_balance() {
-	let chain = extract_chain!("BlockchainTests/bcWalletTest", "wallet2outOf3txs");
-	chain_harness(chain, |tester| {
-		// final account state
-		let req_latest = r#"{
-			"jsonrpc": "2.0",
-			"method": "eth_getBalance",
-			"params": ["0xaaaf5374fce5edbc8e2a8697c15331677e6ebaaa", "latest"],
-			"id": 1
-		}"#;
-		let res_latest = r#"{"jsonrpc":"2.0","result":"0x09","id":1}"#.to_owned();
-		assert_eq!(tester.handler.handle_request(req_latest).unwrap(), res_latest);
-
-		// non-existant account
-		let req_new_acc = r#"{
-			"jsonrpc": "2.0",
-			"method": "eth_getBalance",
-			"params": ["0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"],
-			"id": 3
-		}"#;
-
-		let res_new_acc = r#"{"jsonrpc":"2.0","result":"0x00","id":3}"#.to_owned();
-		assert_eq!(tester.handler.handle_request(req_new_acc).unwrap(), res_new_acc);
-	});
-}
-
-#[test]
-fn eth_block_number() {
-	let chain = extract_chain!("BlockchainTests/bcRPC_API_Test");
-	chain_harness(chain, |tester| {
-		let req_number = r#"{
-			"jsonrpc": "2.0",
-			"method": "eth_blockNumber",
-			"params": [],
-			"id": 1
-		}"#;
-
-		let res_number = r#"{"jsonrpc":"2.0","result":"0x20","id":1}"#.to_owned();
-		assert_eq!(tester.handler.handle_request(req_number).unwrap(), res_number);
-	});
-}
-
-#[cfg(test)]
-#[test]
-fn eth_transaction_count() {
-	let chain = extract_chain!("BlockchainTests/bcRPC_API_Test");
-	chain_harness(chain, |tester| {
-		let address = tester.accounts.new_account("123").unwrap();
-		let secret = tester.accounts.account_secret(&address).unwrap();
-
-		let req_before = r#"{
-			"jsonrpc": "2.0",
-			"method": "eth_getTransactionCount",
-			"params": [""#.to_owned() + format!("0x{:?}", address).as_ref() + r#"", "latest"],
-			"id": 15
-		}"#;
-
-		let res_before = r#"{"jsonrpc":"2.0","result":"0x00","id":15}"#;
-
-		assert_eq!(tester.handler.handle_request(&req_before).unwrap(), res_before);
-
-		let t = Transaction {
-			nonce: U256::zero(),
-			gas_price: U256::from(0x9184e72a000u64),
-			gas: U256::from(0x76c0),
-			action: Action::Call(Address::from_str("d46e8dd67c5d32be8058bb8eb970870f07244567").unwrap()),
-			value: U256::from(0x9184e72au64),
-			data: vec![]
-		}.sign(&secret);
-
-		let req_send_trans = r#"{
-			"jsonrpc": "2.0",
-			"method": "eth_sendTransaction",
-			"params": [{
-				"from": ""#.to_owned() + format!("0x{:?}", address).as_ref() + r#"",
-				"to": "0xd46e8dd67c5d32be8058bb8eb970870f07244567",
-				"gas": "0x76c0",
-				"gasPrice": "0x9184e72a000",
-				"value": "0x9184e72a"
-			}],
-			"id": 16
-		}"#;
-
-		let res_send_trans = r#"{"jsonrpc":"2.0","result":""#.to_owned() + format!("0x{:?}", t.hash()).as_ref() + r#"","id":16}"#;
-
-		// dispatch the transaction.
-		assert_eq!(tester.handler.handle_request(&req_send_trans).unwrap(), res_send_trans);
-
-		// we have submitted the transaction -- but this shouldn't be reflected in a "latest" query.
-		let req_after_latest = r#"{
-			"jsonrpc": "2.0",
-			"method": "eth_getTransactionCount",
-			"params": [""#.to_owned() + format!("0x{:?}", address).as_ref() + r#"", "latest"],
-			"id": 17
-		}"#;
-
-		let res_after_latest = r#"{"jsonrpc":"2.0","result":"0x00","id":17}"#;
-
-		assert_eq!(&tester.handler.handle_request(&req_after_latest).unwrap(), res_after_latest);
-
-		// the pending transactions should have been updated.
-		let req_after_pending = r#"{
-			"jsonrpc": "2.0",
-			"method": "eth_getTransactionCount",
-			"params": [""#.to_owned() + format!("0x{:?}", address).as_ref() + r#"", "pending"],
-			"id": 18
-		}"#;
-
-		let res_after_pending = r#"{"jsonrpc":"2.0","result":"0x01","id":18}"#;
-
-		assert_eq!(&tester.handler.handle_request(&req_after_pending).unwrap(), res_after_pending);
-	});
-}
+use v1::traits::eth::{Eth, EthSigning};
+use v1::impls::{EthClient, EthSigningUnsafeClient};
+use v1::tests::helpers::{TestSyncProvider, Config};
 
 fn account_provider() -> Arc<TestAccountProvider> {
 	let mut accounts = HashMap::new();
@@ -179,51 +53,308 @@ fn sync_provider() -> Arc<TestSyncProvider> {
 	}))
 }
 
-fn miner_service() -> Arc<TestMinerService> {
-	Arc::new(TestMinerService::default())
+fn miner_service(spec: Spec, accounts: Arc<AccountProvider>) -> Arc<Miner> {
+	Miner::with_accounts(true, spec, accounts)
 }
 
-// given a blockchain, this harness will create an EthClient wrapping it
-// which tests can pass specially crafted requests to.
-fn chain_harness<F, U>(chain: BlockChain, mut cb: F) -> U
-	where F: FnMut(&EthTester) -> U {
+fn make_spec(chain: &BlockChain) -> Spec {
 	let genesis = Genesis::from(chain.genesis());
 	let mut spec = ethereum::new_frontier_test();
 	let state = chain.pre_state.clone().into();
 	spec.set_genesis_state(state);
 	spec.overwrite_genesis_params(genesis);
 	assert!(spec.is_state_root_valid());
+	spec
+}
 
-	let dir = RandomTempPath::new();
-	let client = Client::new(ClientConfig::default(), spec, dir.as_path(), IoChannel::disconnected()).unwrap();
-	let sync_provider = sync_provider();
-	let miner_service = miner_service();
-	let account_provider = account_provider();
-	let external_miner = Arc::new(ExternalMiner::default());
+struct EthTester {
+	_miner: Arc<MinerService>,
+	client: Arc<Client>,
+	accounts: Arc<TestAccountProvider>,
+	handler: IoHandler,
+}
 
-	for b in &chain.blocks_rlp() {
-		if Block::is_good(&b) {
-			let _ = client.import_block(b.clone());
-			client.flush_queue();
-			client.import_verified_blocks(&IoChannel::disconnected());
+impl EthTester {
+	fn from_chain(chain: &BlockChain) -> Self {
+		let tester = Self::from_spec_provider(|| make_spec(chain));
+
+		for b in &chain.blocks_rlp() {
+			if Block::is_good(&b) {
+				let _ = tester.client.import_block(b.clone());
+				tester.client.flush_queue();
+				tester.client.import_verified_blocks(&IoChannel::disconnected());
+			}
+		}
+
+		tester.client.flush_queue();
+
+		assert!(tester.client.chain_info().best_block_hash == chain.best_block.clone().into());
+		tester
+	}
+
+	fn from_spec_provider<F>(spec_provider: F) -> Self
+		where F: Fn() -> Spec {
+
+		let dir = RandomTempPath::new();
+		let client = Client::new(ClientConfig::default(), spec_provider(), dir.as_path(), IoChannel::disconnected()).unwrap();
+		let sync_provider = sync_provider();
+		let account_provider = account_provider();
+		let miner_service = miner_service(spec_provider(), account_provider.clone());
+		let external_miner = Arc::new(ExternalMiner::default());
+
+		let eth_client = EthClient::new(
+			&client,
+			&sync_provider,
+			&account_provider,
+			&miner_service,
+			&external_miner
+		);
+		let eth_sign = EthSigningUnsafeClient::new(
+			&client,
+			&account_provider,
+			&miner_service
+		);
+
+		let handler = IoHandler::new();
+		handler.add_delegate(eth_client.to_delegate());
+		handler.add_delegate(eth_sign.to_delegate());
+
+		EthTester {
+			_miner: miner_service,
+			client: client,
+			accounts: account_provider,
+			handler: handler,
+		}
+	}
+}
+
+#[test]
+fn harness_works() {
+	let chain: BlockChain = extract_chain!("BlockchainTests/bcUncleTest");
+	let _ = EthTester::from_chain(&chain);
+}
+
+#[test]
+fn eth_get_balance() {
+	let chain = extract_chain!("BlockchainTests/bcWalletTest", "wallet2outOf3txs");
+	let tester = EthTester::from_chain(&chain);
+	// final account state
+	let req_latest = r#"{
+		"jsonrpc": "2.0",
+		"method": "eth_getBalance",
+		"params": ["0xaaaf5374fce5edbc8e2a8697c15331677e6ebaaa", "latest"],
+		"id": 1
+	}"#;
+	let res_latest = r#"{"jsonrpc":"2.0","result":"0x09","id":1}"#.to_owned();
+	assert_eq!(tester.handler.handle_request(req_latest).unwrap(), res_latest);
+
+	// non-existant account
+	let req_new_acc = r#"{
+		"jsonrpc": "2.0",
+		"method": "eth_getBalance",
+		"params": ["0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"],
+		"id": 3
+	}"#;
+
+	let res_new_acc = r#"{"jsonrpc":"2.0","result":"0x00","id":3}"#.to_owned();
+	assert_eq!(tester.handler.handle_request(req_new_acc).unwrap(), res_new_acc);
+}
+
+#[test]
+fn eth_block_number() {
+	let chain = extract_chain!("BlockchainTests/bcRPC_API_Test");
+	let tester = EthTester::from_chain(&chain);
+	let req_number = r#"{
+		"jsonrpc": "2.0",
+		"method": "eth_blockNumber",
+		"params": [],
+		"id": 1
+	}"#;
+
+	let res_number = r#"{"jsonrpc":"2.0","result":"0x20","id":1}"#.to_owned();
+	assert_eq!(tester.handler.handle_request(req_number).unwrap(), res_number);
+}
+
+// a frontier-like test with an expanded gas limit and balance on known account.
+const TRANSACTION_COUNT_SPEC: &'static [u8] = br#"{
+	"name": "Frontier (Test)",
+	"engine": {
+		"Ethash": {
+			"params": {
+				"gasLimitBoundDivisor": "0x0400",
+				"minimumDifficulty": "0x020000",
+				"difficultyBoundDivisor": "0x0800",
+				"durationLimit": "0x0d",
+				"blockReward": "0x4563918244F40000",
+				"registrar" : "0xc6d9d2cd449a754c494264e1809c50e34d64562b",
+				"frontierCompatibilityModeLimit": "0xffffffffffffffff"
+			}
+		}
+	},
+	"params": {
+		"accountStartNonce": "0x00",
+		"maximumExtraDataSize": "0x20",
+		"minGasLimit": "0x50000",
+		"networkID" : "0x1"
+	},
+	"genesis": {
+		"seal": {
+			"ethereum": {
+				"nonce": "0x0000000000000042",
+				"mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000"
+			}
+		},
+		"difficulty": "0x400000000",
+		"author": "0x0000000000000000000000000000000000000000",
+		"timestamp": "0x00",
+		"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
+		"extraData": "0x11bbe8db4e347b4e8c937c1c8370e4b5ed33adb3db69cbdb7a38e1e50b1b82fa",
+		"gasLimit": "0x50000"
+	},
+	"accounts": {
+		"0000000000000000000000000000000000000001": { "builtin": { "name": "ecrecover", "pricing": { "linear": { "base": 3000, "word": 0 } } } },
+		"0000000000000000000000000000000000000002": { "builtin": { "name": "sha256", "pricing": { "linear": { "base": 60, "word": 12 } } } },
+		"0000000000000000000000000000000000000003": { "builtin": { "name": "ripemd160", "pricing": { "linear": { "base": 600, "word": 120 } } } },
+		"0000000000000000000000000000000000000004": { "builtin": { "name": "identity", "pricing": { "linear": { "base": 15, "word": 3 } } } },
+		"faa34835af5c2ea724333018a515fbb7d5bc0b33": { "balance": "10000000000000", "nonce": "0" }
+	}
+}
+"#;
+
+#[test]
+fn eth_transaction_count() {
+	use util::crypto::Secret;
+
+	let address = Address::from_str("faa34835af5c2ea724333018a515fbb7d5bc0b33").unwrap();
+	let secret = Secret::from_str("8a283037bb19c4fed7b1c569e40c7dcff366165eb869110a1b11532963eb9cb2").unwrap();
+
+	let tester = EthTester::from_spec_provider(|| Spec::load(TRANSACTION_COUNT_SPEC));
+	tester.accounts.accounts.write().unwrap().insert(address, TestAccount {
+		unlocked: false,
+		password: "123".into(),
+		secret: secret
+	});
+
+	let req_before = r#"{
+		"jsonrpc": "2.0",
+		"method": "eth_getTransactionCount",
+		"params": [""#.to_owned() + format!("0x{:?}", address).as_ref() + r#"", "latest"],
+		"id": 15
+	}"#;
+
+	let res_before = r#"{"jsonrpc":"2.0","result":"0x00","id":15}"#;
+
+	assert_eq!(tester.handler.handle_request(&req_before).unwrap(), res_before);
+
+	let req_send_trans = r#"{
+		"jsonrpc": "2.0",
+		"method": "eth_sendTransaction",
+		"params": [{
+			"from": ""#.to_owned() + format!("0x{:?}", address).as_ref() + r#"",
+			"to": "0xd46e8dd67c5d32be8058bb8eb970870f07244567",
+			"gas": "0x30000",
+			"gasPrice": "0x01",
+			"value": "0x9184e72a"
+		}],
+		"id": 16
+	}"#;
+
+	// dispatch the transaction.
+	tester.handler.handle_request(&req_send_trans).unwrap();
+
+	// we have submitted the transaction -- but this shouldn't be reflected in a "latest" query.
+	let req_after_latest = r#"{
+		"jsonrpc": "2.0",
+		"method": "eth_getTransactionCount",
+		"params": [""#.to_owned() + format!("0x{:?}", address).as_ref() + r#"", "latest"],
+		"id": 17
+	}"#;
+
+	let res_after_latest = r#"{"jsonrpc":"2.0","result":"0x00","id":17}"#;
+
+	assert_eq!(&tester.handler.handle_request(&req_after_latest).unwrap(), res_after_latest);
+
+	// the pending transactions should have been updated.
+	let req_after_pending = r#"{
+		"jsonrpc": "2.0",
+		"method": "eth_getTransactionCount",
+		"params": [""#.to_owned() + format!("0x{:?}", address).as_ref() + r#"", "pending"],
+		"id": 18
+	}"#;
+
+	let res_after_pending = r#"{"jsonrpc":"2.0","result":"0x01","id":18}"#;
+
+	assert_eq!(&tester.handler.handle_request(&req_after_pending).unwrap(), res_after_pending);
+}
+
+fn verify_transaction_counts(name: String, chain: BlockChain) {
+	struct PanicHandler(String);
+	impl Drop for PanicHandler {
+		fn drop(&mut self) {
+			if ::std::thread::panicking() {
+				println!("Test failed: {}", self.0);
+			}
 		}
 	}
 
-	assert!(client.chain_info().best_block_hash == chain.best_block.into());
+	let _panic = PanicHandler(name);
 
-	let eth_client = EthClient::new(&client, &sync_provider, &account_provider,
-		&miner_service, &external_miner);
+	fn by_hash(hash: H256, count: usize, id: &mut usize) -> (String, String) {
+		let req = r#"{
+			"jsonrpc": "2.0",
+			"method": "eth_getBlockTransactionCountByHash",
+			"params": [
+				""#.to_owned() + format!("0x{:?}", hash).as_ref() + r#""
+			],
+			"id": "# + format!("{}", *id).as_ref() + r#"
+		}"#;
 
-	let handler = IoHandler::new();
-	let delegate = eth_client.to_delegate();
-	handler.add_delegate(delegate);
+		let res = r#"{"jsonrpc":"2.0","result":""#.to_owned()
+			+ format!("0x{:02x}", count).as_ref()
+			+ r#"","id":"#
+			+ format!("{}", *id).as_ref() + r#"}"#;
+		*id += 1;
+		(req, res)
+	}
 
-	let tester = EthTester {
-		_miner: miner_service,
-		_client: client,
-		accounts: account_provider,
-		handler: handler,
-	};
+	fn by_number(num: u64, count: usize, id: &mut usize) -> (String, String) {
+		let req = r#"{
+			"jsonrpc": "2.0",
+			"method": "eth_getBlockTransactionCountByNumber",
+			"params": [
+				"#.to_owned() + &::serde_json::to_string(&U256::from(num)).unwrap() + r#"
+			],
+			"id": "# + format!("{}", *id).as_ref() + r#"
+		}"#;
 
-	cb(&tester)
+		let res = r#"{"jsonrpc":"2.0","result":""#.to_owned()
+			+ format!("0x{:02x}", count).as_ref()
+			+ r#"","id":"#
+			+ format!("{}", *id).as_ref() + r#"}"#;
+		*id += 1;
+		(req, res)
+	}
+
+	let tester = EthTester::from_chain(&chain);
+
+	let mut id = 1;
+	for b in chain.blocks_rlp().iter().filter(|b| Block::is_good(b)).map(|b| BlockView::new(b)) {
+		let count = b.transactions_count();
+
+		let hash = b.sha3();
+		let number = b.header_view().number();
+
+		let (req, res) = by_hash(hash, count, &mut id);
+		assert_eq!(tester.handler.handle_request(&req), Some(res));
+
+		// uncles can share block numbers, so skip them.
+		if tester.client.block_hash(BlockID::Number(number)) == Some(hash) {
+			let (req, res) = by_number(number, count, &mut id);
+			assert_eq!(tester.handler.handle_request(&req), Some(res));
+		}
+	}
 }
+
+register_test!(eth_transaction_count_1, verify_transaction_counts, "BlockchainTests/bcWalletTest");
+register_test!(eth_transaction_count_2, verify_transaction_counts, "BlockchainTests/bcTotalDifficultyTest");
+register_test!(eth_transaction_count_3, verify_transaction_counts, "BlockchainTests/bcGasPricerTest");
diff --git a/rpc/src/v1/tests/mod.rs b/rpc/src/v1/tests/mod.rs
index 3455bfd1f..a48727475 100644
--- a/rpc/src/v1/tests/mod.rs
+++ b/rpc/src/v1/tests/mod.rs
@@ -13,11 +13,15 @@ pub mod helpers;
 //     extract the chain with that name. This will panic if no chain by that name
 //     is found.
 macro_rules! extract_chain {
-	($file:expr, $name:expr) => {{
+	(iter $file:expr) => {{
 		const RAW_DATA: &'static [u8] =
 			include_bytes!(concat!("../../../../ethcore/res/ethereum/tests/", $file, ".json"));
+		::ethjson::blockchain::Test::load(RAW_DATA).unwrap().into_iter()
+	}};
+
+	($file:expr, $name:expr) => {{
 		let mut chain = None;
-		for (name, c) in ::ethjson::blockchain::Test::load(RAW_DATA).unwrap() {
+		for (name, c) in extract_chain!(iter $file) {
 			if name == $name {
 				chain = Some(c);
 				break;
@@ -27,14 +31,41 @@ macro_rules! extract_chain {
 	}};
 
 	($file:expr) => {{
-		const RAW_DATA: &'static [u8] =
-			include_bytes!(concat!("../../../../ethcore/res/ethereum/tests/", $file, ".json"));
-
-		::ethjson::blockchain::Test::load(RAW_DATA)
-			.unwrap().into_iter().next().unwrap().1
+		extract_chain!(iter $file).next().unwrap().1
 	}};
 }
 
+macro_rules! register_test {
+	($name:ident, $cb:expr, $file:expr) => {
+		#[test]
+		fn $name() {
+			for (name, chain) in extract_chain!(iter $file) {
+				$cb(name, chain);
+			}
+		}
+	};
+
+	(heavy $name:ident, $cb:expr, $file:expr) => {
+		#[test]
+		#[cfg(feature = "test-heavy")]
+		fn $name() {
+			for (name, chain) in extract_chain!(iter $file) {
+				$cb(name, chain);
+			}
+		}
+	};
+
+	(ignore $name:ident, $cb:expr, $file:expr) => {
+		#[test]
+		#[ignore]
+		fn $name() {
+			for (name, chain) in extract_chain!(iter $file) {
+				$cb(name, chain);
+			}
+		}
+	};
+}
+
 #[cfg(test)]
 mod mocked;
 #[cfg(test)]
diff --git a/sync/src/chain.rs b/sync/src/chain.rs
index 2f31f1d47..dcfdc1c16 100644
--- a/sync/src/chain.rs
+++ b/sync/src/chain.rs
@@ -1310,8 +1310,8 @@ mod tests {
 
 	fn get_dummy_block(order: u32, parent_hash: H256) -> Bytes {
 		let mut header = Header::new();
-		header.gas_limit = x!(0);
-		header.difficulty = x!(order * 100);
+		header.gas_limit = 0.into();
+		header.difficulty = (order * 100).into();
 		header.timestamp = (order * 10) as u64;
 		header.number = order as u64;
 		header.parent_hash = parent_hash;
@@ -1327,7 +1327,7 @@ mod tests {
 	fn get_dummy_blocks(order: u32, parent_hash: H256) -> Bytes {
 		let mut rlp = RlpStream::new_list(1);
 		rlp.append_raw(&get_dummy_block(order, parent_hash), 1);
-		let difficulty: U256 = x!(100 * order);
+		let difficulty: U256 = (100 * order).into();
 		rlp.append(&difficulty);
 		rlp.out()
 	}
diff --git a/util/src/common.rs b/util/src/common.rs
index a4ba41f82..0e0cd7757 100644
--- a/util/src/common.rs
+++ b/util/src/common.rs
@@ -26,44 +26,50 @@ pub use sha3::*;
 
 #[macro_export]
 macro_rules! hash_map {
-	( $( $x:expr => $y:expr ),* ) => {
-		vec![ $( ($x, $y) ),* ].into_iter().collect::<HashMap<_, _>>()
-	}
+	() => { HashMap::new() };
+	( $( $x:expr => $y:expr ),* ) => {{
+		let mut x = HashMap::new();
+		$(
+			x.insert($x, $y);
+		)*
+		x
+	}}
 }
 
 #[macro_export]
-macro_rules! hash_mapx {
-	( $( $x:expr => $y:expr ),* ) => {
-		vec![ $( ( From::from($x), From::from($y) ) ),* ].into_iter().collect::<HashMap<_, _>>()
-	}
+macro_rules! hash_map_into {
+	() => { HashMap::new() };
+	( $( $x:expr => $y:expr ),* ) => {{
+		let mut x = HashMap::new();
+		$(
+			x.insert($x.into(), $y.into());
+		)*
+		x
+	}}
 }
 
 #[macro_export]
 macro_rules! map {
-	( $( $x:expr => $y:expr ),* ) => {
-		vec![ $( ($x, $y) ),* ].into_iter().collect::<BTreeMap<_, _>>()
-	}
+	() => { BTreeMap::new() };
+	( $( $x:expr => $y:expr ),* ) => {{
+		let mut x = BTreeMap::new();
+		$(
+			x.insert($x, $y);
+		)*
+		x
+	}}
 }
 
 #[macro_export]
-macro_rules! mapx {
-	( $( $x:expr => $y:expr ),* ) => {
-		vec![ $( ( From::from($x), From::from($y) ) ),* ].into_iter().collect::<BTreeMap<_, _>>()
-	}
-}
-
-#[macro_export]
-macro_rules! x {
-	( $x:expr ) => {
-		From::from($x)
-	}
-}
-
-#[macro_export]
-macro_rules! xx {
-	( $x:expr ) => {
-		From::from(From::from($x))
-	}
+macro_rules! map_into {
+	() => { BTreeMap::new() };
+	( $( $x:expr => $y:expr ),* ) => {{
+		let mut x = BTreeMap::new();
+		$(
+			x.insert($x.into(), $y.into());
+		)*
+		x
+	}}
 }
 
 #[macro_export]
diff --git a/util/src/hash.rs b/util/src/hash.rs
index ba96f812c..1a16cefa4 100644
--- a/util/src/hash.rs
+++ b/util/src/hash.rs
@@ -718,7 +718,7 @@ mod tests {
 
 	#[test]
 	fn from_and_to_u256() {
-		let u: U256 = x!(0x123456789abcdef0u64);
+		let u: U256 = 0x123456789abcdef0u64.into();
 		let h = H256::from(u);
 		assert_eq!(H256::from(u), H256::from("000000000000000000000000000000000000000000000000123456789abcdef0"));
 		let h_ref = H256::from(&u);
diff --git a/util/src/json_aid.rs b/util/src/json_aid.rs
index 6aed7f09c..7bf940b99 100644
--- a/util/src/json_aid.rs
+++ b/util/src/json_aid.rs
@@ -48,7 +48,7 @@ impl FromJson for Bytes {
 impl FromJson for BTreeMap<H256, H256> {
 	fn from_json(json: &Json) -> Self {
 		match *json {
-			Json::Object(ref o) => o.iter().map(|(key, value)| (x!(&u256_from_str(key)), x!(&U256::from_json(value)))).collect(),
+			Json::Object(ref o) => o.iter().map(|(key, value)| (u256_from_str(key).into(), U256::from_json(value).into())).collect(),
 			_ => BTreeMap::new(),
 		}
 	}
diff --git a/util/src/keys/store.rs b/util/src/keys/store.rs
index 3ecabc07c..f6f41745f 100644
--- a/util/src/keys/store.rs
+++ b/util/src/keys/store.rs
@@ -87,7 +87,7 @@ struct AccountUnlock {
 }
 
 /// Basic account management trait
-pub trait AccountProvider : Send + Sync {
+pub trait AccountProvider: Send + Sync {
 	/// Lists all accounts
 	fn accounts(&self) -> Result<Vec<Address>, ::std::io::Error>;
 	/// Unlocks account with the password provided
@@ -325,7 +325,7 @@ impl SecretStore {
 		ret
 	}
 
-	/// Returns secret for unlocked account.
+	/// Returns secret for locked account.
 	pub fn locked_account_secret(&self, account: &Address, pass: &str) -> Result<crypto::Secret, SigningError> {
 		let secret_id = try!(self.account(&account).ok_or(SigningError::NoAccount));
 		self.get(&secret_id, pass).or_else(|e| Err(match e {
@@ -554,7 +554,7 @@ mod tests {
 						H256::from_str("517ead924a9d0dc3124507e3393d175ce3ff7c1e96529c6c555ce9e51205e9b2").unwrap(),
 						262144,
 						32));
-			key_file.account = Some(x!(i as u64));
+			key_file.account = Some((i as u64).into());
 			result.push(key_file.id.clone());
 			write_sstore.import_key(key_file).unwrap();
 		}
@@ -627,7 +627,7 @@ mod tests {
 			sstore.sign(&address, &H256::random()).unwrap()
 		};
 
-		assert!(signature != x!(0));
+		assert!(signature != 0.into());
 	}
 
 	#[test]