diff --git a/substrate/Cargo.lock b/substrate/Cargo.lock
index a05893e615..c741c845a5 100644
--- a/substrate/Cargo.lock
+++ b/substrate/Cargo.lock
@@ -553,7 +553,7 @@ dependencies = [
 name = "native-runtime"
 version = "0.1.0"
 dependencies = [
- "runtime-support 0.1.0",
+ "runtime-std 0.1.0",
  "rustc-hex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -726,10 +726,13 @@ dependencies = [
  "assert_matches 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "error-chain 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "native-runtime 0.1.0",
  "parity-wasm 0.15.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "polkadot-primitives 0.1.0",
  "polkadot-serializer 0.1.0",
  "polkadot-state-machine 0.1.0",
+ "runtime-std 0.1.0",
  "rustc-hex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.19 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -913,7 +916,7 @@ dependencies = [
 ]
 
 [[package]]
-name = "runtime-support"
+name = "runtime-std"
 version = "0.1.0"
 dependencies = [
  "environmental 0.1.0",
diff --git a/substrate/build.sh b/substrate/build.sh
new file mode 100755
index 0000000000..40a1043226
--- /dev/null
+++ b/substrate/build.sh
@@ -0,0 +1,6 @@
+#!/bin/sh
+
+cd wasm-runtime
+./build.sh
+cd ..
+
diff --git a/substrate/executor/Cargo.toml b/substrate/executor/Cargo.toml
index 0401bd4c77..5329eb7023 100644
--- a/substrate/executor/Cargo.toml
+++ b/substrate/executor/Cargo.toml
@@ -13,6 +13,9 @@ serde_derive = "1.0"
 parity-wasm = "0.15.0"
 byteorder = "1.1"
 rustc-hex = "1.0.0"
+native-runtime = { path = "../native-runtime", version = "0.1" }
+runtime-std = { path = "../native-runtime/std", version = "0.1" }
+libc = { version = "0.2.33" }
 
 [dev-dependencies]
 assert_matches = "1.1"
diff --git a/substrate/executor/src/error.rs b/substrate/executor/src/error.rs
index 4fd0ec0604..973fa58d38 100644
--- a/substrate/executor/src/error.rs
+++ b/substrate/executor/src/error.rs
@@ -17,7 +17,6 @@
 //! Rust executor possible errors.
 
 use serializer;
-use state_machine;
 
 error_chain! {
 	foreign_links {
@@ -38,9 +37,9 @@ error_chain! {
 		}
 
 		/// Externalities have failed.
-		Externalities(e: Box<state_machine::Error>) {
+		Externalities {
 			description("externalities failure"),
-			display("Externalities error: {}", e),
+			display("Externalities error"),
 		}
 
 		/// Invalid index.
@@ -60,5 +59,11 @@ error_chain! {
 			description("runtime failure"),
 			display("Runtime error"),
 		}
+
+		/// Runtime failed.
+		InvalidMemoryReference {
+			description("invalid memory reference"),
+			display("Invalid memory reference"),
+		}
 	}
 }
diff --git a/substrate/executor/src/lib.rs b/substrate/executor/src/lib.rs
index f1da582538..9935f8aec8 100644
--- a/substrate/executor/src/lib.rs
+++ b/substrate/executor/src/lib.rs
@@ -34,6 +34,9 @@ extern crate serde;
 extern crate parity_wasm;
 extern crate byteorder;
 extern crate rustc_hex;
+extern crate native_runtime;
+extern crate runtime_std;
+extern crate libc;
 
 #[macro_use]
 extern crate error_chain;
@@ -44,10 +47,11 @@ extern crate assert_matches;
 #[macro_use]
 mod wasm_utils;
 mod wasm_executor;
+mod native_executor;
 
 pub mod error;
 
 /// Creates new RustExecutor for contracts.
-pub fn executor() -> wasm_executor::WasmExecutor {
-	wasm_executor::WasmExecutor::default()
+pub fn executor() -> native_executor::NativeExecutor {
+	native_executor::NativeExecutor
 }
diff --git a/substrate/executor/src/native_executor.rs b/substrate/executor/src/native_executor.rs
new file mode 100644
index 0000000000..b8c90f2d9a
--- /dev/null
+++ b/substrate/executor/src/native_executor.rs
@@ -0,0 +1,110 @@
+use std::panic::catch_unwind;
+use primitives::contract::CallData;
+use state_machine::{Externalities, CodeExecutor};
+use error::{Error, ErrorKind, Result};
+use wasm_executor::WasmExecutor;
+use native_runtime as runtime;
+use runtime_std;
+
+pub struct NativeExecutor;
+
+fn safe_call<F: ::std::panic::UnwindSafe + FnOnce() -> Vec<u8>>(f: F) -> Result<Vec<u8>> {
+	catch_unwind(f).map_err(|_| ErrorKind::Runtime.into())
+}
+
+impl CodeExecutor for NativeExecutor {
+	type Error = Error;
+
+	fn call<E: Externalities>(
+		&self,
+		ext: &mut E,
+		code: &[u8],
+		method: &str,
+		data: &CallData,
+	) -> Result<Vec<u8>> {
+		// WARNING!!! This assumes that the runtime was built *before* the main project. Until we
+		// get a proper build script, this must be strictly adhered to or things will go wrong.
+		let native_equivalent = include_bytes!("../../wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.compact.wasm");
+		if code == &native_equivalent[..] {
+			runtime_std::with_externalities(ext, || match method {
+				"execute_block" => safe_call(|| runtime::execute_block(&data.0)),
+				"execute_transaction" => safe_call(|| runtime::execute_transaction(&data.0)),
+				_ => Err(ErrorKind::MethodNotFound(method.to_owned()).into()),
+			})
+		} else {
+			// call into wasm.
+			WasmExecutor.call(ext, code, method, data)
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use native_runtime::codec::KeyedVec;
+	use native_runtime::support::{TestExternalities, one, two, StaticHexInto};
+	use native_runtime::runtime::staking::balance;
+	use primitives::twox_128;
+
+	const BLOATY_CODE: &[u8] = include_bytes!("../../wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.wasm");
+	const COMPACT_CODE: &[u8] = include_bytes!("../../wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.compact.wasm");
+	fn tx() -> Vec<u8> { "679fcf0a846b4224c84ecad7d91a26241c46d00cb53d6480a363274e8965ee34b0b80b4b2e3836d3d8f8f12c0c1aef7350af587d9aee3883561d11726068ac0a2f8c6129d816cf51c374bc7f08c3e63ed156cf78aefb4a6550d97b87997977ee00000000000000000228000000d75a980182b10ab7d54bfed3c964073a0ee172f3daa62325af021a68f707511a4500000000000000".convert() }
+
+	#[test]
+	fn panic_execution_with_foreign_code_gives_error() {
+		let one = one();
+		let mut t = TestExternalities { storage: map![
+			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![68u8, 0, 0, 0, 0, 0, 0, 0]
+		], };
+
+		let r = NativeExecutor.call(&mut t, BLOATY_CODE, "execute_transaction", &CallData(tx()));
+		assert!(r.is_err());
+	}
+
+	#[test]
+	fn panic_execution_with_native_equivalent_code_gives_error() {
+		let one = one();
+		let mut t = TestExternalities { storage: map![
+			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![68u8, 0, 0, 0, 0, 0, 0, 0]
+		], };
+
+		let r = NativeExecutor.call(&mut t, COMPACT_CODE, "execute_transaction", &CallData(tx()));
+		assert!(r.is_err());
+	}
+
+	#[test]
+	fn successful_execution_with_native_equivalent_code_gives_ok() {
+		let one = one();
+		let two = two();
+
+		let mut t = TestExternalities { storage: map![
+			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![111u8, 0, 0, 0, 0, 0, 0, 0]
+		], };
+
+		let r = NativeExecutor.call(&mut t, COMPACT_CODE, "execute_transaction", &CallData(tx()));
+		assert!(r.is_ok());
+
+		runtime_std::with_externalities(&mut t, || {
+			assert_eq!(balance(&one), 42);
+			assert_eq!(balance(&two), 69);
+		});
+	}
+
+	#[test]
+	fn successful_execution_with_foreign_code_gives_ok() {
+		let one = one();
+		let two = two();
+
+		let mut t = TestExternalities { storage: map![
+			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![111u8, 0, 0, 0, 0, 0, 0, 0]
+		], };
+
+		let r = NativeExecutor.call(&mut t, BLOATY_CODE, "execute_transaction", &CallData(tx()));
+		assert!(r.is_ok());
+
+		runtime_std::with_externalities(&mut t, || {
+			assert_eq!(balance(&one), 42);
+			assert_eq!(balance(&two), 69);
+		});
+	}
+}
diff --git a/substrate/executor/src/wasm_executor.rs b/substrate/executor/src/wasm_executor.rs
index 7fc9a741f8..439defd449 100644
--- a/substrate/executor/src/wasm_executor.rs
+++ b/substrate/executor/src/wasm_executor.rs
@@ -17,9 +17,10 @@
 //! Rust implementation of Polkadot contracts.
 
 use std::sync::Arc;
+use std::cmp::Ordering;
 use std::collections::HashMap;
 use parity_wasm::{deserialize_buffer, ModuleInstanceInterface, ProgramInstance};
-use parity_wasm::interpreter::{ItemIndex};
+use parity_wasm::interpreter::{ItemIndex, DummyUserError};
 use parity_wasm::RuntimeValue::{I32, I64};
 use primitives::contract::CallData;
 use state_machine::{Externalities, CodeExecutor};
@@ -27,6 +28,7 @@ use error::{Error, ErrorKind, Result};
 use wasm_utils::{MemoryInstance, UserDefinedElements,
 	AddModuleWithoutFullDependentInstance};
 use primitives::{ed25519, blake2_256, twox_128, twox_256};
+use primitives::hexdisplay::HexDisplay;
 
 struct Heap {
 	end: u32,
@@ -77,16 +79,33 @@ impl WritePrimitive<u32> for MemoryInstance {
 }
 
 impl_function_executor!(this: FunctionExecutor<'e, E>,
-	ext_print(utf8_data: *const u8, utf8_len: u32) => {
+	ext_print_utf8(utf8_data: *const u8, utf8_len: u32) => {
 		if let Ok(utf8) = this.memory.get(utf8_data, utf8_len as usize) {
 			if let Ok(message) = String::from_utf8(utf8) {
 				println!("Runtime: {}", message);
 			}
 		}
 	},
+	ext_print_hex(data: *const u8, len: u32) => {
+		if let Ok(hex) = this.memory.get(data, len as usize) {
+			println!("Runtime: {}", HexDisplay::from(&hex));
+		}
+	},
 	ext_print_num(number: u64) => {
 		println!("Runtime: {}", number);
 	},
+	ext_memcmp(s1: *const u8, s2: *const u8, n: usize) -> i32 => {
+		if let (Ok(sl1), Ok(sl2))
+			= (this.memory.get(s1, n as usize), this.memory.get(s2, n as usize)) {
+			match sl1.cmp(&sl2) {
+				Ordering::Greater => 1,
+				Ordering::Less => -1,
+				Ordering::Equal => 0,
+			}
+		} else {
+			return Err(DummyUserError.into());
+		}
+	},
 	ext_memcpy(dest: *mut u8, src: *const u8, count: usize) -> *mut u8 => {
 		let _ = this.memory.copy_nonoverlapping(src as usize, dest as usize, count as usize);
 		println!("memcpy {} from {}, {} bytes", dest, src, count);
@@ -128,11 +147,12 @@ impl_function_executor!(this: FunctionExecutor<'e, E>,
 		this.memory.write_primitive(written_out, written);
 		offset as u32
 	},
-	ext_get_storage_into(key_data: *const u8, key_len: u32, value_data: *mut u8, value_len: u32) -> u32 => {
+	ext_get_storage_into(key_data: *const u8, key_len: u32, value_data: *mut u8, value_len: u32, value_offset: u32) -> u32 => {
 		if let Ok(key) = this.memory.get(key_data, key_len as usize) {
 			if let Ok(value) = this.ext.storage(&key) {
+				let value = &value[value_offset as usize..];
 				let written = ::std::cmp::min(value_len as usize, value.len());
-				let _ = this.memory.set(value_data, &value[0..written]);
+				let _ = this.memory.set(value_data, &value[..written]);
 				written as u32
 			} else { 0 }
 		} else { 0 }
@@ -141,47 +161,63 @@ impl_function_executor!(this: FunctionExecutor<'e, E>,
 		this.ext.chain_id()
 	},
 	ext_twox_128(data: *const u8, len: u32, out: *mut u8) => {
-		let result =
-			if let Ok(value) = this.memory.get(data, len as usize) {
-				twox_128(&value)
-			} else {
-				[0; 16]
-			};
+		let maybe_value = if len == 0 {
+			Ok(vec![])
+		} else {
+			this.memory.get(data, len as usize)
+		};
+		let result = if let Ok(value) = maybe_value {
+			twox_128(&value)
+		} else {
+			[0; 16]
+		};
 		let _ = this.memory.set(out, &result);
 	},
 	ext_twox_256(data: *const u8, len: u32, out: *mut u8) => {
-		let result =
-			if let Ok(value) = this.memory.get(data, len as usize) {
-				twox_256(&value)
-			} else {
-				[0; 32]
-			};
+		let maybe_value = if len == 0 {
+			Ok(vec![])
+		} else {
+			this.memory.get(data, len as usize)
+		};
+		let result = if let Ok(value) = maybe_value {
+			twox_256(&value)
+		} else {
+			[0; 32]
+		};
 		let _ = this.memory.set(out, &result);
 	},
 	ext_blake2_256(data: *const u8, len: u32, out: *mut u8) => {
-		let result =
-			if let Ok(value) = this.memory.get(data, len as usize) {
-				blake2_256(&value)
-			} else {
-				[0; 32]
-			};
+		let maybe_value = if len == 0 {
+			Ok(vec![])
+		} else {
+			this.memory.get(data, len as usize)
+		};
+		let result = if let Ok(value) = maybe_value {
+			blake2_256(&value)
+		} else {
+			[0; 32]
+		};
 		let _ = this.memory.set(out, &result);
 	},
 	ext_ed25519_verify(msg_data: *const u8, msg_len: u32, sig_data: *const u8, pubkey_data: *const u8) -> u32 => {
 		(||{
 			let mut sig = [0u8; 64];
 			if let Err(_) = this.memory.get_into(sig_data, &mut sig[..]) {
-				return 0;
+				return 2;
 			};
 			let mut pubkey = [0u8; 32];
 			if let Err(_) = this.memory.get_into(pubkey_data, &mut pubkey[..]) {
-				return 0;
+				return 3;
 			};
 
 			if let Ok(msg) = this.memory.get(msg_data, msg_len as usize) {
-				if ed25519::Signature::from(sig).verify(&msg, &ed25519::Public::from(pubkey)) { 1 } else { 0 }
+				if ed25519::Signature::from(sig).verify(&msg, &ed25519::Public::from(pubkey)) {
+					0
+				} else {
+					5
+				}
 			} else {
-				0
+				4
 			}
 		})()
 	}
@@ -224,7 +260,9 @@ impl CodeExecutor for WasmExecutor {
 					.add_argument(I32(offset as i32))
 					.add_argument(I32(size as i32)))
 			.and_then(|p| module.execute_export(method, p))
-			.map_err(|_| -> Error { ErrorKind::Runtime.into() })?;
+			.map_err(|_| -> Error {
+				ErrorKind::Runtime.into()
+			})?;
 
 		if let Some(I64(r)) = returned {
 			memory.get(r as u32, (r >> 32) as u32 as usize)
@@ -240,23 +278,31 @@ mod tests {
 
 	use super::*;
 	use rustc_hex::FromHex;
+	use primitives::{blake2_256, twox_128};
+	use runtime_std;
+	use native_runtime::support::{one, two, StaticHexInto, TestExternalities};
+	use native_runtime::codec::KeyedVec;
+	use native_runtime::runtime::staking::balance;
 
-	#[derive(Debug, Default)]
-	struct TestExternalities {
-		storage: HashMap<Vec<u8>, Vec<u8>>,
+	#[test]
+	fn returning_should_work() {
+		let mut ext = TestExternalities::default();
+		let test_code = include_bytes!("../../wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.compact.wasm");
+
+		let output = WasmExecutor.call(&mut ext, &test_code[..], "test_empty_return", &CallData(vec![])).unwrap();
+		assert_eq!(output, vec![0u8; 0]);
 	}
-	impl Externalities for TestExternalities {
-		type Error = Error;
 
-		fn storage(&self, key: &[u8]) -> Result<&[u8]> {
-			Ok(self.storage.get(&key.to_vec()).map_or(&[] as &[u8], Vec::as_slice))
-		}
+	#[test]
+	fn panicking_should_work() {
+		let mut ext = TestExternalities::default();
+		let test_code = include_bytes!("../../wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.compact.wasm");
 
-		fn set_storage(&mut self, key: Vec<u8>, value: Vec<u8>) {
-			self.storage.insert(key, value);
-		}
+		let output = WasmExecutor.call(&mut ext, &test_code[..], "test_panic", &CallData(vec![]));
+		assert!(output.is_err());
 
-		fn chain_id(&self) -> u64 { 42 }
+		let output = WasmExecutor.call(&mut ext, &test_code[..], "test_conditional_panic", &CallData(vec![2]));
+		assert!(output.is_err());
 	}
 
 	#[test]
@@ -283,11 +329,11 @@ mod tests {
 		let test_code = include_bytes!("../../wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.compact.wasm");
 		assert_eq!(
 			WasmExecutor.call(&mut ext, &test_code[..], "test_blake2_256", &CallData(b"".to_vec())).unwrap(),
-			FromHex::from_hex("0e5751c026e543b2e8ab2eb06099daa1d1e5df47778f7787faab45cdf12fe3a8").unwrap()
+			blake2_256(&b""[..]).to_vec()
 		);
 		assert_eq!(
 			WasmExecutor.call(&mut ext, &test_code[..], "test_blake2_256", &CallData(b"Hello world!".to_vec())).unwrap(),
-			FromHex::from_hex("3fbc092db9350757e2ab4f7ee9792bfcd2f5220ada5a4bc684487f60c6034369").unwrap()
+			blake2_256(&b"Hello world!"[..]).to_vec()
 		);
 	}
 
@@ -330,7 +376,40 @@ mod tests {
 		calldata.extend_from_slice(sig.as_ref());
 		assert_eq!(
 			WasmExecutor.call(&mut ext, &test_code[..], "test_ed25519_verify", &CallData(calldata)).unwrap(),
-			vec![1]
+			vec![0]
 		);
 	}
+
+	fn tx() -> Vec<u8> { "679fcf0a846b4224c84ecad7d91a26241c46d00cb53d6480a363274e8965ee34b0b80b4b2e3836d3d8f8f12c0c1aef7350af587d9aee3883561d11726068ac0a2f8c6129d816cf51c374bc7f08c3e63ed156cf78aefb4a6550d97b87997977ee00000000000000000228000000d75a980182b10ab7d54bfed3c964073a0ee172f3daa62325af021a68f707511a4500000000000000".convert() }
+
+	#[test]
+	fn panic_execution_gives_error() {
+		let one = one();
+		let mut t = TestExternalities { storage: map![
+			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![68u8, 0, 0, 0, 0, 0, 0, 0]
+		], };
+
+		let foreign_code = include_bytes!("../../wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.wasm");
+		let r = WasmExecutor.call(&mut t, &foreign_code[..], "execute_transaction", &CallData(tx()));
+		assert!(r.is_err());
+	}
+
+	#[test]
+	fn successful_execution_gives_ok() {
+		let one = one();
+		let two = two();
+
+		let mut t = TestExternalities { storage: map![
+			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![111u8, 0, 0, 0, 0, 0, 0, 0]
+		], };
+
+		let foreign_code = include_bytes!("../../wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.compact.wasm");
+		let r = WasmExecutor.call(&mut t, &foreign_code[..], "execute_transaction", &CallData(tx()));
+		assert!(r.is_ok());
+
+		runtime_std::with_externalities(&mut t, || {
+			assert_eq!(balance(&one), 42);
+			assert_eq!(balance(&two), 69);
+		});
+	}
 }
diff --git a/substrate/native-runtime/Cargo.toml b/substrate/native-runtime/Cargo.toml
index eb5eb82408..25091c2cef 100644
--- a/substrate/native-runtime/Cargo.toml
+++ b/substrate/native-runtime/Cargo.toml
@@ -9,5 +9,5 @@ with-std = []
 without-std = []
 
 [dependencies]
-runtime-support = { path = "./support", version = "0.1" }
+runtime-std = { path = "./std", version = "0.1" }
 rustc-hex = "1.0"
diff --git a/substrate/native-runtime/support/Cargo.toml b/substrate/native-runtime/std/Cargo.toml
similarity index 93%
rename from substrate/native-runtime/support/Cargo.toml
rename to substrate/native-runtime/std/Cargo.toml
index 1c24c014e6..0976e4b378 100644
--- a/substrate/native-runtime/support/Cargo.toml
+++ b/substrate/native-runtime/std/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "runtime-support"
+name = "runtime-std"
 version = "0.1.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 
diff --git a/substrate/native-runtime/support/src/lib.rs b/substrate/native-runtime/std/src/lib.rs
similarity index 70%
rename from substrate/native-runtime/support/src/lib.rs
rename to substrate/native-runtime/std/src/lib.rs
index 91005a2f1d..fb74093d18 100644
--- a/substrate/native-runtime/support/src/lib.rs
+++ b/substrate/native-runtime/std/src/lib.rs
@@ -39,7 +39,8 @@ pub mod prelude {
 	pub use std::boxed::Box;
 }
 
-pub use polkadot_state_machine::Externalities;
+pub use polkadot_state_machine::{Externalities, ExternalitiesError};
+use primitives::hexdisplay::HexDisplay;
 
 // TODO: use the real error, not NoError.
 
@@ -50,29 +51,34 @@ impl fmt::Display for NoError {
 	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "") }
 }
 
-environmental!(ext : Externalities<Error=NoError> + 'static);
+environmental!(ext : trait Externalities);
 
 /// Get `key` from storage and return a `Vec`, empty if there's a problem.
 pub fn storage(key: &[u8]) -> Vec<u8> {
 	ext::with(|ext| ext.storage(key).ok().map(|s| s.to_vec()))
-		.unwrap_or(None)
-		.unwrap_or_else(|| vec![])
+		.expect("read_storage cannot be called outside of an Externalities-provided environment.")
+		.unwrap_or_else(Vec::new)
 }
 
 /// Get `key` from storage, placing the value into `value_out` (as much as possible) and return
 /// the number of bytes that the key in storage was.
-pub fn read_storage(key: &[u8], value_out: &mut [u8]) -> usize {
+pub fn read_storage(key: &[u8], value_out: &mut [u8], value_offset: usize) -> usize {
 	ext::with(|ext| {
 		if let Ok(value) = ext.storage(key) {
+			let value = &value[value_offset..];
 			let written = ::std::cmp::min(value.len(), value_out.len());
 			value_out[0..written].copy_from_slice(&value[0..written]);
 			value.len()
 		} else {
+			// no-entry is treated as an empty vector of bytes.
+			// TODO: consider allowing empty-vector to exist separately to no-entry (i.e. return
+			// Option<usize>)
 			0
 		}
-	}).unwrap_or(0)
+	}).expect("read_storage cannot be called outside of an Externalities-provided environment.")
 }
 
+/// Set the storage to some particular key.
 pub fn set_storage(key: &[u8], value: &[u8]) {
 	ext::with(|ext|
 		ext.set_storage(key.to_vec(), value.to_vec())
@@ -96,10 +102,36 @@ pub fn ed25519_verify(sig: &[u8; 64], msg: &[u8], pubkey: &[u8; 32]) -> bool {
 
 /// Execute the given closure with global function available whose functionality routes into the
 /// externalities `ext`. Forwards the value that the closure returns.
-pub fn with_externalities<R, F: FnOnce() -> R>(ext: &mut (Externalities<Error=NoError> + 'static), f: F) -> R {
+pub fn with_externalities<R, F: FnOnce() -> R>(ext: &mut Externalities, f: F) -> R {
 	ext::using(ext, f)
 }
 
+pub trait Printable {
+	fn print(self);
+}
+
+impl<'a> Printable for &'a [u8] {
+	fn print(self) {
+		println!("Runtime: {}", HexDisplay::from(&self));
+	}
+}
+
+impl<'a> Printable for &'a str {
+	fn print(self) {
+		println!("Runtime: {}", self);
+	}
+}
+
+impl Printable for u64 {
+	fn print(self) {
+		println!("Runtime: {}", self);
+	}
+}
+
+pub fn print<T: Printable + Sized>(value: T) {
+	value.print();
+}
+
 #[macro_export]
 macro_rules! impl_stubs {
 	($( $name:ident ),*) => {}
@@ -115,9 +147,7 @@ mod tests {
 		storage: HashMap<Vec<u8>, Vec<u8>>,
 	}
 	impl Externalities for TestExternalities {
-		type Error = NoError;
-
-		fn storage(&self, key: &[u8]) -> Result<&[u8], NoError> {
+		fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError> {
 			Ok(self.storage.get(&key.to_vec()).map_or(&[] as &[u8], Vec::as_slice))
 		}
 
@@ -154,4 +184,20 @@ mod tests {
 			false
 		}));
 	}
+
+	#[test]
+	fn read_storage_works() {
+		let mut t = TestExternalities { storage: map![
+			b":test".to_vec() => b"\x0b\0\0\0Hello world".to_vec()
+		], };
+
+		with_externalities(&mut t, || {
+			let mut v = [0u8; 4];
+			assert!(read_storage(b":test", &mut v[..], 0) >= 4);
+			assert_eq!(v, [11u8, 0, 0, 0]);
+			let mut w = [0u8; 11];
+			assert!(read_storage(b":test", &mut w[..], 4) >= 11);
+			assert_eq!(&w, b"Hello world");
+		});
+	}
 }
diff --git a/substrate/primitives/src/hexdisplay.rs b/substrate/primitives/src/hexdisplay.rs
index d6299a2e41..fa62d69869 100644
--- a/substrate/primitives/src/hexdisplay.rs
+++ b/substrate/primitives/src/hexdisplay.rs
@@ -39,6 +39,10 @@ pub trait AsBytesRef {
 	fn as_bytes_ref(&self) -> &[u8];
 }
 
+impl<'a> AsBytesRef for &'a [u8] {
+	fn as_bytes_ref(&self) -> &[u8] { self }
+}
+
 impl AsBytesRef for [u8] {
 	fn as_bytes_ref(&self) -> &[u8] { &self }
 }
diff --git a/substrate/state_machine/src/ext.rs b/substrate/state_machine/src/ext.rs
index 1452558ccd..764c51de10 100644
--- a/substrate/state_machine/src/ext.rs
+++ b/substrate/state_machine/src/ext.rs
@@ -19,7 +19,7 @@
 use std::{error, fmt};
 
 use backend::Backend;
-use {Externalities, OverlayedChanges};
+use {Externalities, ExternalitiesError, OverlayedChanges};
 
 /// Errors that can occur when interacting with the externalities.
 #[derive(Debug, Copy, Clone)]
@@ -61,12 +61,10 @@ pub struct Ext<'a, B: 'a> {
 impl<'a, B: 'a> Externalities for Ext<'a, B>
 	where B: Backend
 {
-	type Error = B::Error;
-
-	fn storage(&self, key: &[u8]) -> Result<&[u8], Self::Error> {
+	fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError> {
 		match self.overlay.storage(key) {
 			Some(x) => Ok(x),
-			None => self.backend.storage(key)
+			None => self.backend.storage(key).map_err(|_| ExternalitiesError),
 		}
 	}
 
diff --git a/substrate/state_machine/src/lib.rs b/substrate/state_machine/src/lib.rs
index cd25cdcb90..cd7f9291bb 100644
--- a/substrate/state_machine/src/lib.rs
+++ b/substrate/state_machine/src/lib.rs
@@ -113,6 +113,18 @@ impl OverlayedChanges {
 pub trait Error: 'static + fmt::Debug + fmt::Display + Send {}
 impl<E> Error for E where E: 'static + fmt::Debug + fmt::Display + Send {}
 
+/// Externalities Error.
+///
+/// Externalities are not really allowed to have errors, since it's assumed that dependent code
+/// would not be executed unless externalities were available. This is included for completeness,
+/// and as a transition away from the pre-existing framework.
+#[derive(Debug, Eq, PartialEq)]
+pub struct ExternalitiesError;
+
+impl fmt::Display for ExternalitiesError {
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "Externalities Error") }
+}
+
 fn to_keyed_vec(value: u32, mut prepend: Vec<u8>) -> Vec<u8> {
 	prepend.extend((0..::std::mem::size_of::<u32>()).into_iter().map(|i| (value >> (i * 8)) as u8));
 	prepend
@@ -120,11 +132,8 @@ fn to_keyed_vec(value: u32, mut prepend: Vec<u8>) -> Vec<u8> {
 
 /// Externalities: pinned to specific active address.
 pub trait Externalities {
-	/// Externalities error type.
-	type Error: Error;
-
 	/// Read storage of current contract being called.
-	fn storage(&self, key: &[u8]) -> Result<&[u8], Self::Error>;
+	fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError>;
 
 	/// Set storage of current contract being called (effective immediately).
 	fn set_storage(&mut self, key: Vec<u8>, value: Vec<u8>);
@@ -133,7 +142,7 @@ pub trait Externalities {
 	fn chain_id(&self) -> u64;
 
 	/// Get the current set of authorities from storage.
-	fn authorities(&self) -> Result<Vec<&[u8]>, Self::Error> {
+	fn authorities(&self) -> Result<Vec<&[u8]>, ExternalitiesError> {
 		(0..self.storage(b"con:aut:len")?.into_iter()
 				.rev()
 				.fold(0, |acc, &i| (acc << 8) + (i as u32)))
@@ -202,7 +211,7 @@ pub fn execute<B: backend::Backend, Exec: CodeExecutor>(
 #[cfg(test)]
 mod tests {
 	use std::collections::HashMap;
-	use super::{OverlayedChanges, Externalities};
+	use super::{OverlayedChanges, Externalities, ExternalitiesError};
 
 	#[test]
 	fn overlayed_storage_works() {
@@ -234,9 +243,7 @@ mod tests {
 		storage: HashMap<Vec<u8>, Vec<u8>>,
 	}
 	impl Externalities for TestExternalities {
-		type Error = u8;
-
-		fn storage(&self, key: &[u8]) -> Result<&[u8], Self::Error> {
+		fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError> {
 			Ok(self.storage.get(&key.to_vec()).map_or(&[] as &[u8], Vec::as_slice))
 		}
 
diff --git a/substrate/wasm-runtime/Cargo.lock b/substrate/wasm-runtime/Cargo.lock
index d134139a3c..15ccc67c64 100644
--- a/substrate/wasm-runtime/Cargo.lock
+++ b/substrate/wasm-runtime/Cargo.lock
@@ -13,11 +13,11 @@ version = "0.1.0"
 name = "runtime-polkadot"
 version = "0.1.0"
 dependencies = [
- "runtime-support 0.1.0",
+ "runtime-std 0.1.0",
 ]
 
 [[package]]
-name = "runtime-support"
+name = "runtime-std"
 version = "0.1.0"
 dependencies = [
  "pwasm-alloc 0.1.0",
@@ -28,6 +28,6 @@ dependencies = [
 name = "runtime-test"
 version = "0.1.0"
 dependencies = [
- "runtime-support 0.1.0",
+ "runtime-std 0.1.0",
 ]
 
diff --git a/substrate/wasm-runtime/build.sh b/substrate/wasm-runtime/build.sh
index c3030f99d3..83f46d5a04 100755
--- a/substrate/wasm-runtime/build.sh
+++ b/substrate/wasm-runtime/build.sh
@@ -1,7 +1,8 @@
 #!/bin/sh
+set -e
 
 cargo +nightly build --target=wasm32-unknown-unknown --release
-dirs=`find * -maxdepth 0 -type d | grep -v pwasm- | grep -v support`
+dirs=`find * -maxdepth 0 -type d | grep -v pwasm- | grep -v std`
 for i in $dirs
 do
 	if [[ -e $i/Cargo.toml ]]
diff --git a/substrate/wasm-runtime/polkadot/Cargo.toml b/substrate/wasm-runtime/polkadot/Cargo.toml
index ce2d9909a7..669ccac6fa 100644
--- a/substrate/wasm-runtime/polkadot/Cargo.toml
+++ b/substrate/wasm-runtime/polkadot/Cargo.toml
@@ -7,7 +7,7 @@ authors = ["Parity Technologies <admin@parity.io>"]
 crate-type = ["cdylib"]
 
 [dependencies]
-runtime-support = { path = "../support", version = "0.1" }
+runtime-std = { path = "../std", version = "0.1" }
 
 [features]
 default = ["without-std"]
diff --git a/substrate/wasm-runtime/polkadot/src/codec/endiansensitive.rs b/substrate/wasm-runtime/polkadot/src/codec/endiansensitive.rs
index c4978d5ce4..1b550edffa 100644
--- a/substrate/wasm-runtime/polkadot/src/codec/endiansensitive.rs
+++ b/substrate/wasm-runtime/polkadot/src/codec/endiansensitive.rs
@@ -17,7 +17,9 @@
 //! Endian manager.
 
 /// Trait to allow conversion to a know endian representation when sensitive.
-// note: the copy bound and static lifetimes are necessary for safety of `Slicable` blanket implementation.
+/// Types implementing this trait must have a size > 0.
+// note: the copy bound and static lifetimes are necessary for safety of `Slicable` blanket
+// implementation.
 pub trait EndianSensitive: Copy + 'static {
 	fn to_le(self) -> Self { self }
 	fn to_be(self) -> Self { self }
@@ -45,6 +47,9 @@ macro_rules! impl_non_endians {
 	)* }
 }
 
+// NOTE: See test to ensure correctness.
+impl EndianSensitive for bool {}
+
 impl_endians!(u16, u32, u64, usize, i16, i32, i64, isize);
 impl_non_endians!(u8, i8, [u8; 1], [u8; 2], [u8; 3], [u8; 4], [u8; 5], [u8; 6], [u8; 7], [u8; 8],
 	[u8; 10], [u8; 12], [u8; 14], [u8; 16], [u8; 20], [u8; 24], [u8; 28], [u8; 32], [u8; 40],
@@ -65,4 +70,12 @@ mod tests {
 		fn _takes_static<T: 'static>() { }
 		fn _takes_endian_sensitive<T: EndianSensitive>() { _takes_static::<T>() }
 	}
+
+	#[test]
+	fn bool_is_not_endian_sensitive() {
+		let b = true;
+		assert_eq!(b.to_be(), b.to_le());
+		let b = false;
+		assert_eq!(b.to_be(), b.to_le());
+	}
 }
diff --git a/substrate/wasm-runtime/polkadot/src/codec/joiner.rs b/substrate/wasm-runtime/polkadot/src/codec/joiner.rs
index 7fdb1e1645..a7a9f618eb 100644
--- a/substrate/wasm-runtime/polkadot/src/codec/joiner.rs
+++ b/substrate/wasm-runtime/polkadot/src/codec/joiner.rs
@@ -16,8 +16,8 @@
 
 //! Vec<u8> serialiser.
 
-use runtime_support::prelude::*;
-use slicable::Slicable;
+use runtime_std::prelude::*;
+use super::slicable::Slicable;
 
 /// Trait to allow itself to be serialised into a `Vec<u8>`
 pub trait Joiner {
diff --git a/substrate/wasm-runtime/polkadot/src/codec/keyedvec.rs b/substrate/wasm-runtime/polkadot/src/codec/keyedvec.rs
index 210606ab7c..2c55cb5648 100644
--- a/substrate/wasm-runtime/polkadot/src/codec/keyedvec.rs
+++ b/substrate/wasm-runtime/polkadot/src/codec/keyedvec.rs
@@ -16,8 +16,8 @@
 
 //! Serialiser and prepender.
 
-use runtime_support::prelude::*;
-use slicable::Slicable;
+use runtime_std::prelude::*;
+use super::slicable::Slicable;
 
 /// Trait to allow itselg to be serialised and prepended by a given slice.
 pub trait KeyedVec {
diff --git a/substrate/wasm-runtime/polkadot/src/codec/mod.rs b/substrate/wasm-runtime/polkadot/src/codec/mod.rs
index 7d9bc90c4f..94afc574c1 100644
--- a/substrate/wasm-runtime/polkadot/src/codec/mod.rs
+++ b/substrate/wasm-runtime/polkadot/src/codec/mod.rs
@@ -16,8 +16,14 @@
 
 //! Codec utils.
 
-pub mod endiansensitive;
-pub mod streamreader;
-pub mod joiner;
-pub mod slicable;
-pub mod keyedvec;
+mod endiansensitive;
+mod slicable;
+mod streamreader;
+mod joiner;
+mod keyedvec;
+
+pub use self::endiansensitive::EndianSensitive;
+pub use self::slicable::{Slicable, NonTrivialSlicable};
+pub use self::streamreader::StreamReader;
+pub use self::joiner::Joiner;
+pub use self::keyedvec::KeyedVec;
diff --git a/substrate/wasm-runtime/polkadot/src/codec/slicable.rs b/substrate/wasm-runtime/polkadot/src/codec/slicable.rs
index 40f8a532b7..0f1ef812a6 100644
--- a/substrate/wasm-runtime/polkadot/src/codec/slicable.rs
+++ b/substrate/wasm-runtime/polkadot/src/codec/slicable.rs
@@ -16,16 +16,18 @@
 
 //! Serialisation.
 
-use runtime_support::prelude::*;
-use runtime_support::{mem, slice};
-use joiner::Joiner;
-use endiansensitive::EndianSensitive;
+use runtime_std::prelude::*;
+use runtime_std::{mem, slice};
+use super::joiner::Joiner;
+use super::endiansensitive::EndianSensitive;
 
 /// Trait that allows zero-copy read/write of value-references to/from slices in LE format.
 pub trait Slicable: Sized {
 	fn from_slice(value: &[u8]) -> Option<Self> {
-		Self::set_as_slice(|out| if value.len() == out.len() {
-			out.copy_from_slice(&value);
+		Self::set_as_slice(&|out, offset| if value.len() >= out.len() + offset {
+			let value = &value[offset..];
+			let len = out.len();
+			out.copy_from_slice(&value[0..len]);
 			true
 		} else {
 			false
@@ -34,7 +36,7 @@ pub trait Slicable: Sized {
 	fn to_vec(&self) -> Vec<u8> {
 		self.as_slice_then(|s| s.to_vec())
 	}
-	fn set_as_slice<F: FnOnce(&mut [u8]) -> bool>(set_slice: F) -> Option<Self>;
+	fn set_as_slice<F: Fn(&mut [u8], usize) -> bool>(set_slice: &F) -> Option<Self>;
 	fn as_slice_then<R, F: FnOnce(&[u8]) -> R>(&self, f: F) -> R {
 		f(&self.to_vec())
 	}
@@ -45,14 +47,15 @@ pub trait Slicable: Sized {
 pub trait NonTrivialSlicable: Slicable {}
 
 impl<T: EndianSensitive> Slicable for T {
-	fn set_as_slice<F: FnOnce(&mut [u8]) -> bool>(fill_slice: F) -> Option<Self> {
+	fn set_as_slice<F: Fn(&mut [u8], usize) -> bool>(fill_slice: &F) -> Option<Self> {
 		let size = mem::size_of::<T>();
+		assert!(size > 0, "EndianSensitive can never be implemented for a zero-sized type.");
 		let mut result: T = unsafe { mem::zeroed() };
 		let result_slice = unsafe {
 			let ptr = &mut result as *mut _ as *mut u8;
 			slice::from_raw_parts_mut(ptr, size)
 		};
-		if fill_slice(result_slice) {
+		if fill_slice(result_slice, 0) {
 			Some(result.from_le())
 		} else {
 			None
@@ -60,6 +63,7 @@ impl<T: EndianSensitive> Slicable for T {
 	}
 	fn as_slice_then<R, F: FnOnce(&[u8]) -> R>(&self, f: F) -> R {
 		let size = mem::size_of::<Self>();
+		assert!(size > 0, "EndianSensitive can never be implemented for a zero-sized type.");
 		self.as_le_then(|le| {
 			let value_slice = unsafe {
 				let ptr = le as *const _ as *const u8;
@@ -77,8 +81,16 @@ impl Slicable for Vec<u8> {
 	fn from_slice(value: &[u8]) -> Option<Self> {
 		Some(value[4..].to_vec())
 	}
-	fn set_as_slice<F: FnOnce(&mut [u8]) -> bool>(_fill_slice: F) -> Option<Self> {
-		unimplemented!();
+	fn set_as_slice<F: Fn(&mut [u8], usize) -> bool>(fill_slice: &F) -> Option<Self> {
+		u32::set_as_slice(fill_slice).and_then(|len| {
+			let mut v = Vec::with_capacity(len as usize);
+			unsafe { v.set_len(len as usize); }
+			if fill_slice(&mut v, 4) {
+				Some(v)
+			} else {
+				None
+			}
+		})
 	}
 	fn to_vec(&self) -> Vec<u8> {
 		let mut r: Vec<u8> = Vec::new().join(&(self.len() as u32));
@@ -89,3 +101,48 @@ impl Slicable for Vec<u8> {
 		u32::from_slice(&data[0..4]).map(|i| (i + 4) as usize)
 	}
 }
+
+impl<T: Slicable> NonTrivialSlicable for Vec<T> where Vec<T>: Slicable {}
+
+impl<T: NonTrivialSlicable> Slicable for Vec<T> {
+	fn from_slice(value: &[u8]) -> Option<Self> {
+		let len = Self::size_of(&value[0..4])?;
+		let mut off = 4;
+		let mut r = Vec::new();
+		while off < len {
+			let element_len = T::size_of(&value[off..])?;
+			r.push(T::from_slice(&value[off..off + element_len])?);
+			off += element_len;
+		}
+		Some(r)
+	}
+
+	fn set_as_slice<F: Fn(&mut [u8], usize) -> bool>(_fill_slice: &F) -> Option<Self> {
+		unimplemented!();
+	}
+
+	fn to_vec(&self) -> Vec<u8> {
+		let vecs = self.iter().map(Slicable::to_vec).collect::<Vec<_>>();
+		let len = vecs.iter().fold(0, |mut a, v| {a += v.len(); a});
+		let mut r = Vec::new().join(&(len as u32));
+		vecs.iter().for_each(|v| r.extend_from_slice(v));
+		r
+	}
+
+	fn size_of(data: &[u8]) -> Option<usize> {
+		u32::from_slice(&data[0..4]).map(|i| (i + 4) as usize)
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+
+	#[test]
+	fn vec_is_slicable() {
+		let v = b"Hello world".to_vec();
+		v.as_slice_then(|ref slice|
+			assert_eq!(slice, &b"\x0b\0\0\0Hello world")
+		);
+	}
+}
diff --git a/substrate/wasm-runtime/polkadot/src/codec/streamreader.rs b/substrate/wasm-runtime/polkadot/src/codec/streamreader.rs
index 33056a5ac3..b745f8afd9 100644
--- a/substrate/wasm-runtime/polkadot/src/codec/streamreader.rs
+++ b/substrate/wasm-runtime/polkadot/src/codec/streamreader.rs
@@ -16,7 +16,7 @@
 
 //! Deserialiser.
 
-use slicable::Slicable;
+use super::slicable::Slicable;
 
 /// Simple deserialiser.
 pub struct StreamReader<'a> {
diff --git a/substrate/wasm-runtime/polkadot/src/lib.rs b/substrate/wasm-runtime/polkadot/src/lib.rs
index a08cc046d3..1eeff3c649 100644
--- a/substrate/wasm-runtime/polkadot/src/lib.rs
+++ b/substrate/wasm-runtime/polkadot/src/lib.rs
@@ -20,34 +20,32 @@
 #![cfg_attr(feature = "strict", deny(warnings))]
 
 #[macro_use]
-extern crate runtime_support;
+extern crate runtime_std;
 
-#[cfg(test)]
+#[cfg(feature = "with-std")]
 extern crate rustc_hex;
 
-mod codec;
+pub mod codec;
 #[macro_use]
-mod support;
-mod runtime;
-pub use codec::{endiansensitive, streamreader, joiner, slicable, keyedvec};
-pub use support::{primitives, function, environment, storable};
-#[cfg(test)]
-pub use support::{testing, statichex};
+pub mod support;
+pub mod primitives;
+pub mod runtime;
 
-use runtime_support::prelude::*;
-use slicable::Slicable;
+use runtime_std::prelude::*;
+use codec::Slicable;
 use primitives::{Block, UncheckedTransaction};
 
 /// Execute a block, with `input` being the canonical serialisation of the block. Returns the
 /// empty vector.
-pub fn execute_block(input: Vec<u8>) -> Vec<u8> {
-	runtime::system::execute_block(Block::from_slice(&input).unwrap());
+pub fn execute_block(input: &[u8]) -> Vec<u8> {
+	runtime::system::internal::execute_block(Block::from_slice(input).unwrap());
 	Vec::new()
 }
 
 /// Execute a given, serialised, transaction. Returns the empty vector.
-pub fn execute_transaction(input: Vec<u8>) -> Vec<u8> {
-	runtime::system::execute_transaction(&UncheckedTransaction::from_slice(&input).unwrap());
+pub fn execute_transaction(input: &[u8]) -> Vec<u8> {
+	let utx = UncheckedTransaction::from_slice(input).unwrap();
+	runtime::system::internal::execute_transaction(&utx);
 	Vec::new()
 }
 
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/block.rs b/substrate/wasm-runtime/polkadot/src/primitives/block.rs
new file mode 100644
index 0000000000..d33b51609c
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/block.rs
@@ -0,0 +1,58 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Block type.
+
+use runtime_std::prelude::*;
+use codec::{StreamReader, Joiner, Slicable, NonTrivialSlicable};
+use primitives::{Header, UncheckedTransaction};
+
+/// A Polkadot relay chain block.
+#[cfg_attr(feature = "with-std", derive(PartialEq, Debug))]
+pub struct Block {
+	/// The header of the block.
+	pub header: Header,
+	/// All transactions.
+	pub transactions: Vec<UncheckedTransaction>,
+}
+
+impl Slicable for Block {
+	fn from_slice(value: &[u8]) -> Option<Self> {
+		let mut reader = StreamReader::new(value);
+		Some(Block {
+			header: reader.read()?,
+			transactions: reader.read()?,
+		})
+	}
+
+	fn set_as_slice<F: Fn(&mut [u8], usize) -> bool>(_fill_slice: &F) -> Option<Self> {
+		unimplemented!();
+	}
+
+	fn to_vec(&self) -> Vec<u8> {
+		Vec::new()
+			.join(&self.header)
+			.join(&self.transactions)
+	}
+
+	fn size_of(data: &[u8]) -> Option<usize> {
+		let first_part = Header::size_of(data)?;
+		let second_part = <Vec<UncheckedTransaction>>::size_of(&data[first_part..])?;
+		Some(first_part + second_part)
+	}
+}
+
+impl NonTrivialSlicable for Block {}
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/digest.rs b/substrate/wasm-runtime/polkadot/src/primitives/digest.rs
new file mode 100644
index 0000000000..18107460b0
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/digest.rs
@@ -0,0 +1,27 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Digest type.
+
+use runtime_std::prelude::*;
+
+#[derive(Clone, Default)]
+#[cfg_attr(feature = "with-std", derive(PartialEq, Debug))]
+/// The digest of a block, useful for light-clients.
+pub struct Digest {
+	/// All logs that have happened in the block.
+	pub logs: Vec<Vec<u8>>,
+}
diff --git a/substrate/wasm-runtime/polkadot/src/support/function.rs b/substrate/wasm-runtime/polkadot/src/primitives/function.rs
similarity index 56%
rename from substrate/wasm-runtime/polkadot/src/support/function.rs
rename to substrate/wasm-runtime/polkadot/src/primitives/function.rs
index f4ee9c79e6..e906cdc718 100644
--- a/substrate/wasm-runtime/polkadot/src/support/function.rs
+++ b/substrate/wasm-runtime/polkadot/src/primitives/function.rs
@@ -17,30 +17,34 @@
 //! Function data: This describes a function that can be called from an external transaction.
 
 use primitives::AccountID;
-use streamreader::StreamReader;
-use runtime::{staking, session, timestamp};
+use codec::StreamReader;
+use runtime::{staking, session, timestamp, governance};
 
-/// The functions that a transaction can call (and be dispatched to).
-#[cfg_attr(test, derive(PartialEq, Debug))]
+/// Public functions that can be dispatched to.
 #[derive(Clone, Copy)]
+#[cfg_attr(feature = "with-std", derive(PartialEq, Debug))]
+#[repr(u8)]
 pub enum Function {
-	StakingStake,
-	StakingUnstake,
-	StakingTransfer,
-	SessionSetKey,
-	TimestampSet,
+	StakingStake = 0,
+	StakingUnstake = 1,
+	StakingTransfer = 2,
+	SessionSetKey = 3,
+	TimestampSet = 4,
+	GovernancePropose = 5,
+	GovernanceApprove = 6,
 }
 
 impl Function {
 	/// Derive `Some` value from a `u8`, or `None` if it's invalid.
 	pub fn from_u8(value: u8) -> Option<Function> {
-		match value {
-			x if x == Function::StakingStake as u8 => Some(Function::StakingStake),
-			x if x == Function::StakingUnstake as u8 => Some(Function::StakingUnstake),
-			x if x == Function::StakingTransfer as u8 => Some(Function::StakingTransfer),
-			x if x == Function::SessionSetKey as u8 => Some(Function::SessionSetKey),
-			x if x == Function::TimestampSet as u8 => Some(Function::TimestampSet),
-			_ => None,
+		use self::*;
+		let functions = [Function::StakingStake, Function::StakingUnstake,
+			Function::StakingTransfer, Function::SessionSetKey, Function::TimestampSet,
+			Function::GovernancePropose, Function::GovernanceApprove];
+		if (value as usize) < functions.len() {
+			Some(functions[value as usize])
+		} else {
+			None
 		}
 	}
 }
@@ -51,23 +55,31 @@ impl Function {
 		let mut params = StreamReader::new(data);
 		match *self {
 			Function::StakingStake => {
-				staking::stake(transactor);
+				staking::public::stake(transactor);
 			}
 			Function::StakingUnstake => {
-				staking::unstake(transactor);
+				staking::public::unstake(transactor);
 			}
 			Function::StakingTransfer => {
 				let dest = params.read().unwrap();
 				let value = params.read().unwrap();
-				staking::transfer(transactor, &dest, value);
+				staking::public::transfer(transactor, &dest, value);
 			}
 			Function::SessionSetKey => {
 				let session = params.read().unwrap();
-				session::set_key(transactor, &session);
+				session::public::set_key(transactor, &session);
 			}
 			Function::TimestampSet => {
 				let t = params.read().unwrap();
-				timestamp::set(t);
+				timestamp::public::set(t);
+			}
+			Function::GovernancePropose => {
+				let proposal = params.read().unwrap();
+				governance::public::propose(transactor, &proposal);
+			}
+			Function::GovernanceApprove => {
+				let era_index = params.read().unwrap();
+				governance::public::approve(transactor, era_index);
 			}
 		}
 	}
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/header.rs b/substrate/wasm-runtime/polkadot/src/primitives/header.rs
new file mode 100644
index 0000000000..c97d5ebf29
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/header.rs
@@ -0,0 +1,72 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Block header type.
+
+use runtime_std::prelude::*;
+use codec::{StreamReader, Joiner, Slicable, NonTrivialSlicable};
+use runtime_std::mem;
+use primitives::{BlockNumber, Hash, Digest};
+
+#[derive(Clone)]
+#[cfg_attr(feature = "with-std", derive(PartialEq, Debug))]
+/// The header for a block.
+pub struct Header {
+	/// The parent block's "hash" (actually the Blake2-256 hash of its serialised header).
+	pub parent_hash: Hash,
+	/// The block's number (how many ancestors does it have?).
+	pub number: BlockNumber,
+	/// The root of the trie that represents this block's final storage map.
+	pub state_root: Hash,
+	/// The root of the trie that represents this block's transactions, indexed by a 32-bit integer.
+	pub transaction_root: Hash,
+	/// The digest for this block.
+	pub digest: Digest,
+}
+
+impl Slicable for Header {
+	fn from_slice(value: &[u8]) -> Option<Self> {
+		let mut reader = StreamReader::new(value);
+		Some(Header {
+			parent_hash: reader.read()?,
+			number: reader.read()?,
+			state_root: reader.read()?,
+			transaction_root: reader.read()?,
+			digest: Digest { logs: reader.read()?, },
+		})
+	}
+
+	fn set_as_slice<F: Fn(&mut [u8], usize) -> bool>(_fill_slice: &F) -> Option<Self> {
+		unimplemented!();
+	}
+
+	fn to_vec(&self) -> Vec<u8> {
+		Vec::new()
+			.join(&self.parent_hash)
+			.join(&self.number)
+			.join(&self.state_root)
+			.join(&self.transaction_root)
+			.join(&self.digest.logs)
+	}
+
+	fn size_of(data: &[u8]) -> Option<usize> {
+		let first_part = mem::size_of::<Hash>() + mem::size_of::<BlockNumber>() + mem::size_of::<Hash>() + mem::size_of::<Hash>();
+		let second_part = <Vec<Vec<u8>>>::size_of(&data[first_part..])?;
+		Some(first_part + second_part)
+	}
+}
+
+impl NonTrivialSlicable for Header {}
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/misc.rs b/substrate/wasm-runtime/polkadot/src/primitives/misc.rs
new file mode 100644
index 0000000000..2d6954f9e7
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/misc.rs
@@ -0,0 +1,41 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Miscellaneous small types.
+
+/// The Ed25519 pubkey that identifies an account.
+pub type AccountID = [u8; 32];
+
+/// Virtual account ID that represents the idea of a dispatch/statement being signed by everybody
+/// (who matters). Essentially this means that a majority of validators have decided it is
+/// "correct".
+pub const EVERYBODY: AccountID = [255u8; 32];
+
+/// The Ed25519 pub key of an session that belongs to an authority. This is used as what the
+/// external environment/consensus algorithm calls an "authority".
+pub type SessionKey = AccountID;
+
+/// Indentifier for a chain.
+pub type ChainID = u64;
+
+/// Index of a block in the chain.
+pub type BlockNumber = u64;
+
+/// Index of a transaction.
+pub type TxOrder = u64;
+
+/// A hash of some data.
+pub type Hash = [u8; 32];
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/mod.rs b/substrate/wasm-runtime/polkadot/src/primitives/mod.rs
new file mode 100644
index 0000000000..51ce3d121a
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/mod.rs
@@ -0,0 +1,38 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Primitive types for the runtime.
+
+mod misc;
+mod proposal;
+mod function;
+mod digest;
+mod header;
+mod transaction;
+mod uncheckedtransaction;
+mod block;
+
+#[cfg(test)]
+mod tests;
+
+pub use self::misc::{AccountID, EVERYBODY, SessionKey, ChainID, BlockNumber, TxOrder, Hash};
+pub use self::proposal::{Proposal, InternalFunction};
+pub use self::function::Function;
+pub use self::digest::Digest;
+pub use self::header::Header;
+pub use self::transaction::Transaction;
+pub use self::uncheckedtransaction::UncheckedTransaction;
+pub use self::block::Block;
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/proposal.rs b/substrate/wasm-runtime/polkadot/src/primitives/proposal.rs
new file mode 100644
index 0000000000..1b8aa6b13e
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/proposal.rs
@@ -0,0 +1,137 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Proposal: This describes a combination of a function ID and data that can be used to call into
+//! an internal function.
+
+use runtime_std::prelude::*;
+use runtime_std::mem;
+use codec::{Slicable, Joiner, StreamReader};
+use runtime::{system, governance, staking, session};
+
+/// Internal functions that can be dispatched to.
+#[derive(Clone, Copy)]
+#[cfg_attr(feature = "with-std", derive(PartialEq, Debug))]
+#[repr(u8)]
+pub enum InternalFunction {
+	SystemSetCode = 0,
+	StakingSetSessionsPerEra = 1,
+	StakingSetBondingDuration = 2,
+	StakingSetValidatorCount = 3,
+	GovernanceSetApprovalPpmRequired = 4,
+	SessionSetLength = 5,
+}
+
+impl InternalFunction {
+	/// Derive `Some` value from a `u8`, or `None` if it's invalid.
+	pub fn from_u8(value: u8) -> Option<InternalFunction> {
+		use self::*;
+		let functions = [
+			InternalFunction::SystemSetCode,
+			InternalFunction::StakingSetSessionsPerEra,
+			InternalFunction::StakingSetBondingDuration,
+			InternalFunction::StakingSetValidatorCount,
+			InternalFunction::GovernanceSetApprovalPpmRequired,
+			InternalFunction::SessionSetLength
+		];
+		if (value as usize) < functions.len() {
+			Some(functions[value as usize])
+		} else {
+			None
+		}
+	}
+}
+
+/// An internal function.
+#[cfg_attr(feature = "with-std", derive(PartialEq, Debug))]
+pub struct Proposal {
+	/// The priviledged function to call.
+	pub function: InternalFunction,
+	/// The serialised data to call it with.
+	pub input_data: Vec<u8>,
+}
+
+impl Slicable for Proposal {
+	fn set_as_slice<F: Fn(&mut[u8], usize) -> bool>(fill_slice: &F) -> Option<Self> {
+		Some(Proposal {
+			function: InternalFunction::from_u8(Slicable::set_as_slice(fill_slice)?)?,
+			input_data: Slicable::set_as_slice(&|s, o| fill_slice(s, o + 1))?,
+		})
+	}
+
+	fn to_vec(&self) -> Vec<u8> {
+		Vec::new()
+			.join(&(self.function as u8))
+			.join(&self.input_data)
+	}
+
+	fn size_of(data: &[u8]) -> Option<usize> {
+		let first_part = mem::size_of::<u8>();
+		let second_part = <Vec<u8>>::size_of(&data[first_part..])?;
+		Some(first_part + second_part)
+	}
+}
+
+impl Proposal {
+	pub fn enact(&self) {
+		let mut params = StreamReader::new(&self.input_data);
+		match self.function {
+			InternalFunction::SystemSetCode => {
+				let code: Vec<u8> = params.read().unwrap();
+				system::privileged::set_code(&code);
+			}
+			InternalFunction::StakingSetSessionsPerEra => {
+				let value = params.read().unwrap();
+				staking::privileged::set_sessions_per_era(value);
+			}
+			InternalFunction::StakingSetBondingDuration => {
+				let value = params.read().unwrap();
+				staking::privileged::set_bonding_duration(value);
+			}
+			InternalFunction::StakingSetValidatorCount => {
+				let value = params.read().unwrap();
+				staking::privileged::set_validator_count(value);
+			}
+			InternalFunction::GovernanceSetApprovalPpmRequired => {
+				let value = params.read().unwrap();
+				governance::privileged::set_approval_ppm_required(value);
+			}
+			InternalFunction::SessionSetLength => {
+				let value = params.read().unwrap();
+				session::privileged::set_length(value);
+			}
+		}
+	}
+}
+
+#[cfg(test)]
+mod test {
+	use super::*;
+	use support::StaticHexInto;
+
+	#[test]
+	fn slicing_should_work() {
+		let p = Proposal {
+			function: InternalFunction::SystemSetCode,
+			input_data: b"Hello world".to_vec(),
+		};
+		let v = p.to_vec();
+		assert_eq!(v, "000b00000048656c6c6f20776f726c64".convert::<Vec<u8>>());
+
+		let o = Proposal::from_slice(&v).unwrap();
+		assert_eq!(p, o);
+	}
+}
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/tests.rs b/substrate/wasm-runtime/polkadot/src/primitives/tests.rs
new file mode 100644
index 0000000000..fdb600a5bb
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/tests.rs
@@ -0,0 +1,241 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Tests.
+
+use super::*;
+use runtime_std::prelude::*;
+use codec::{Joiner, Slicable};
+use primitives::Function;
+
+#[test]
+fn serialise_transaction_works() {
+	let one: AccountID = [1u8; 32];
+	let two: AccountID = [2u8; 32];
+	let tx = Transaction {
+		signed: one.clone(),
+		nonce: 69,
+		function: Function::StakingTransfer,
+		input_data: Vec::new().join(&two).join(&69u64),
+	};
+	let serialised = tx.to_vec();
+	assert_eq!(serialised, vec![
+		1u8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+		69, 0, 0, 0, 0, 0, 0, 0,
+		2,
+		40, 0, 0, 0,
+			2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+			69, 0, 0, 0, 0, 0, 0, 0
+	]);
+}
+
+#[test]
+fn deserialise_transaction_works() {
+	let one: AccountID = [1u8; 32];
+	let two: AccountID = [2u8; 32];
+	let tx = Transaction {
+		signed: one.clone(),
+		nonce: 69,
+		function: Function::StakingTransfer,
+		input_data: Vec::new().join(&two).join(&69u64),
+	};
+	let data = [
+		1u8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+		69, 0, 0, 0, 0, 0, 0, 0,
+		2,
+		40, 0, 0, 0,
+			2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+			69, 0, 0, 0, 0, 0, 0, 0
+	];
+	let deserialised = Transaction::from_slice(&data).unwrap();
+	assert_eq!(deserialised, tx);
+}
+
+#[test]
+fn serialise_header_works() {
+	let h = Header {
+		parent_hash: [4u8; 32],
+		number: 42,
+		state_root: [5u8; 32],
+		transaction_root: [6u8; 32],
+		digest: Digest { logs: vec![ b"one log".to_vec(), b"another log".to_vec() ], },
+	};
+	let serialised = h.to_vec();
+	assert_eq!(serialised, vec![
+		4u8, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+		42, 0, 0, 0, 0, 0, 0, 0,
+		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		26, 0, 0, 0,
+			7, 0, 0, 0,
+				111, 110, 101, 32, 108, 111, 103,
+			11, 0, 0, 0,
+				97, 110, 111, 116, 104, 101, 114, 32, 108, 111, 103
+	]);
+}
+
+#[test]
+fn deserialise_header_works() {
+	let h = Header {
+		parent_hash: [4u8; 32],
+		number: 42,
+		state_root: [5u8; 32],
+		transaction_root: [6u8; 32],
+		digest: Digest { logs: vec![ b"one log".to_vec(), b"another log".to_vec() ], },
+	};
+	let data = [
+		4u8, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+		42, 0, 0, 0, 0, 0, 0, 0,
+		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		26, 0, 0, 0,
+			7, 0, 0, 0,
+				111, 110, 101, 32, 108, 111, 103,
+			11, 0, 0, 0,
+				97, 110, 111, 116, 104, 101, 114, 32, 108, 111, 103
+	];
+	let deserialised = Header::from_slice(&data).unwrap();
+	assert_eq!(deserialised, h);
+}
+
+#[test]
+fn serialise_block_works() {
+	let one: AccountID = [1u8; 32];
+	let two: AccountID = [2u8; 32];
+	let tx1 = UncheckedTransaction {
+		transaction: Transaction {
+			signed: one.clone(),
+			nonce: 69,
+			function: Function::StakingTransfer,
+			input_data: Vec::new().join(&two).join(&69u64),
+		},
+		signature: [1u8; 64],
+	};
+	let tx2 = UncheckedTransaction {
+		transaction: Transaction {
+			signed: two.clone(),
+			nonce: 42,
+			function: Function::StakingStake,
+			input_data: Vec::new(),
+		},
+		signature: [2u8; 64],
+	};
+	let h = Header {
+		parent_hash: [4u8; 32],
+		number: 42,
+		state_root: [5u8; 32],
+		transaction_root: [6u8; 32],
+		digest: Digest { logs: vec![ b"one log".to_vec(), b"another log".to_vec() ], },
+	};
+	let b = Block {
+		header: h,
+		transactions: vec![tx1, tx2],
+	};
+	let serialised = b.to_vec();
+	assert_eq!(serialised, vec![
+		// header
+		4u8, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+		42, 0, 0, 0, 0, 0, 0, 0,
+		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		26, 0, 0, 0,
+			7, 0, 0, 0,
+				111, 110, 101, 32, 108, 111, 103,
+			11, 0, 0, 0,
+				97, 110, 111, 116, 104, 101, 114, 32, 108, 111, 103,
+		// transactions
+		2, 1, 0, 0,
+			// tx1
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+			69, 0, 0, 0, 0, 0, 0, 0,
+			2,
+			40, 0, 0, 0,
+				2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+				69, 0, 0, 0, 0, 0, 0, 0,
+			// tx2
+			2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+			2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+			42, 0, 0, 0, 0, 0, 0, 0,
+			0,
+			0, 0, 0, 0
+	]);
+}
+
+#[test]
+fn deserialise_block_works() {
+	let one: AccountID = [1u8; 32];
+	let two: AccountID = [2u8; 32];
+	let tx1 = UncheckedTransaction {
+		transaction: Transaction {
+			signed: one.clone(),
+			nonce: 69,
+			function: Function::StakingTransfer,
+			input_data: Vec::new().join(&two).join(&69u64),
+		},
+		signature: [1u8; 64],
+	};
+	let tx2 = UncheckedTransaction {
+		transaction: Transaction {
+			signed: two.clone(),
+			nonce: 42,
+			function: Function::StakingStake,
+			input_data: Vec::new(),
+		},
+		signature: [2u8; 64],
+	};
+	let h = Header {
+		parent_hash: [4u8; 32],
+		number: 42,
+		state_root: [5u8; 32],
+		transaction_root: [6u8; 32],
+		digest: Digest { logs: vec![ b"one log".to_vec(), b"another log".to_vec() ], },
+	};
+	let b = Block {
+		header: h,
+		transactions: vec![tx1, tx2],
+	};
+	let data = [
+		// header
+		4u8, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+		42, 0, 0, 0, 0, 0, 0, 0,
+		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+		26, 0, 0, 0,
+			7, 0, 0, 0,
+				111, 110, 101, 32, 108, 111, 103,
+			11, 0, 0, 0,
+				97, 110, 111, 116, 104, 101, 114, 32, 108, 111, 103,
+		// transactions
+		2, 1, 0, 0,
+			// tx1
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+			69, 0, 0, 0, 0, 0, 0, 0,
+			2,
+			40, 0, 0, 0,
+				2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+				69, 0, 0, 0, 0, 0, 0, 0,
+			// tx2
+			2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+			2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+			42, 0, 0, 0, 0, 0, 0, 0,
+			0,
+			0, 0, 0, 0
+	];
+	let deserialised = Block::from_slice(&data).unwrap();
+	assert_eq!(deserialised, b);
+}
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/transaction.rs b/substrate/wasm-runtime/polkadot/src/primitives/transaction.rs
new file mode 100644
index 0000000000..9c72e31d34
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/transaction.rs
@@ -0,0 +1,67 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Transaction type.
+
+use runtime_std::prelude::*;
+use codec::{StreamReader, Joiner, Slicable, NonTrivialSlicable};
+use primitives::{AccountID, TxOrder, Function};
+use runtime_std::mem;
+
+/// A vetted and verified transaction from the external world.
+#[cfg_attr(feature = "with-std", derive(PartialEq, Debug))]
+pub struct Transaction {
+	/// Who signed it (note this is not a signature).
+	pub signed: AccountID,
+	/// The number of transactions have come before from the same signer.
+	pub nonce: TxOrder,
+	/// The function that should be called.
+	pub function: Function,
+	/// Serialised input data to the function.
+	pub input_data: Vec<u8>,
+}
+
+impl Slicable for Transaction {
+	fn from_slice(value: &[u8]) -> Option<Self> {
+		let mut reader = StreamReader::new(value);
+		Some(Transaction {
+			signed: reader.read()?,
+			nonce: reader.read()?,
+			function: Function::from_u8(reader.read()?)?,
+			input_data: reader.read()?,
+		})
+	}
+
+	fn set_as_slice<F: Fn(&mut [u8], usize) -> bool>(_fill_slice: &F) -> Option<Self> {
+		unimplemented!();
+	}
+
+	fn to_vec(&self) -> Vec<u8> {
+		Vec::new()
+			.join(&self.signed)
+			.join(&self.nonce)
+			.join(&(self.function as u8))
+			.join(&self.input_data)
+	}
+
+	fn size_of(data: &[u8]) -> Option<usize> {
+		let first_part = mem::size_of::<AccountID>() + mem::size_of::<TxOrder>() + mem::size_of::<u8>();
+		let second_part = <Vec<u8>>::size_of(&data[first_part..])?;
+		Some(first_part + second_part)
+	}
+}
+
+impl NonTrivialSlicable for Transaction {}
diff --git a/substrate/wasm-runtime/polkadot/src/primitives/uncheckedtransaction.rs b/substrate/wasm-runtime/polkadot/src/primitives/uncheckedtransaction.rs
new file mode 100644
index 0000000000..ec14befb55
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/primitives/uncheckedtransaction.rs
@@ -0,0 +1,83 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Unchecked Transaction type.
+
+use runtime_std::{mem, ed25519_verify};
+use runtime_std::prelude::*;
+use codec::{Slicable, NonTrivialSlicable, StreamReader, Joiner};
+use primitives::Transaction;
+
+#[cfg(feature = "with-std")]
+use std::fmt;
+
+/// A transactions right from the external world. Unchecked.
+pub struct UncheckedTransaction {
+	/// The actual transaction information.
+	pub transaction: Transaction,
+	/// The signature; should be an Ed25519 signature applied to the serialised `transaction` field.
+	pub signature: [u8; 64],
+}
+
+impl UncheckedTransaction {
+	/// Verify the signature.
+	pub fn ed25519_verify(&self) -> bool {
+		let msg = self.transaction.to_vec();
+		ed25519_verify(&self.signature, &msg, &self.transaction.signed)
+	}
+}
+
+#[cfg(feature = "with-std")]
+impl PartialEq for UncheckedTransaction {
+	fn eq(&self, other: &Self) -> bool {
+		self.signature.iter().eq(other.signature.iter()) && self.transaction == other.transaction
+	}
+}
+
+#[cfg(feature = "with-std")]
+impl fmt::Debug for UncheckedTransaction {
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+		write!(f, "UncheckedTransaction({:?})", self.transaction)
+	}
+}
+
+impl Slicable for UncheckedTransaction {
+	fn from_slice(value: &[u8]) -> Option<Self> {
+		let mut reader = StreamReader::new(value);
+		Some(UncheckedTransaction {
+			signature: reader.read()?,
+			transaction: reader.read()?,
+		})
+	}
+
+	fn set_as_slice<F: Fn(&mut [u8], usize) -> bool>(_fill_slice: &F) -> Option<Self> {
+		unimplemented!();
+	}
+
+	fn to_vec(&self) -> Vec<u8> {
+		Vec::new()
+			.join(&self.signature)
+			.join(&self.transaction)
+	}
+
+	fn size_of(data: &[u8]) -> Option<usize> {
+		let first_part = mem::size_of::<[u8; 64]>();
+		let second_part = <Transaction>::size_of(&data[first_part..])?;
+		Some(first_part + second_part)
+	}
+}
+
+impl NonTrivialSlicable for UncheckedTransaction {}
diff --git a/substrate/wasm-runtime/polkadot/src/runtime/consensus.rs b/substrate/wasm-runtime/polkadot/src/runtime/consensus.rs
index 689fdca21e..51666666cf 100644
--- a/substrate/wasm-runtime/polkadot/src/runtime/consensus.rs
+++ b/substrate/wasm-runtime/polkadot/src/runtime/consensus.rs
@@ -16,8 +16,8 @@
 
 //! Conensus module for runtime; manages the authority set ready for the native code.
 
-use runtime_support::prelude::*;
-use storable::StorageVec;
+use runtime_std::prelude::*;
+use support::StorageVec;
 use primitives::SessionKey;
 
 struct AuthorityStorageVec {}
@@ -31,14 +31,18 @@ pub fn authorities() -> Vec<SessionKey> {
 	AuthorityStorageVec::items()
 }
 
-/// Set the current set of authorities' session keys.
-///
-/// Called by `next_session` only.
-pub fn set_authorities(authorities: &[SessionKey]) {
-	AuthorityStorageVec::set_items(authorities);
-}
+pub mod internal {
+	use super::*;
 
-/// Set a single authority by index.
-pub fn set_authority(index: u32, key: &SessionKey) {
-	AuthorityStorageVec::set_item(index, key);
+	/// Set the current set of authorities' session keys.
+	///
+	/// Called by `next_session` only.
+	pub fn set_authorities(authorities: &[SessionKey]) {
+		AuthorityStorageVec::set_items(authorities);
+	}
+
+	/// Set a single authority by index.
+	pub fn set_authority(index: u32, key: &SessionKey) {
+		AuthorityStorageVec::set_item(index, key);
+	}
 }
diff --git a/substrate/wasm-runtime/polkadot/src/runtime/governance.rs b/substrate/wasm-runtime/polkadot/src/runtime/governance.rs
new file mode 100644
index 0000000000..4f7f6d8688
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/runtime/governance.rs
@@ -0,0 +1,366 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Governance system: Handles administration and dispatch of sensitive operations including
+//! setting new code, minting new tokens and changing parameters.
+//!
+//! For now this is limited to a simple qualified majority vote (whose parameter is retrieved from
+//! storage) between validators. A single vote may be proposed per era, and at most one approval
+//! vote may be cast by each validator. The tally is maintained through a simple tag in storage for
+//! each validator that has approved.
+//!
+//! At the end of the era, all validators approvals are tallied and if there are sufficient to pass
+//! the proposal then it is enacted. All items in storage concerning the proposal are reset.
+
+use runtime_std::prelude::*;
+use codec::KeyedVec;
+use support::storage;
+use primitives::{AccountID, Hash, BlockNumber, Proposal};
+use runtime::{staking, system, session};
+
+const APPROVALS_REQUIRED: &[u8] = b"gov:apr";
+const CURRENT_PROPOSAL: &[u8] = b"gov:pro";
+const APPROVAL_OF: &[u8] = b"gov:app:";
+
+/// The proportion of validators required for a propsal to be approved measured as the number out
+/// of 1000.
+pub fn approval_ppm_required() -> u32 {
+	storage::get_or(APPROVALS_REQUIRED, 1000)
+}
+
+/// The number of concrete validator approvals required for a proposal to pass.
+pub fn approvals_required() -> u32 {
+	approval_ppm_required() * session::validator_count() as u32 / 1000
+}
+
+pub mod public {
+	use super::*;
+
+	/// Propose a sensitive action to be taken. Any action that is enactable by `Proposal` is valid.
+	/// Proposal is by the `transactor` and will automatically count as an approval. Transactor must
+	/// be a current validator. It is illegal to propose when there is already a proposal in effect.
+	pub fn propose(validator: &AccountID, proposal: &Proposal) {
+		if storage::exists(CURRENT_PROPOSAL) {
+			panic!("there may only be one proposal per era.");
+		}
+		storage::put(CURRENT_PROPOSAL, proposal);
+		approve(validator, staking::current_era());
+	}
+
+	/// Approve the current era's proposal. Transactor must be a validator. This may not be done more
+	/// than once for any validator in an era.
+	pub fn approve(validator: &AccountID, era_index: BlockNumber) {
+		if era_index != staking::current_era() {
+			panic!("approval vote applied on non-current era.")
+		}
+		if !storage::exists(CURRENT_PROPOSAL) {
+			panic!("there must be a proposal in order to approve.");
+		}
+		if session::validators().into_iter().position(|v| &v == validator).is_none() {
+			panic!("transactor must be a validator to approve.");
+		}
+		let key = validator.to_keyed_vec(APPROVAL_OF);
+		if storage::exists(&key) {
+			panic!("transactor may not approve a proposal twice in one era.");
+		}
+		storage::put(&key, &true);
+	}
+}
+
+pub mod privileged {
+	use super::*;
+
+	/// Set the proportion of validators that must approve for a proposal to be enacted at the end of
+	/// its era. The value, `ppm`, is measured as a fraction of 1000 rounded down to the nearest whole
+	/// validator. `1000` would require the approval of all validators; `667` would require two-thirds
+	/// (or there abouts) of validators.
+	pub fn set_approval_ppm_required(ppm: u32) {
+		storage::put(APPROVALS_REQUIRED, &ppm);
+	}
+}
+
+pub mod internal {
+	use super::*;
+
+	/// Current era is ending; we should finish up any proposals.
+	pub fn end_of_an_era() {
+		// tally up votes for the current proposal, if any. enact if there are sufficient approvals.
+		if let Some(proposal) = storage::take::<Proposal>(CURRENT_PROPOSAL) {
+			let approvals_required = approvals_required();
+			let approved = session::validators().into_iter()
+				.filter_map(|v| storage::take::<bool>(&v.to_keyed_vec(APPROVAL_OF)))
+				.take(approvals_required as usize)
+				.count() as u32;
+			if approved == approvals_required {
+				proposal.enact();
+			}
+		}
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use runtime_std::{with_externalities, twox_128};
+	use codec::{KeyedVec, Joiner};
+	use support::{one, two, TestExternalities, with_env};
+	use primitives::{AccountID, InternalFunction};
+	use runtime::{staking, session};
+
+	fn new_test_ext() -> TestExternalities {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+
+		TestExternalities { storage: map![
+			twox_128(APPROVALS_REQUIRED).to_vec() => vec![].join(&667u32),
+			twox_128(b"ses:len").to_vec() => vec![].join(&1u64),
+			twox_128(b"ses:val:len").to_vec() => vec![].join(&3u32),
+			twox_128(&0u32.to_keyed_vec(b"ses:val:")).to_vec() => one.to_vec(),
+			twox_128(&1u32.to_keyed_vec(b"ses:val:")).to_vec() => two.to_vec(),
+			twox_128(&2u32.to_keyed_vec(b"ses:val:")).to_vec() => three.to_vec(),
+			twox_128(b"sta:wil:len").to_vec() => vec![].join(&3u32),
+			twox_128(&0u32.to_keyed_vec(b"sta:wil:")).to_vec() => one.to_vec(),
+			twox_128(&1u32.to_keyed_vec(b"sta:wil:")).to_vec() => two.to_vec(),
+			twox_128(&2u32.to_keyed_vec(b"sta:wil:")).to_vec() => three.to_vec(),
+			twox_128(b"sta:spe").to_vec() => vec![].join(&1u64),
+			twox_128(b"sta:vac").to_vec() => vec![].join(&3u64),
+			twox_128(b"sta:era").to_vec() => vec![].join(&1u64)
+		], }
+	}
+
+	#[test]
+	fn majority_voting_should_work() {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+		let mut t = new_test_ext();
+
+		with_externalities(&mut t, || {
+			assert_eq!(staking::era_length(), 1u64);
+			assert_eq!(staking::current_era(), 1u64);
+			assert_eq!(session::validator_count(), 3usize);
+			assert_eq!(session::validators(), vec![one.clone(), two.clone(), three.clone()]);
+			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
+
+			// Block 1: Make proposal. Approve it. Era length changes.
+			with_env(|e| e.block_number = 1);
+			public::propose(&one, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			public::approve(&two, 1);
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 2);
+		});
+	}
+
+	#[test]
+	fn majority_voting_should_work_after_unsuccessful_previous() {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+		let mut t = new_test_ext();
+
+		with_externalities(&mut t, || {
+			assert_eq!(staking::era_length(), 1u64);
+			assert_eq!(staking::current_era(), 1u64);
+			assert_eq!(session::validator_count(), 3usize);
+			assert_eq!(session::validators(), vec![one.clone(), two.clone(), three.clone()]);
+			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
+
+			// Block 1: Make proposal. Fail it.
+			with_env(|e| e.block_number = 1);
+			public::propose(&one, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 1);
+
+			// Block 2: Make proposal. Approve it. It should change era length.
+			with_env(|e| e.block_number = 2);
+			public::propose(&one, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			public::approve(&two, 2);
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 2);
+		});
+	}
+
+	#[test]
+	fn minority_voting_should_not_succeed() {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+		let mut t = new_test_ext();
+
+		with_externalities(&mut t, || {
+			assert_eq!(staking::era_length(), 1u64);
+			assert_eq!(staking::current_era(), 1u64);
+			assert_eq!(session::validator_count(), 3usize);
+			assert_eq!(session::validators(), vec![one.clone(), two.clone(), three.clone()]);
+			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
+
+			// Block 1: Make proposal. Will have only 1 vote. No change.
+			with_env(|e| e.block_number = 1);
+			public::propose(&one, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 1);
+		});
+	}
+
+	#[test]
+	#[should_panic]
+	fn old_voting_should_be_illegal() {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+		let mut t = new_test_ext();
+
+		with_externalities(&mut t, || {
+			assert_eq!(staking::era_length(), 1u64);
+			assert_eq!(staking::current_era(), 1u64);
+			assert_eq!(session::validator_count(), 3usize);
+			assert_eq!(session::validators(), vec![one.clone(), two.clone(), three.clone()]);
+			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
+
+			// Block 1: Make proposal. Will have only 1 vote. No change.
+			with_env(|e| e.block_number = 1);
+			public::propose(&one, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			public::approve(&two, 0);
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 1);
+		});
+	}
+
+	#[test]
+	#[should_panic]
+	fn double_voting_should_be_illegal() {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+		let mut t = new_test_ext();
+
+		with_externalities(&mut t, || {
+			assert_eq!(staking::era_length(), 1u64);
+			assert_eq!(staking::current_era(), 1u64);
+			assert_eq!(session::validator_count(), 3usize);
+			assert_eq!(session::validators(), vec![one.clone(), two.clone(), three.clone()]);
+			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
+
+			// Block 1: Make proposal. Will have only 1 vote. No change.
+			with_env(|e| e.block_number = 1);
+			public::propose(&one, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			public::approve(&two, 1);
+			public::approve(&two, 1);
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 1);
+		});
+	}
+
+	#[test]
+	#[should_panic]
+	fn over_proposing_should_be_illegal() {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+		let mut t = new_test_ext();
+
+		with_externalities(&mut t, || {
+			assert_eq!(staking::era_length(), 1u64);
+			assert_eq!(staking::current_era(), 1u64);
+			assert_eq!(session::validator_count(), 3usize);
+			assert_eq!(session::validators(), vec![one.clone(), two.clone(), three.clone()]);
+			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
+
+			// Block 1: Make proposal. Will have only 1 vote. No change.
+			with_env(|e| e.block_number = 1);
+			public::propose(&one, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			public::propose(&two, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 1);
+		});
+	}
+
+	#[test]
+	#[should_panic]
+	fn approving_without_proposal_should_be_illegal() {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+		let mut t = new_test_ext();
+
+		with_externalities(&mut t, || {
+			assert_eq!(staking::era_length(), 1u64);
+			assert_eq!(staking::current_era(), 1u64);
+			assert_eq!(session::validator_count(), 3usize);
+			assert_eq!(session::validators(), vec![one.clone(), two.clone(), three.clone()]);
+			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
+
+			// Block 1: Make proposal. Will have only 1 vote. No change.
+			with_env(|e| e.block_number = 1);
+			public::approve(&two, 1);
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 1);
+		});
+	}
+
+	#[test]
+	#[should_panic]
+	fn non_validator_approving_should_be_illegal() {
+		let one = one();
+		let two = two();
+		let three = [3u8; 32];
+		let four = [4u8; 32];
+		let mut t = new_test_ext();
+
+		with_externalities(&mut t, || {
+			assert_eq!(staking::era_length(), 1u64);
+			assert_eq!(staking::current_era(), 1u64);
+			assert_eq!(session::validator_count(), 3usize);
+			assert_eq!(session::validators(), vec![one.clone(), two.clone(), three.clone()]);
+			assert!(!session::validators().into_iter().position(|v| &v == &one).is_none());
+
+			// Block 1: Make proposal. Will have only 1 vote. No change.
+			with_env(|e| e.block_number = 1);
+			public::propose(&one, &Proposal {
+				function: InternalFunction::StakingSetSessionsPerEra,
+				input_data: vec![].join(&2u64),
+			});
+			public::approve(&four, 1);
+			staking::internal::check_new_era();
+			assert_eq!(staking::era_length(), 1);
+		});
+	}
+}
diff --git a/substrate/wasm-runtime/polkadot/src/runtime/mod.rs b/substrate/wasm-runtime/polkadot/src/runtime/mod.rs
index f83922c42f..9befa9bd42 100644
--- a/substrate/wasm-runtime/polkadot/src/runtime/mod.rs
+++ b/substrate/wasm-runtime/polkadot/src/runtime/mod.rs
@@ -26,5 +26,8 @@ pub mod staking;
 pub mod timestamp;
 #[allow(unused)]
 pub mod session;
+#[allow(unused)]
+pub mod governance;
 
-// TODO: governance, polkadao
+// TODO: polkadao
+// TODO: parachains
diff --git a/substrate/wasm-runtime/polkadot/src/runtime/session.rs b/substrate/wasm-runtime/polkadot/src/runtime/session.rs
index 6914bdc655..0402816fdc 100644
--- a/substrate/wasm-runtime/polkadot/src/runtime/session.rs
+++ b/substrate/wasm-runtime/polkadot/src/runtime/session.rs
@@ -17,119 +17,134 @@
 //! Session manager: is told the validators and allows them to manage their session keys for the
 //! consensus module.
 
-use runtime_support::prelude::*;
-use keyedvec::KeyedVec;
-use storable::{kill, Storable, StorageVec};
+use runtime_std::prelude::*;
+use codec::KeyedVec;
+use support::{storage, StorageVec};
 use primitives::{AccountID, SessionKey, BlockNumber};
 use runtime::{system, staking, consensus};
 
+const SESSION_LENGTH: &[u8] = b"ses:len";
+const CURRENT_INDEX: &[u8] = b"ses:ind";
+const LAST_LENGTH_CHANGE: &[u8] = b"ses:llc";
+const NEXT_KEY_FOR: &[u8] = b"ses:nxt:";
+const NEXT_SESSION_LENGTH: &[u8] = b"ses:nln";
+
 struct ValidatorStorageVec {}
 impl StorageVec for ValidatorStorageVec {
 	type Item = AccountID;
 	const PREFIX: &'static[u8] = b"ses:val:";
 }
 
-// TRANSACTION API (available to all transactors)
-
-/// Sets the session key of `_validator` to `_key`. This doesn't take effect until the next
-/// session.
-pub fn set_key(validator: &AccountID, key: &SessionKey) {
-	// set new value for next session
-	key.store(&validator.to_keyed_vec(b"ses:nxt:"));
-}
-
-// PUBLIC API (available to other runtime modules)
-
 /// Get the current set of authorities. These are the session keys.
 pub fn validators() -> Vec<AccountID> {
 	ValidatorStorageVec::items()
 }
 
-/// Set the current set of validators.
-///
-/// Called by staking::next_era() only. `next_session` should be called after this in order to
-/// update the session keys to the next validator set.
-pub fn set_validators(new: &[AccountID]) {
-	ValidatorStorageVec::set_items(new);
-	consensus::set_authorities(new);
-}
-
 /// The number of blocks in each session.
 pub fn length() -> BlockNumber {
-	Storable::lookup_default(b"ses:len")
+	storage::get_or(SESSION_LENGTH, 0)
+}
+
+/// The number of validators currently.
+pub fn validator_count() -> usize {
+	ValidatorStorageVec::count() as usize
 }
 
 /// The current era index.
 pub fn current_index() -> BlockNumber {
-	Storable::lookup_default(b"ses:ind")
-}
-
-/// Set the current era index.
-pub fn set_current_index(new: BlockNumber) {
-	new.store(b"ses:ind");
+	storage::get_or(CURRENT_INDEX, 0)
 }
 
 /// The block number at which the era length last changed.
 pub fn last_length_change() -> BlockNumber {
-	Storable::lookup_default(b"ses:llc")
+	storage::get_or(LAST_LENGTH_CHANGE, 0)
 }
 
-/// Set a new era length. Won't kick in until the next era change (at current length).
-pub fn set_length(new: BlockNumber) {
-	new.store(b"ses:nln");
-}
+pub mod public {
+	use super::*;
 
-/// Hook to be called after transaction processing.
-pub fn check_rotate_session() {
-	// do this last, after the staking system has had chance to switch out the authorities for the
-	// new set.
-	// check block number and call next_session if necessary.
-	if (system::block_number() - last_length_change()) % length() == 0 {
-		rotate_session();
+	/// Sets the session key of `_validator` to `_key`. This doesn't take effect until the next
+	/// session.
+	pub fn set_key(validator: &AccountID, key: &SessionKey) {
+		// set new value for next session
+		storage::put(&validator.to_keyed_vec(NEXT_KEY_FOR), key);
 	}
 }
 
-// PRIVATE (not available for use externally)
+pub mod privileged {
+	use super::*;
+
+	/// Set a new era length. Won't kick in until the next era change (at current length).
+	pub fn set_length(new: BlockNumber) {
+		storage::put(NEXT_SESSION_LENGTH, &new);
+	}
+}
+
+// INTERNAL API (available to other runtime modules)
+
+pub mod internal {
+	use super::*;
+
+	/// Set the current set of validators.
+	///
+	/// Called by staking::next_era() only. `next_session` should be called after this in order to
+	/// update the session keys to the next validator set.
+	pub fn set_validators(new: &[AccountID]) {
+		ValidatorStorageVec::set_items(new);
+		consensus::internal::set_authorities(new);
+	}
+
+	/// Hook to be called after transaction processing.
+	pub fn check_rotate_session() {
+		// do this last, after the staking system has had chance to switch out the authorities for the
+		// new set.
+		// check block number and call next_session if necessary.
+		if (system::block_number() - last_length_change()) % length() == 0 {
+			rotate_session();
+		}
+	}
+}
 
 /// Move onto next session: register the new authority set.
 fn rotate_session() {
 	// Increment current session index.
-	set_current_index(current_index() + 1);
+	storage::put(CURRENT_INDEX, &(current_index() + 1));
 
 	// Enact era length change.
-	if let Some(next_len) = u64::lookup(b"ses:nln") {
-		next_len.store(b"ses:len");
-		system::block_number().store(b"ses:llc");
-		kill(b"ses:nln");
+	if let Some(next_len) = storage::get::<u64>(NEXT_SESSION_LENGTH) {
+		storage::put(SESSION_LENGTH, &next_len);
+		storage::put(LAST_LENGTH_CHANGE, &system::block_number());
+		storage::kill(NEXT_SESSION_LENGTH);
 	}
 
 	// Update any changes in session keys.
 	validators().iter().enumerate().for_each(|(i, v)| {
-		let k = v.to_keyed_vec(b"ses:nxt:");
-		if let Some(n) = Storable::lookup(&k) {
-			consensus::set_authority(i as u32, &n);
-			kill(&k);
+		let k = v.to_keyed_vec(NEXT_KEY_FOR);
+		if let Some(n) = storage::take(&k) {
+			consensus::internal::set_authority(i as u32, &n);
 		}
 	});
 }
 
 #[cfg(test)]
 mod tests {
-	use runtime_support::{with_externalities, twox_128};
-	use keyedvec::KeyedVec;
-	use joiner::Joiner;
-	use testing::{one, two, TestExternalities};
+	use super::*;
+	use super::public::*;
+	use super::privileged::*;
+	use super::internal::*;
+	use runtime_std::{with_externalities, twox_128};
+	use codec::{KeyedVec, Joiner};
+	use support::{one, two, TestExternalities, with_env};
 	use primitives::AccountID;
 	use runtime::{consensus, session};
-	use environment::with_env;
 
 	fn simple_setup() -> TestExternalities {
 		TestExternalities { storage: map![
-			twox_128(b"ses:len").to_vec() => vec![].join(&2u64),
+			twox_128(SESSION_LENGTH).to_vec() => vec![].join(&2u64),
 			// the validators (10, 20, ...)
 			twox_128(b"ses:val:len").to_vec() => vec![].join(&2u32),
-			twox_128(&0u32.to_keyed_vec(b"ses:val:")).to_vec() => vec![10; 32],
-			twox_128(&1u32.to_keyed_vec(b"ses:val:")).to_vec() => vec![20; 32],
+			twox_128(&0u32.to_keyed_vec(ValidatorStorageVec::PREFIX)).to_vec() => vec![10; 32],
+			twox_128(&1u32.to_keyed_vec(ValidatorStorageVec::PREFIX)).to_vec() => vec![20; 32],
 			// initial session keys (11, 21, ...)
 			twox_128(b"con:aut:len").to_vec() => vec![].join(&2u32),
 			twox_128(&0u32.to_keyed_vec(b"con:aut:")).to_vec() => vec![11; 32],
@@ -142,8 +157,8 @@ mod tests {
 		let mut t = simple_setup();
 		with_externalities(&mut t, || {
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
-			assert_eq!(session::length(), 2u64);
-			assert_eq!(session::validators(), vec![[10u8; 32], [20u8; 32]]);
+			assert_eq!(length(), 2u64);
+			assert_eq!(validators(), vec![[10u8; 32], [20u8; 32]]);
 		});
 	}
 
@@ -153,48 +168,48 @@ mod tests {
 		with_externalities(&mut t, || {
 			// Block 1: Change to length 3; no visible change.
 			with_env(|e| e.block_number = 1);
-			session::set_length(3);
-			session::check_rotate_session();
-			assert_eq!(session::length(), 2);
-			assert_eq!(session::current_index(), 0);
+			set_length(3);
+			check_rotate_session();
+			assert_eq!(length(), 2);
+			assert_eq!(current_index(), 0);
 
 			// Block 2: Length now changed to 3. Index incremented.
 			with_env(|e| e.block_number = 2);
-			session::set_length(3);
-			session::check_rotate_session();
-			assert_eq!(session::length(), 3);
-			assert_eq!(session::current_index(), 1);
+			set_length(3);
+			check_rotate_session();
+			assert_eq!(length(), 3);
+			assert_eq!(current_index(), 1);
 
 			// Block 3: Length now changed to 3. Index incremented.
 			with_env(|e| e.block_number = 3);
-			session::check_rotate_session();
-			assert_eq!(session::length(), 3);
-			assert_eq!(session::current_index(), 1);
+			check_rotate_session();
+			assert_eq!(length(), 3);
+			assert_eq!(current_index(), 1);
 
 			// Block 4: Change to length 2; no visible change.
 			with_env(|e| e.block_number = 4);
-			session::set_length(2);
-			session::check_rotate_session();
-			assert_eq!(session::length(), 3);
-			assert_eq!(session::current_index(), 1);
+			set_length(2);
+			check_rotate_session();
+			assert_eq!(length(), 3);
+			assert_eq!(current_index(), 1);
 
 			// Block 5: Length now changed to 2. Index incremented.
 			with_env(|e| e.block_number = 5);
-			session::check_rotate_session();
-			assert_eq!(session::length(), 2);
-			assert_eq!(session::current_index(), 2);
+			check_rotate_session();
+			assert_eq!(length(), 2);
+			assert_eq!(current_index(), 2);
 
 			// Block 6: No change.
 			with_env(|e| e.block_number = 6);
-			session::check_rotate_session();
-			assert_eq!(session::length(), 2);
-			assert_eq!(session::current_index(), 2);
+			check_rotate_session();
+			assert_eq!(length(), 2);
+			assert_eq!(current_index(), 2);
 
 			// Block 7: Next index.
 			with_env(|e| e.block_number = 7);
-			session::check_rotate_session();
-			assert_eq!(session::length(), 2);
-			assert_eq!(session::current_index(), 3);
+			check_rotate_session();
+			assert_eq!(length(), 2);
+			assert_eq!(current_index(), 3);
 		});
 	}
 
@@ -204,25 +219,25 @@ mod tests {
 		with_externalities(&mut t, || {
 			// Block 1: No change
 			with_env(|e| e.block_number = 1);
-			session::check_rotate_session();
+			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 2: Session rollover, but no change.
 			with_env(|e| e.block_number = 2);
-			session::check_rotate_session();
+			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 3: Set new key for validator 2; no visible change.
 			with_env(|e| e.block_number = 3);
-			session::set_key(&[20; 32], &[22; 32]);
+			set_key(&[20; 32], &[22; 32]);
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
-			session::check_rotate_session();
+			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [21u8; 32]]);
 
 			// Block 4: Session rollover, authority 2 changes.
 			with_env(|e| e.block_number = 4);
-			session::check_rotate_session();
+			check_rotate_session();
 			assert_eq!(consensus::authorities(), vec![[11u8; 32], [22u8; 32]]);
 		});
 	}
diff --git a/substrate/wasm-runtime/polkadot/src/runtime/staking.rs b/substrate/wasm-runtime/polkadot/src/runtime/staking.rs
index 9b0c659f5c..d9bb971647 100644
--- a/substrate/wasm-runtime/polkadot/src/runtime/staking.rs
+++ b/substrate/wasm-runtime/polkadot/src/runtime/staking.rs
@@ -16,11 +16,12 @@
 
 //! Staking manager: Handles balances and periodically determines the best set of validators.
 
-use runtime_support::prelude::*;
-use keyedvec::KeyedVec;
-use storable::{Storable, StorageVec};
+use runtime_std::prelude::*;
+use runtime_std::cell::RefCell;
+use codec::KeyedVec;
+use support::{storage, StorageVec};
 use primitives::{BlockNumber, AccountID};
-use runtime::{system, session};
+use runtime::{system, session, governance};
 
 /// The balance of an account.
 pub type Balance = u64;
@@ -31,23 +32,26 @@ pub type Bondage = u64;
 struct IntentionStorageVec {}
 impl StorageVec for IntentionStorageVec {
 	type Item = AccountID;
-	const PREFIX: &'static[u8] = b"ses:wil:";
+	const PREFIX: &'static[u8] = b"sta:wil:";
 }
 
-// Each identity's stake may be in one of three bondage states, given by an integer:
-// - n | n <= current_era(): inactive: free to be transferred.
-// - ~0: active: currently representing a validator.
-// - n | n > current_era(): deactivating: recently representing a validator and not yet
-//   ready for transfer.
+const BONDING_DURATION: &[u8] = b"sta:loc";
+const VALIDATOR_COUNT: &[u8] = b"sta:vac";
+const SESSIONS_PER_ERA: &[u8] = b"sta:spe";
+const NEXT_SESSIONS_PER_ERA: &[u8] = b"sta:nse";
+const CURRENT_ERA: &[u8] = b"sta:era";
+const LAST_ERA_LENGTH_CHANGE: &[u8] = b"sta:lec";
+const BALANCE_OF: &[u8] = b"sta:bal:";
+const BONDAGE_OF: &[u8] = b"sta:bon:";
 
 /// The length of the bonding duration in eras.
 pub fn bonding_duration() -> BlockNumber {
-	Storable::lookup_default(b"sta:loc")
+	storage::get_or_default(BONDING_DURATION)
 }
 
 /// The length of a staking era in sessions.
 pub fn validator_count() -> usize {
-	u32::lookup_default(b"sta:vac") as usize
+	storage::get_or_default::<u32>(VALIDATOR_COUNT) as usize
 }
 
 /// The length of a staking era in blocks.
@@ -57,95 +61,129 @@ pub fn era_length() -> BlockNumber {
 
 /// The length of a staking era in sessions.
 pub fn sessions_per_era() -> BlockNumber {
-	Storable::lookup_default(b"sta:spe")
+	storage::get_or_default(SESSIONS_PER_ERA)
 }
 
 /// The current era index.
 pub fn current_era() -> BlockNumber {
-	Storable::lookup_default(b"sta:era")
+	storage::get_or_default(CURRENT_ERA)
 }
 
 /// The block number at which the era length last changed.
 pub fn last_era_length_change() -> BlockNumber {
-	Storable::lookup_default(b"sta:lec")
+	storage::get_or_default(LAST_ERA_LENGTH_CHANGE)
 }
 
 /// The balance of a given account.
 pub fn balance(who: &AccountID) -> Balance {
-	Storable::lookup_default(&who.to_keyed_vec(b"sta:bal:"))
+	storage::get_or_default(&who.to_keyed_vec(BALANCE_OF))
 }
 
 /// The liquidity-state of a given account.
 pub fn bondage(who: &AccountID) -> Bondage {
-	Storable::lookup_default(&who.to_keyed_vec(b"sta:bon:"))
+	storage::get_or_default(&who.to_keyed_vec(BONDAGE_OF))
 }
 
-/// Transfer some unlocked staking balance to another staker.
-pub fn transfer(transactor: &AccountID, dest: &AccountID, value: Balance) {
-	let from_key = transactor.to_keyed_vec(b"sta:bal:");
-	let from_balance = Balance::lookup_default(&from_key);
-	assert!(from_balance >= value);
-	let to_key = dest.to_keyed_vec(b"sta:bal:");
-	let to_balance: Balance = Storable::lookup_default(&to_key);
-	assert!(bondage(transactor) <= bondage(dest));
-	assert!(to_balance + value > to_balance);	// no overflow
-	(from_balance - value).store(&from_key);
-	(to_balance + value).store(&to_key);
-}
+// Each identity's stake may be in one of three bondage states, given by an integer:
+// - n | n <= current_era(): inactive: free to be transferred.
+// - ~0: active: currently representing a validator.
+// - n | n > current_era(): deactivating: recently representing a validator and not yet
+//   ready for transfer.
 
-/// Declare the desire to stake for the transactor.
-///
-/// Effects will be felt at the beginning of the next era.
-pub fn stake(transactor: &AccountID) {
-	let mut intentions = IntentionStorageVec::items();
-	// can't be in the list twice.
-	assert!(intentions.iter().find(|t| *t == transactor).is_none(), "Cannot stake if already staked.");
-	intentions.push(transactor.clone());
-	IntentionStorageVec::set_items(&intentions);
-	u64::max_value().store(&transactor.to_keyed_vec(b"sta:bon:"));
-}
+pub mod public {
+	use super::*;
 
-/// Retract the desire to stake for the transactor.
-///
-/// Effects will be felt at the beginning of the next era.
-pub fn unstake(transactor: &AccountID) {
-	let mut intentions = IntentionStorageVec::items();
-	if let Some(position) = intentions.iter().position(|t| t == transactor) {
-		intentions.swap_remove(position);
-	} else {
-		panic!("Cannot unstake if not already staked.");
+	/// Transfer some unlocked staking balance to another staker.
+	pub fn transfer(transactor: &AccountID, dest: &AccountID, value: Balance) {
+		let from_key = transactor.to_keyed_vec(BALANCE_OF);
+		let from_balance = storage::get_or_default::<Balance>(&from_key);
+		assert!(from_balance >= value);
+		let to_key = dest.to_keyed_vec(BALANCE_OF);
+		let to_balance: Balance = storage::get_or_default(&to_key);
+		assert!(bondage(transactor) <= bondage(dest));
+		assert!(to_balance + value > to_balance);	// no overflow
+		storage::put(&from_key, &(from_balance - value));
+		storage::put(&to_key, &(to_balance + value));
 	}
-	IntentionStorageVec::set_items(&intentions);
-	(current_era() + bonding_duration()).store(&transactor.to_keyed_vec(b"sta:bon:"));
-}
 
-/// Hook to be called after to transaction processing.
-pub fn check_new_era() {
-	// check block number and call new_era if necessary.
-	if (system::block_number() - last_era_length_change()) % era_length() == 0 {
-		new_era();
+	/// Declare the desire to stake for the transactor.
+	///
+	/// Effects will be felt at the beginning of the next era.
+	pub fn stake(transactor: &AccountID) {
+		let mut intentions = IntentionStorageVec::items();
+		// can't be in the list twice.
+		assert!(intentions.iter().find(|t| *t == transactor).is_none(), "Cannot stake if already staked.");
+		intentions.push(transactor.clone());
+		IntentionStorageVec::set_items(&intentions);
+		storage::put(&transactor.to_keyed_vec(BONDAGE_OF), &u64::max_value());
+	}
+
+	/// Retract the desire to stake for the transactor.
+	///
+	/// Effects will be felt at the beginning of the next era.
+	pub fn unstake(transactor: &AccountID) {
+		let mut intentions = IntentionStorageVec::items();
+		if let Some(position) = intentions.iter().position(|t| t == transactor) {
+			intentions.swap_remove(position);
+		} else {
+			panic!("Cannot unstake if not already staked.");
+		}
+		IntentionStorageVec::set_items(&intentions);
+		storage::put(&transactor.to_keyed_vec(BONDAGE_OF), &(current_era() + bonding_duration()));
 	}
 }
 
-// PRIVATE
+pub mod privileged {
+	use super::*;
+
+	/// Set the number of sessions in an era.
+	pub fn set_sessions_per_era(new: BlockNumber) {
+		storage::put(NEXT_SESSIONS_PER_ERA, &new);
+	}
+
+	/// The length of the bonding duration in eras.
+	pub fn set_bonding_duration(new: BlockNumber) {
+		storage::put(BONDING_DURATION, &new);
+	}
+
+	/// The length of a staking era in sessions.
+	pub fn set_validator_count(new: usize) {
+		storage::put(VALIDATOR_COUNT, &(new as u32));
+	}
+}
+
+pub mod internal {
+	use super::*;
+
+	/// Hook to be called after to transaction processing.
+	pub fn check_new_era() {
+		// check block number and call new_era if necessary.
+		if (system::block_number() - last_era_length_change()) % era_length() == 0 {
+			new_era();
+		}
+	}
+}
 
 /// The era has changed - enact new staking set.
 ///
-/// NOTE: This always happens on a session change.
+/// NOTE: This always happens immediately before a session change to ensure that new validators
+/// get a chance to set their session keys.
 fn new_era() {
+	// Inform governance module that it's the end of an era
+	governance::internal::end_of_an_era();
+
 	// Increment current era.
-	(current_era() + 1).store(b"sta:era");
+	storage::put(CURRENT_ERA, &(current_era() + 1));
 
 	// Enact era length change.
-	let next_spe: u64 = Storable::lookup_default(b"sta:nse");
+	let next_spe: u64 = storage::get_or_default(NEXT_SESSIONS_PER_ERA);
 	if next_spe > 0 && next_spe != sessions_per_era() {
-		next_spe.store(b"sta:spe");
-		system::block_number().store(b"sta:lec");
+		storage::put(SESSIONS_PER_ERA, &next_spe);
+		storage::put(LAST_ERA_LENGTH_CHANGE, &system::block_number());
 	}
 
-	// TODO: evaluate desired staking amounts and nominations and optimise to find the best
-	// combination of validators, then use session::set_validators().
-
+	// evaluate desired staking amounts and nominations and optimise to find the best
+	// combination of validators, then use session::internal::set_validators().
 	// for now, this just orders would-be stakers by their balances and chooses the top-most
 	// validator_count() of them.
 	let mut intentions = IntentionStorageVec::items()
@@ -153,7 +191,7 @@ fn new_era() {
 		.map(|v| (balance(&v), v))
 		.collect::<Vec<_>>();
 	intentions.sort_unstable_by(|&(b1, _), &(b2, _)| b2.cmp(&b1));
-	session::set_validators(
+	session::internal::set_validators(
 		&intentions.into_iter()
 			.map(|(_, v)| v)
 			.take(validator_count())
@@ -161,20 +199,18 @@ fn new_era() {
 	);
 }
 
-/// Set a new era length. Won't kick in until the next era change (at current length).
-fn set_sessions_per_era(new: BlockNumber) {
-	new.store(b"sta:nse");
-}
-
 #[cfg(test)]
 mod tests {
-	use runtime_support::{with_externalities, twox_128};
-	use keyedvec::KeyedVec;
-	use joiner::Joiner;
-	use testing::{one, two, TestExternalities};
+	use super::*;
+	use super::internal::*;
+	use super::public::*;
+	use super::privileged::*;
+
+	use runtime_std::{with_externalities, twox_128};
+	use codec::{KeyedVec, Joiner};
+	use support::{one, two, TestExternalities, with_env};
 	use primitives::AccountID;
 	use runtime::{staking, session};
-	use environment::with_env;
 
 	#[test]
 	fn staking_should_work() {
@@ -188,64 +224,64 @@ mod tests {
 			twox_128(b"ses:val:len").to_vec() => vec![].join(&2u32),
 			twox_128(&0u32.to_keyed_vec(b"ses:val:")).to_vec() => vec![10; 32],
 			twox_128(&1u32.to_keyed_vec(b"ses:val:")).to_vec() => vec![20; 32],
-			twox_128(b"sta:spe").to_vec() => vec![].join(&2u64),
-			twox_128(b"sta:vac").to_vec() => vec![].join(&2u32),
-			twox_128(b"sta:loc").to_vec() => vec![].join(&3u64),
-			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![].join(&10u64),
-			twox_128(&two.to_keyed_vec(b"sta:bal:")).to_vec() => vec![].join(&20u64),
-			twox_128(&three.to_keyed_vec(b"sta:bal:")).to_vec() => vec![].join(&30u64),
-			twox_128(&four.to_keyed_vec(b"sta:bal:")).to_vec() => vec![].join(&40u64)
+			twox_128(SESSIONS_PER_ERA).to_vec() => vec![].join(&2u64),
+			twox_128(VALIDATOR_COUNT).to_vec() => vec![].join(&2u32),
+			twox_128(BONDING_DURATION).to_vec() => vec![].join(&3u64),
+			twox_128(&one.to_keyed_vec(BALANCE_OF)).to_vec() => vec![].join(&10u64),
+			twox_128(&two.to_keyed_vec(BALANCE_OF)).to_vec() => vec![].join(&20u64),
+			twox_128(&three.to_keyed_vec(BALANCE_OF)).to_vec() => vec![].join(&30u64),
+			twox_128(&four.to_keyed_vec(BALANCE_OF)).to_vec() => vec![].join(&40u64)
 		], };
 
 		with_externalities(&mut t, || {
-			assert_eq!(staking::era_length(), 2u64);
-			assert_eq!(staking::validator_count(), 2usize);
-			assert_eq!(staking::bonding_duration(), 3u64);
+			assert_eq!(era_length(), 2u64);
+			assert_eq!(validator_count(), 2usize);
+			assert_eq!(bonding_duration(), 3u64);
 			assert_eq!(session::validators(), vec![[10u8; 32], [20u8; 32]]);
 
 			// Block 1: Add three validators. No obvious change.
 			with_env(|e| e.block_number = 1);
-			staking::stake(&one);
-			staking::stake(&two);
-			staking::stake(&four);
-			staking::check_new_era();
+			stake(&one);
+			stake(&two);
+			stake(&four);
+			check_new_era();
 			assert_eq!(session::validators(), vec![[10u8; 32], [20u8; 32]]);
 
 			// Block 2: New validator set now.
 			with_env(|e| e.block_number = 2);
-			staking::check_new_era();
+			check_new_era();
 			assert_eq!(session::validators(), vec![four.clone(), two.clone()]);
 
 			// Block 3: Unstake highest, introduce another staker. No change yet.
 			with_env(|e| e.block_number = 3);
-			staking::stake(&three);
-			staking::unstake(&four);
-			staking::check_new_era();
+			stake(&three);
+			unstake(&four);
+			check_new_era();
 
 			// Block 4: New era - validators change.
 			with_env(|e| e.block_number = 4);
-			staking::check_new_era();
+			check_new_era();
 			assert_eq!(session::validators(), vec![three.clone(), two.clone()]);
 
 			// Block 5: Transfer stake from highest to lowest. No change yet.
 			with_env(|e| e.block_number = 5);
-			staking::transfer(&four, &one, 40);
-			staking::check_new_era();
+			transfer(&four, &one, 40);
+			check_new_era();
 
 			// Block 6: Lowest now validator.
 			with_env(|e| e.block_number = 6);
-			staking::check_new_era();
+			check_new_era();
 			assert_eq!(session::validators(), vec![one.clone(), three.clone()]);
 
 			// Block 7: Unstake three. No change yet.
 			with_env(|e| e.block_number = 7);
-			staking::unstake(&three);
-			staking::check_new_era();
+			unstake(&three);
+			check_new_era();
 			assert_eq!(session::validators(), vec![one.clone(), three.clone()]);
 
 			// Block 8: Back to one and two.
 			with_env(|e| e.block_number = 8);
-			staking::check_new_era();
+			check_new_era();
 			assert_eq!(session::validators(), vec![one.clone(), two.clone()]);
 		});
 	}
@@ -254,63 +290,63 @@ mod tests {
 	fn staking_eras_work() {
 		let mut t = TestExternalities { storage: map![
 			twox_128(b"ses:len").to_vec() => vec![].join(&1u64),
-			twox_128(b"sta:spe").to_vec() => vec![].join(&2u64)
+			twox_128(SESSIONS_PER_ERA).to_vec() => vec![].join(&2u64)
 		], };
 		with_externalities(&mut t, || {
-			assert_eq!(staking::era_length(), 2u64);
-			assert_eq!(staking::sessions_per_era(), 2u64);
-			assert_eq!(staking::last_era_length_change(), 0u64);
-			assert_eq!(staking::current_era(), 0u64);
+			assert_eq!(era_length(), 2u64);
+			assert_eq!(sessions_per_era(), 2u64);
+			assert_eq!(last_era_length_change(), 0u64);
+			assert_eq!(current_era(), 0u64);
 
 			// Block 1: No change.
 			with_env(|e| e.block_number = 1);
-			staking::check_new_era();
-			assert_eq!(staking::sessions_per_era(), 2u64);
-			assert_eq!(staking::last_era_length_change(), 0u64);
-			assert_eq!(staking::current_era(), 0u64);
+			check_new_era();
+			assert_eq!(sessions_per_era(), 2u64);
+			assert_eq!(last_era_length_change(), 0u64);
+			assert_eq!(current_era(), 0u64);
 
 			// Block 2: Simple era change.
 			with_env(|e| e.block_number = 2);
-			staking::check_new_era();
-			assert_eq!(staking::sessions_per_era(), 2u64);
-			assert_eq!(staking::last_era_length_change(), 0u64);
-			assert_eq!(staking::current_era(), 1u64);
+			check_new_era();
+			assert_eq!(sessions_per_era(), 2u64);
+			assert_eq!(last_era_length_change(), 0u64);
+			assert_eq!(current_era(), 1u64);
 
 			// Block 3: Schedule an era length change; no visible changes.
 			with_env(|e| e.block_number = 3);
-			staking::set_sessions_per_era(3);
-			staking::check_new_era();
-			assert_eq!(staking::sessions_per_era(), 2u64);
-			assert_eq!(staking::last_era_length_change(), 0u64);
-			assert_eq!(staking::current_era(), 1u64);
+			set_sessions_per_era(3);
+			check_new_era();
+			assert_eq!(sessions_per_era(), 2u64);
+			assert_eq!(last_era_length_change(), 0u64);
+			assert_eq!(current_era(), 1u64);
 
 			// Block 4: Era change kicks in.
 			with_env(|e| e.block_number = 4);
-			staking::check_new_era();
-			assert_eq!(staking::sessions_per_era(), 3u64);
-			assert_eq!(staking::last_era_length_change(), 4u64);
-			assert_eq!(staking::current_era(), 2u64);
+			check_new_era();
+			assert_eq!(sessions_per_era(), 3u64);
+			assert_eq!(last_era_length_change(), 4u64);
+			assert_eq!(current_era(), 2u64);
 
 			// Block 5: No change.
 			with_env(|e| e.block_number = 5);
-			staking::check_new_era();
-			assert_eq!(staking::sessions_per_era(), 3u64);
-			assert_eq!(staking::last_era_length_change(), 4u64);
-			assert_eq!(staking::current_era(), 2u64);
+			check_new_era();
+			assert_eq!(sessions_per_era(), 3u64);
+			assert_eq!(last_era_length_change(), 4u64);
+			assert_eq!(current_era(), 2u64);
 
 			// Block 6: No change.
 			with_env(|e| e.block_number = 6);
-			staking::check_new_era();
-			assert_eq!(staking::sessions_per_era(), 3u64);
-			assert_eq!(staking::last_era_length_change(), 4u64);
-			assert_eq!(staking::current_era(), 2u64);
+			check_new_era();
+			assert_eq!(sessions_per_era(), 3u64);
+			assert_eq!(last_era_length_change(), 4u64);
+			assert_eq!(current_era(), 2u64);
 
 			// Block 7: Era increment.
 			with_env(|e| e.block_number = 7);
-			staking::check_new_era();
-			assert_eq!(staking::sessions_per_era(), 3u64);
-			assert_eq!(staking::last_era_length_change(), 4u64);
-			assert_eq!(staking::current_era(), 3u64);
+			check_new_era();
+			assert_eq!(sessions_per_era(), 3u64);
+			assert_eq!(last_era_length_change(), 4u64);
+			assert_eq!(current_era(), 3u64);
 		});
 	}
 
@@ -320,12 +356,12 @@ mod tests {
 		let two = two();
 
 		let mut t = TestExternalities { storage: map![
-			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![].join(&42u64)
+			twox_128(&one.to_keyed_vec(BALANCE_OF)).to_vec() => vec![].join(&42u64)
 		], };
 
 		with_externalities(&mut t, || {
-			assert_eq!(staking::balance(&one), 42);
-			assert_eq!(staking::balance(&two), 0);
+			assert_eq!(balance(&one), 42);
+			assert_eq!(balance(&two), 0);
 		});
 	}
 
@@ -335,13 +371,13 @@ mod tests {
 		let two = two();
 
 		let mut t = TestExternalities { storage: map![
-			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![].join(&111u64)
+			twox_128(&one.to_keyed_vec(BALANCE_OF)).to_vec() => vec![].join(&111u64)
 		], };
 
 		with_externalities(&mut t, || {
-			staking::transfer(&one, &two, 69);
-			assert_eq!(staking::balance(&one), 42);
-			assert_eq!(staking::balance(&two), 69);
+			transfer(&one, &two, 69);
+			assert_eq!(balance(&one), 42);
+			assert_eq!(balance(&two), 69);
 		});
 	}
 
@@ -352,12 +388,12 @@ mod tests {
 		let two = two();
 
 		let mut t = TestExternalities { storage: map![
-			twox_128(&one.to_keyed_vec(b"sta:bal:")).to_vec() => vec![].join(&111u64)
+			twox_128(&one.to_keyed_vec(BALANCE_OF)).to_vec() => vec![].join(&111u64)
 		], };
 
 		with_externalities(&mut t, || {
-			staking::stake(&one);
-			staking::transfer(&one, &two, 69);
+			stake(&one);
+			transfer(&one, &two, 69);
 		});
 	}
 }
diff --git a/substrate/wasm-runtime/polkadot/src/runtime/system.rs b/substrate/wasm-runtime/polkadot/src/runtime/system.rs
index 072e17df01..a6bf24718e 100644
--- a/substrate/wasm-runtime/polkadot/src/runtime/system.rs
+++ b/substrate/wasm-runtime/polkadot/src/runtime/system.rs
@@ -17,14 +17,16 @@
 //! System manager: Handles all of the top-level stuff; executing block/transaction, setting code
 //! and depositing logs.
 
-use primitives::{Block, BlockNumber, Hash, UncheckedTransaction, TxOrder, Hashable};
-use runtime_support::mem;
-use runtime_support::prelude::*;
-use storable::Storable;
-use keyedvec::KeyedVec;
-use environment::with_env;
+use runtime_std::prelude::*;
+use runtime_std::{mem, print};
+use codec::KeyedVec;
+use support::{Hashable, storage, with_env};
+use primitives::{Block, BlockNumber, Hash, UncheckedTransaction, TxOrder};
 use runtime::{staking, session};
 
+const BLOCK_HASH_AT: &[u8] = b"sys:old:";
+const CODE: &[u8] = b"sys:cod";
+
 /// The current block number being processed. Set by `execute_block`.
 pub fn block_number() -> BlockNumber {
 	with_env(|e| e.block_number)
@@ -32,77 +34,86 @@ pub fn block_number() -> BlockNumber {
 
 /// Get the block hash of a given block (uses storage).
 pub fn block_hash(number: BlockNumber) -> Hash {
-	Storable::lookup_default(&number.to_keyed_vec(b"sys:old:"))
+	storage::get_or_default(&number.to_keyed_vec(BLOCK_HASH_AT))
 }
 
-/// Deposits a log and ensures it matches the blocks log data.
-pub fn deposit_log(log: &[u8]) {
-	with_env(|e| {
-		assert_eq!(log, &e.digest.logs[e.next_log_index][..]);
-		e.next_log_index += 1;
-	});
+pub mod privileged {
+	use super::*;
+
+	/// Set the new code.
+	pub fn set_code(new: &[u8]) {
+		storage::put_raw(CODE, new);
+	}
 }
 
-pub fn execute_block(mut block: Block) {
-	// populate environment from header.
-	with_env(|e| {
-		e.block_number = block.header.number;
-		mem::swap(&mut e.digest, &mut block.header.digest);
-		e.next_log_index = 0;
-	});
+pub mod internal {
+	use super::*;
 
-	let ref header = block.header;
+	/// Deposits a log and ensures it matches the blocks log data.
+	pub fn deposit_log(log: &[u8]) {
+		with_env(|e| {
+			assert_eq!(log, &e.digest.logs[e.next_log_index][..]);
+			e.next_log_index += 1;
+		});
+	}
 
-	// check parent_hash is correct.
-	assert!(
-		header.number > 0 && block_hash(header.number - 1) == header.parent_hash,
-		"Parent hash should be valid."
-	);
+	/// Actually execute all transitioning for `block`.
+	pub fn execute_block(mut block: Block) {
+		// populate environment from header.
+		with_env(|e| {
+			e.block_number = block.header.number;
+			mem::swap(&mut e.digest, &mut block.header.digest);
+			e.next_log_index = 0;
+		});
 
-	// TODO: check transaction trie root represents the transactions.
-	// this requires non-trivial changes to the externals API or compiling trie rooting into wasm
-	// so will wait until a little later.
+		let ref header = block.header;
 
-	// store the header hash in storage.
-	let header_hash_key = header.number.to_keyed_vec(b"sys:old:");
-	header.blake2_256().store(&header_hash_key);
+		// check parent_hash is correct.
+		assert!(
+			header.number > 0 && block_hash(header.number - 1) == header.parent_hash,
+			"Parent hash should be valid."
+		);
 
-	// execute transactions
-	block.transactions.iter().for_each(execute_transaction);
+		// TODO: check transaction trie root represents the transactions.
+		// this requires non-trivial changes to the externals API or compiling trie rooting into wasm
+		// so will wait until a little later.
 
-	staking::check_new_era();
-	session::check_rotate_session();
+		// store the header hash in storage.
+		let header_hash_key = header.number.to_keyed_vec(BLOCK_HASH_AT);
+		storage::put(&header_hash_key, &header.blake2_256());
 
-	// any final checks
-	final_checks(&block);
+		// execute transactions
+		block.transactions.iter().for_each(execute_transaction);
 
-	// TODO: check storage root.
-	// this requires non-trivial changes to the externals API or compiling trie rooting into wasm
-	// so will wait until a little later.
-}
+		staking::internal::check_new_era();
+		session::internal::check_rotate_session();
 
-/// Execute a given transaction.
-pub fn execute_transaction(utx: &UncheckedTransaction) {
-	// Verify the signature is good.
-	assert!(utx.ed25519_verify(), "All transactions should be properly signed");
+		// any final checks
+		final_checks(&block);
 
-	let ref tx = utx.transaction;
+		// TODO: check storage root.
+		// this requires non-trivial changes to the externals API or compiling trie rooting into wasm
+		// so will wait until a little later.
+	}
 
-	// check nonce
-	let nonce_key = tx.signed.to_keyed_vec(b"sys:non:");
-	let expected_nonce: TxOrder = Storable::lookup_default(&nonce_key);
-	assert!(tx.nonce == expected_nonce, "All transactions should have the correct nonce");
+	/// Execute a given transaction.
+	pub fn execute_transaction(utx: &UncheckedTransaction) {
+		// Verify the signature is good.
+		assert!(utx.ed25519_verify(), "All transactions should be properly signed");
 
-	// increment nonce in storage
-	(expected_nonce + 1).store(&nonce_key);
+		let ref tx = utx.transaction;
 
-	// decode parameters and dispatch
-	tx.function.dispatch(&tx.signed, &tx.input_data);
-}
+		// check nonce
+		let nonce_key = tx.signed.to_keyed_vec(b"sys:non:");
+		let expected_nonce: TxOrder = storage::get_or_default(&nonce_key);
+		assert!(tx.nonce == expected_nonce, "All transactions should have the correct nonce");
 
-/// Set the new code.
-pub fn set_code(new: &[u8]) {
-	new.store(b":code");
+		// increment nonce in storage
+		storage::put(&nonce_key, &(expected_nonce + 1));
+
+		// decode parameters and dispatch
+		tx.function.dispatch(&tx.signed, &tx.input_data);
+	}
 }
 
 fn final_checks(_block: &Block) {
@@ -113,15 +124,14 @@ fn final_checks(_block: &Block) {
 
 #[cfg(test)]
 mod tests {
-	use joiner::Joiner;
-	use function::Function;
-	use keyedvec::KeyedVec;
-	use slicable::Slicable;
-	use runtime_support::{with_externalities, twox_128};
-	use primitives::{UncheckedTransaction, Transaction};
-	use statichex::StaticHexInto;
-	use runtime::{system, staking};
-	use testing::{TestExternalities, HexDisplay, one, two};
+	use super::*;
+	use super::internal::*;
+
+	use runtime_std::{with_externalities, twox_128};
+	use codec::{Joiner, KeyedVec, Slicable};
+	use support::{StaticHexInto, TestExternalities, HexDisplay, one, two};
+	use primitives::{UncheckedTransaction, Transaction, Function};
+	use runtime::staking;
 
 	#[test]
 	fn staking_balance_transfer_dispatch_works() {
@@ -147,7 +157,7 @@ mod tests {
 		println!("tx is {}", HexDisplay::from(&tx.transaction.to_vec()));
 
 		with_externalities(&mut t, || {
-			system::execute_transaction(&tx);
+			execute_transaction(&tx);
 			assert_eq!(staking::balance(&one), 42);
 			assert_eq!(staking::balance(&two), 69);
 		});
diff --git a/substrate/wasm-runtime/polkadot/src/runtime/timestamp.rs b/substrate/wasm-runtime/polkadot/src/runtime/timestamp.rs
index 7040473b1a..f0a798d112 100644
--- a/substrate/wasm-runtime/polkadot/src/runtime/timestamp.rs
+++ b/substrate/wasm-runtime/polkadot/src/runtime/timestamp.rs
@@ -16,39 +16,47 @@
 
 //! Timestamp manager: just handles the current timestamp.
 
-use storable::Storable;
+use support::storage;
+
+const CURRENT_TIMESTAMP: &[u8] = b"tim:val";
 
 /// Representation of a time.
 pub type Timestamp = u64;
 
 /// Get the current time.
 pub fn get() -> Timestamp {
-	Storable::lookup_default(b"tim:val")
+	storage::get_or_default(CURRENT_TIMESTAMP)
 }
 
-/// Set the current time.
-pub fn set(now: Timestamp) {
-	now.store(b"tim:val")
+pub mod public {
+	use super::*;
+
+	/// Set the current time.
+	pub fn set(now: Timestamp) {
+		storage::put(CURRENT_TIMESTAMP, &now);
+	}
 }
 
 #[cfg(test)]
 mod tests {
-	use joiner::Joiner;
-	use keyedvec::KeyedVec;
-	use runtime_support::{with_externalities, twox_128};
+	use super::*;
+	use super::public::*;
+
+	use runtime_std::{with_externalities, twox_128};
 	use runtime::timestamp;
-	use testing::TestExternalities;
+	use codec::{Joiner, KeyedVec};
+	use support::TestExternalities;
 
 	#[test]
 	fn timestamp_works() {
 		let mut t = TestExternalities { storage: map![
-			twox_128(b"tim:val").to_vec() => vec![].join(&42u64)
+			twox_128(CURRENT_TIMESTAMP).to_vec() => vec![].join(&42u64)
 		], };
 
 		with_externalities(&mut t, || {
-			assert_eq!(timestamp::get(), 42);
-			timestamp::set(69);
-			assert_eq!(timestamp::get(), 69);
+			assert_eq!(get(), 42);
+			set(69);
+			assert_eq!(get(), 69);
 		});
 	}
 }
diff --git a/substrate/wasm-runtime/polkadot/src/support/environment.rs b/substrate/wasm-runtime/polkadot/src/support/environment.rs
index 1011b3168b..7670a4801f 100644
--- a/substrate/wasm-runtime/polkadot/src/support/environment.rs
+++ b/substrate/wasm-runtime/polkadot/src/support/environment.rs
@@ -16,10 +16,10 @@
 
 //! Environment API: Allows certain information to be accessed throughout the runtime.
 
-use runtime_support::boxed::Box;
-use runtime_support::mem;
-use runtime_support::cell::RefCell;
-use runtime_support::rc::Rc;
+use runtime_std::boxed::Box;
+use runtime_std::mem;
+use runtime_std::cell::RefCell;
+use runtime_std::rc::Rc;
 
 use primitives::{BlockNumber, Digest};
 
diff --git a/substrate/wasm-runtime/polkadot/src/support/hashable.rs b/substrate/wasm-runtime/polkadot/src/support/hashable.rs
new file mode 100644
index 0000000000..66c3844fda
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/support/hashable.rs
@@ -0,0 +1,38 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Hashable trait.
+
+use codec::Slicable;
+use runtime_std::{blake2_256, twox_128, twox_256};
+
+pub trait Hashable: Sized {
+	fn blake2_256(&self) -> [u8; 32];
+	fn twox_128(&self) -> [u8; 16];
+	fn twox_256(&self) -> [u8; 32];
+}
+
+impl<T: Slicable> Hashable for T {
+	fn blake2_256(&self) -> [u8; 32] {
+		blake2_256(&self.to_vec())
+	}
+	fn twox_128(&self) -> [u8; 16] {
+		twox_128(&self.to_vec())
+	}
+	fn twox_256(&self) -> [u8; 32] {
+		twox_256(&self.to_vec())
+	}
+}
diff --git a/substrate/wasm-runtime/polkadot/src/support/mod.rs b/substrate/wasm-runtime/polkadot/src/support/mod.rs
index 56ad3a355c..6bc60880a0 100644
--- a/substrate/wasm-runtime/polkadot/src/support/mod.rs
+++ b/substrate/wasm-runtime/polkadot/src/support/mod.rs
@@ -16,13 +16,19 @@
 
 //! Support code for the runtime.
 
-pub mod primitives;
-pub mod function;
-pub mod environment;
-pub mod storable;
-
-#[cfg(test)]
-pub mod statichex;
-#[cfg(test)]
+mod environment;
+pub mod storage;
+mod hashable;
+#[cfg(feature = "with-std")]
+mod statichex;
 #[macro_use]
-pub mod testing;
+#[cfg(feature = "with-std")]
+mod testing;
+
+pub use self::environment::with_env;
+pub use self::storage::StorageVec;
+pub use self::hashable::Hashable;
+#[cfg(feature = "with-std")]
+pub use self::statichex::{StaticHexConversion, StaticHexInto};
+#[cfg(feature = "with-std")]
+pub use self::testing::{AsBytesRef, HexDisplay, TestExternalities, one, two};
diff --git a/substrate/wasm-runtime/polkadot/src/support/primitives.rs b/substrate/wasm-runtime/polkadot/src/support/primitives.rs
deleted file mode 100644
index 338be80710..0000000000
--- a/substrate/wasm-runtime/polkadot/src/support/primitives.rs
+++ /dev/null
@@ -1,515 +0,0 @@
-// Copyright 2017 Parity Technologies (UK) Ltd.
-// This file is part of Polkadot.
-
-// Polkadot 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.
-
-// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
-
-//! Primitive types.
-
-use runtime_support::prelude::*;
-use streamreader::StreamReader;
-use joiner::Joiner;
-use slicable::{Slicable, NonTrivialSlicable};
-use function::Function;
-use runtime_support::{mem, blake2_256, twox_128, twox_256, ed25519_verify};
-
-#[cfg(test)]
-use std::fmt;
-
-/// The Ed25519 pubkey that identifies an account.
-pub type AccountID = [u8; 32];
-/// The Ed25519 pub key of an session that belongs to an authority. This is used as what the
-/// external environment/consensus algorithm calls an "authority".
-pub type SessionKey = AccountID;
-/// Indentifier for a chain.
-pub type ChainID = u64;
-/// Index of a block in the chain.
-pub type BlockNumber = u64;
-/// Index of a transaction.
-pub type TxOrder = u64;
-/// A hash of some data.
-pub type Hash = [u8; 32];
-
-#[derive(Clone, Default)]
-#[cfg_attr(test, derive(PartialEq, Debug))]
-/// The digest of a block, useful for light-clients.
-pub struct Digest {
-	/// All logs that have happened in the block.
-	pub logs: Vec<Vec<u8>>,
-}
-
-#[derive(Clone)]
-#[cfg_attr(test, derive(PartialEq, Debug))]
-/// The header for a block.
-pub struct Header {
-	/// The parent block's "hash" (actually the Blake2-256 hash of its serialised header).
-	pub parent_hash: Hash,
-	/// The block's number (how many ancestors does it have?).
-	pub number: BlockNumber,
-	/// The root of the trie that represents this block's final storage map.
-	pub state_root: Hash,
-	/// The root of the trie that represents this block's transactions, indexed by a 32-bit integer.
-	pub transaction_root: Hash,
-	/// The digest for this block.
-	pub digest: Digest,
-}
-
-impl Slicable for Header {
-	fn from_slice(value: &[u8]) -> Option<Self> {
-		let mut reader = StreamReader::new(value);
-		Some(Header {
-			parent_hash: reader.read()?,
-			number: reader.read()?,
-			state_root: reader.read()?,
-			transaction_root: reader.read()?,
-			digest: Digest { logs: reader.read()?, },
-		})
-	}
-
-	fn set_as_slice<F: FnOnce(&mut [u8]) -> bool>(_fill_slice: F) -> Option<Self> {
-		unimplemented!();
-	}
-
-	fn to_vec(&self) -> Vec<u8> {
-		Vec::new()
-			.join(&self.parent_hash)
-			.join(&self.number)
-			.join(&self.state_root)
-			.join(&self.transaction_root)
-			.join(&self.digest.logs)
-	}
-
-	fn size_of(data: &[u8]) -> Option<usize> {
-		let first_part = mem::size_of::<Hash>() + mem::size_of::<BlockNumber>() + mem::size_of::<Hash>() + mem::size_of::<Hash>();
-		let second_part = <Vec<Vec<u8>>>::size_of(&data[first_part..])?;
-		Some(first_part + second_part)
-	}
-}
-
-impl NonTrivialSlicable for Header {}
-
-#[cfg_attr(test, derive(PartialEq, Debug))]
-/// A vetted and verified transaction from the external world.
-pub struct Transaction {
-	/// Who signed it (note this is not a signature).
-	pub signed: AccountID,
-	/// The number of transactions have come before from the same signer.
-	pub nonce: TxOrder,
-	/// The function that should be called.
-	pub function: Function,
-	/// Serialised input data to the function.
-	pub input_data: Vec<u8>,
-}
-
-impl Slicable for Transaction {
-	fn from_slice(value: &[u8]) -> Option<Self> {
-		let mut reader = StreamReader::new(value);
-		Some(Transaction {
-			signed: reader.read()?,
-			nonce: reader.read()?,
-			function: Function::from_u8(reader.read()?)?,
-			input_data: reader.read()?,
-		})
-	}
-
-	fn set_as_slice<F: FnOnce(&mut [u8]) -> bool>(_fill_slice: F) -> Option<Self> {
-		unimplemented!();
-	}
-
-	fn to_vec(&self) -> Vec<u8> {
-		Vec::new()
-			.join(&self.signed)
-			.join(&self.nonce)
-			.join(&(self.function as u8))
-			.join(&self.input_data)
-	}
-
-	fn size_of(data: &[u8]) -> Option<usize> {
-		let first_part = mem::size_of::<AccountID>() + mem::size_of::<TxOrder>() + mem::size_of::<u8>();
-		let second_part = <Vec<u8>>::size_of(&data[first_part..])?;
-		Some(first_part + second_part)
-	}
-}
-
-pub trait Hashable: Sized {
-	fn blake2_256(&self) -> [u8; 32];
-	fn twox_128(&self) -> [u8; 16];
-	fn twox_256(&self) -> [u8; 32];
-}
-
-impl<T: Slicable> Hashable for T {
-	fn blake2_256(&self) -> [u8; 32] {
-		blake2_256(&self.to_vec())
-	}
-	fn twox_128(&self) -> [u8; 16] {
-		twox_128(&self.to_vec())
-	}
-	fn twox_256(&self) -> [u8; 32] {
-		twox_256(&self.to_vec())
-	}
-}
-
-impl NonTrivialSlicable for Transaction {}
-
-/// A transactions right from the external world. Unchecked.
-pub struct UncheckedTransaction {
-	/// The actual transaction information.
-	pub transaction: Transaction,
-	/// The signature; should be an Ed25519 signature applied to the serialised `transaction` field.
-	pub signature: [u8; 64],
-}
-
-impl UncheckedTransaction {
-	/// Verify the signature.
-	pub fn ed25519_verify(&self) -> bool {
-		let msg = self.transaction.to_vec();
-		ed25519_verify(&self.signature, &msg, &self.transaction.signed)
-	}
-}
-
-#[cfg(test)]
-impl PartialEq for UncheckedTransaction {
-	fn eq(&self, other: &Self) -> bool {
-		self.signature.iter().eq(other.signature.iter()) && self.transaction == other.transaction
-	}
-}
-
-#[cfg(test)]
-impl fmt::Debug for UncheckedTransaction {
-	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-		write!(f, "UncheckedTransaction({:?})", self.transaction)
-	}
-}
-
-impl Slicable for UncheckedTransaction {
-	fn from_slice(value: &[u8]) -> Option<Self> {
-		let mut reader = StreamReader::new(value);
-		Some(UncheckedTransaction {
-			signature: reader.read()?,
-			transaction: reader.read()?,
-		})
-	}
-
-	fn set_as_slice<F: FnOnce(&mut [u8]) -> bool>(_fill_slice: F) -> Option<Self> {
-		unimplemented!();
-	}
-
-	fn to_vec(&self) -> Vec<u8> {
-		Vec::new()
-			.join(&self.signature)
-			.join(&self.transaction)
-	}
-
-	fn size_of(data: &[u8]) -> Option<usize> {
-		let first_part = mem::size_of::<[u8; 64]>();
-		let second_part = <Transaction>::size_of(&data[first_part..])?;
-		Some(first_part + second_part)
-	}
-}
-
-impl NonTrivialSlicable for UncheckedTransaction {}
-
-#[cfg_attr(test, derive(PartialEq, Debug))]
-/// A Polkadot relay chain block.
-pub struct Block {
-	/// The header of the block.
-	pub header: Header,
-	/// All transactions.
-	pub transactions: Vec<UncheckedTransaction>,
-}
-
-impl Slicable for Block {
-	fn from_slice(value: &[u8]) -> Option<Self> {
-		let mut reader = StreamReader::new(value);
-		Some(Block {
-			header: reader.read()?,
-			transactions: reader.read()?,
-		})
-	}
-
-	fn set_as_slice<F: FnOnce(&mut [u8]) -> bool>(_fill_slice: F) -> Option<Self> {
-		unimplemented!();
-	}
-
-	fn to_vec(&self) -> Vec<u8> {
-		Vec::new()
-			.join(&self.header)
-			.join(&self.transactions)
-	}
-
-	fn size_of(data: &[u8]) -> Option<usize> {
-		let first_part = Header::size_of(data)?;
-		let second_part = <Vec<Transaction>>::size_of(&data[first_part..])?;
-		Some(first_part + second_part)
-	}
-}
-
-impl NonTrivialSlicable for Block {}
-
-impl<T: Slicable> NonTrivialSlicable for Vec<T> where Vec<T>: Slicable {}
-
-impl<T: NonTrivialSlicable> Slicable for Vec<T> {
-	fn from_slice(value: &[u8]) -> Option<Self> {
-		let len = Self::size_of(&value[0..4])?;
-		let mut off = 4;
-		let mut r = Vec::new();
-		while off < len {
-			let element_len = T::size_of(&value[off..])?;
-			r.push(T::from_slice(&value[off..off + element_len])?);
-			off += element_len;
-		}
-		Some(r)
-	}
-
-	fn set_as_slice<F: FnOnce(&mut [u8]) -> bool>(_fill_slice: F) -> Option<Self> {
-		unimplemented!();
-	}
-
-	fn to_vec(&self) -> Vec<u8> {
-		let vecs = self.iter().map(Slicable::to_vec).collect::<Vec<_>>();
-		let len = vecs.iter().fold(0, |mut a, v| {a += v.len(); a});
-		let mut r = Vec::new().join(&(len as u32));
-		vecs.iter().for_each(|v| r.extend_from_slice(v));
-		r
-	}
-
-	fn size_of(data: &[u8]) -> Option<usize> {
-		u32::from_slice(&data[0..4]).map(|i| (i + 4) as usize)
-	}
-}
-
-#[cfg(test)]
-mod tests {
-	use super::*;
-	use joiner::Joiner;
-	use function::Function;
-
-	#[test]
-	fn serialise_transaction_works() {
-		let one: AccountID = [1u8; 32];
-		let two: AccountID = [2u8; 32];
-		let tx = Transaction {
-			signed: one.clone(),
-			nonce: 69,
-			function: Function::StakingTransfer,
-			input_data: Vec::new().join(&two).join(&69u64),
-		};
-		let serialised = tx.to_vec();
-		assert_eq!(serialised, vec![
-			1u8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-			69, 0, 0, 0, 0, 0, 0, 0,
-			2,
-			40, 0, 0, 0,
-				2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
-				69, 0, 0, 0, 0, 0, 0, 0
-		]);
-	}
-
-	#[test]
-	fn deserialise_transaction_works() {
-		let one: AccountID = [1u8; 32];
-		let two: AccountID = [2u8; 32];
-		let tx = Transaction {
-			signed: one.clone(),
-			nonce: 69,
-			function: Function::StakingTransfer,
-			input_data: Vec::new().join(&two).join(&69u64),
-		};
-		let data = [
-			1u8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-			69, 0, 0, 0, 0, 0, 0, 0,
-			2,
-			40, 0, 0, 0,
-				2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
-				69, 0, 0, 0, 0, 0, 0, 0
-		];
-		let deserialised = Transaction::from_slice(&data).unwrap();
-		assert_eq!(deserialised, tx);
-	}
-
-	#[test]
-	fn serialise_header_works() {
-		let h = Header {
-			parent_hash: [4u8; 32],
-			number: 42,
-			state_root: [5u8; 32],
-			transaction_root: [6u8; 32],
-			digest: Digest { logs: vec![ b"one log".to_vec(), b"another log".to_vec() ], },
-		};
-		let serialised = h.to_vec();
-		assert_eq!(serialised, vec![
-			4u8, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
-			42, 0, 0, 0, 0, 0, 0, 0,
-			5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
-			6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
-			26, 0, 0, 0,
-				7, 0, 0, 0,
-					111, 110, 101, 32, 108, 111, 103,
-				11, 0, 0, 0,
-					97, 110, 111, 116, 104, 101, 114, 32, 108, 111, 103
-		]);
-	}
-
-	#[test]
-	fn deserialise_header_works() {
-		let h = Header {
-			parent_hash: [4u8; 32],
-			number: 42,
-			state_root: [5u8; 32],
-			transaction_root: [6u8; 32],
-			digest: Digest { logs: vec![ b"one log".to_vec(), b"another log".to_vec() ], },
-		};
-		let data = [
-			4u8, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
-			42, 0, 0, 0, 0, 0, 0, 0,
-			5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
-			6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
-			26, 0, 0, 0,
-				7, 0, 0, 0,
-					111, 110, 101, 32, 108, 111, 103,
-				11, 0, 0, 0,
-					97, 110, 111, 116, 104, 101, 114, 32, 108, 111, 103
-		];
-		let deserialised = Header::from_slice(&data).unwrap();
-		assert_eq!(deserialised, h);
-	}
-
-	#[test]
-	fn serialise_block_works() {
-		let one: AccountID = [1u8; 32];
-		let two: AccountID = [2u8; 32];
-		let tx1 = UncheckedTransaction {
-			transaction: Transaction {
-				signed: one.clone(),
-				nonce: 69,
-				function: Function::StakingTransfer,
-				input_data: Vec::new().join(&two).join(&69u64),
-			},
-			signature: [1u8; 64],
-		};
-		let tx2 = UncheckedTransaction {
-			transaction: Transaction {
-				signed: two.clone(),
-				nonce: 42,
-				function: Function::StakingStake,
-				input_data: Vec::new(),
-			},
-			signature: [2u8; 64],
-		};
-		let h = Header {
-			parent_hash: [4u8; 32],
-			number: 42,
-			state_root: [5u8; 32],
-			transaction_root: [6u8; 32],
-			digest: Digest { logs: vec![ b"one log".to_vec(), b"another log".to_vec() ], },
-		};
-		let b = Block {
-			header: h,
-			transactions: vec![tx1, tx2],
-		};
-		let serialised = b.to_vec();
-		assert_eq!(serialised, vec![
-			// header
-			4u8, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
-			42, 0, 0, 0, 0, 0, 0, 0,
-			5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
-			6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
-			26, 0, 0, 0,
-				7, 0, 0, 0,
-					111, 110, 101, 32, 108, 111, 103,
-				11, 0, 0, 0,
-					97, 110, 111, 116, 104, 101, 114, 32, 108, 111, 103,
-			// transactions
-			2, 1, 0, 0,
-				// tx1
-				1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-				1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-				69, 0, 0, 0, 0, 0, 0, 0,
-				2,
-				40, 0, 0, 0,
-					2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
-					69, 0, 0, 0, 0, 0, 0, 0,
-				// tx2
-				2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
-				2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
-				42, 0, 0, 0, 0, 0, 0, 0,
-				0,
-				0, 0, 0, 0
-		]);
-	}
-
-	#[test]
-	fn deserialise_block_works() {
-		let one: AccountID = [1u8; 32];
-		let two: AccountID = [2u8; 32];
-		let tx1 = UncheckedTransaction {
-			transaction: Transaction {
-				signed: one.clone(),
-				nonce: 69,
-				function: Function::StakingTransfer,
-				input_data: Vec::new().join(&two).join(&69u64),
-			},
-			signature: [1u8; 64],
-		};
-		let tx2 = UncheckedTransaction {
-			transaction: Transaction {
-				signed: two.clone(),
-				nonce: 42,
-				function: Function::StakingStake,
-				input_data: Vec::new(),
-			},
-			signature: [2u8; 64],
-		};
-		let h = Header {
-			parent_hash: [4u8; 32],
-			number: 42,
-			state_root: [5u8; 32],
-			transaction_root: [6u8; 32],
-			digest: Digest { logs: vec![ b"one log".to_vec(), b"another log".to_vec() ], },
-		};
-		let b = Block {
-			header: h,
-			transactions: vec![tx1, tx2],
-		};
-		let data = [
-			// header
-			4u8, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
-			42, 0, 0, 0, 0, 0, 0, 0,
-			5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
-			6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
-			26, 0, 0, 0,
-				7, 0, 0, 0,
-					111, 110, 101, 32, 108, 111, 103,
-				11, 0, 0, 0,
-					97, 110, 111, 116, 104, 101, 114, 32, 108, 111, 103,
-			// transactions
-			2, 1, 0, 0,
-				// tx1
-				1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-				1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-				69, 0, 0, 0, 0, 0, 0, 0,
-				2,
-				40, 0, 0, 0,
-					2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
-					69, 0, 0, 0, 0, 0, 0, 0,
-				// tx2
-				2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
-				2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
-				42, 0, 0, 0, 0, 0, 0, 0,
-				0,
-				0, 0, 0, 0
-		];
-		let deserialised = Block::from_slice(&data).unwrap();
-		assert_eq!(deserialised, b);
-	}
-}
diff --git a/substrate/wasm-runtime/polkadot/src/support/statichex.rs b/substrate/wasm-runtime/polkadot/src/support/statichex.rs
index 152ceadc0b..b750a8ca10 100644
--- a/substrate/wasm-runtime/polkadot/src/support/statichex.rs
+++ b/substrate/wasm-runtime/polkadot/src/support/statichex.rs
@@ -36,7 +36,16 @@ macro_rules! impl_sizes {
 	)* }
 }
 
-impl_sizes!(1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 20, 24, 28, 32, 40, 48, 56, 64, 80, 96, 112, 128);
+impl StaticHexConversion for Vec<u8> {
+	fn from_static_hex(hex: &'static str) -> Self {
+		FromHex::from_hex(hex).unwrap()
+	}
+}
+
+impl_sizes!(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
+	17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
+	33, 34, 35, 36, 37, 38, 39, 40, 451, 42, 43, 44, 45, 46, 47, 48,
+	56, 64, 80, 96, 112, 128);
 
 /// Trait to allow converting from itself (only implemented for a static str) into some useful
 /// type (which must implement `StaticHexConversion`).
diff --git a/substrate/wasm-runtime/polkadot/src/support/storable.rs b/substrate/wasm-runtime/polkadot/src/support/storable.rs
deleted file mode 100644
index 9a871a638b..0000000000
--- a/substrate/wasm-runtime/polkadot/src/support/storable.rs
+++ /dev/null
@@ -1,88 +0,0 @@
-// Copyright 2017 Parity Technologies (UK) Ltd.
-// This file is part of Polkadot.
-
-// Polkadot 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.
-
-// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
-
-//! Stuff to do with the runtime's storage.
-
-use slicable::Slicable;
-use endiansensitive::EndianSensitive;
-use keyedvec::KeyedVec;
-use runtime_support::prelude::*;
-use runtime_support::{self, twox_128};
-
-/// Trait for a value which may be stored in the storage DB.
-pub trait Storable {
-	/// Lookup the value in storage and deserialise, giving a default value if not found.
-	fn lookup_default(key: &[u8]) -> Self where Self: Sized + Default { Self::lookup(key).unwrap_or_else(Default::default) }
-	/// Lookup `Some` value in storage and deserialise; `None` if it's not there.
-	fn lookup(_key: &[u8]) -> Option<Self> where Self: Sized { unimplemented!() }
-	/// Place the value in storage under `key`.
-	fn store(&self, key: &[u8]);
-}
-
-// TODO: consider using blake256 to avoid possible eclipse attack.
-
-/// Remove `key` from storage.
-pub fn kill(key: &[u8]) { runtime_support::set_storage(&twox_128(key)[..], b""); }
-
-impl<T: Default + EndianSensitive> Storable for T {
-	fn lookup(key: &[u8]) -> Option<Self> {
-		Slicable::set_as_slice(|out| runtime_support::read_storage(&twox_128(key)[..], out) == out.len())
-	}
-	fn store(&self, key: &[u8]) {
-		self.as_slice_then(|slice| runtime_support::set_storage(&twox_128(key)[..], slice));
-	}
-}
-
-impl Storable for [u8] {
-	fn store(&self, key: &[u8]) {
-		runtime_support::set_storage(&twox_128(key)[..], self)
-	}
-}
-
-/// A trait to conveniently store a vector of storable data.
-// TODO: add iterator support
-pub trait StorageVec {
-	type Item: Default + Sized + Storable;
-	const PREFIX: &'static [u8];
-
-	/// Get the current set of items.
-	fn items() -> Vec<Self::Item> {
-		(0..Self::count()).into_iter().map(Self::item).collect()
-	}
-
-	/// Set the current set of items.
-	fn set_items(items: &[Self::Item]) {
-		Self::set_count(items.len() as u32);
-		items.iter().enumerate().for_each(|(v, ref i)| Self::set_item(v as u32, i));
-	}
-
-	fn set_item(index: u32, item: &Self::Item) {
-		item.store(&index.to_keyed_vec(Self::PREFIX));
-	}
-
-	fn item(index: u32) -> Self::Item {
-		Storable::lookup_default(&index.to_keyed_vec(Self::PREFIX))
-	}
-
-	fn set_count(count: u32) {
-		(count..Self::count()).for_each(|i| Self::set_item(i, &Self::Item::default()));
-		count.store(&b"len".to_keyed_vec(Self::PREFIX));
-	}
-
-	fn count() -> u32 {
-		Storable::lookup_default(&b"len".to_keyed_vec(Self::PREFIX))
-	}
-}
diff --git a/substrate/wasm-runtime/polkadot/src/support/storage.rs b/substrate/wasm-runtime/polkadot/src/support/storage.rs
new file mode 100644
index 0000000000..3ff8b1c75d
--- /dev/null
+++ b/substrate/wasm-runtime/polkadot/src/support/storage.rs
@@ -0,0 +1,229 @@
+// Copyright 2017 Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot 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.
+
+// Polkadot 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 Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Stuff to do with the runtime's storage.
+
+use runtime_std::prelude::*;
+use runtime_std::{self, twox_128};
+use codec::{Slicable, KeyedVec};
+
+// TODO: consider using blake256 to avoid possible preimage attack.
+
+/// Return the value of the item in storage under `key`, or `None` if there is no explicit entry.
+pub fn get<T: Slicable + Sized>(key: &[u8]) -> Option<T> {
+	Slicable::set_as_slice(&|out, offset|
+		runtime_std::read_storage(&twox_128(key)[..], out, offset) >= out.len()
+	)
+}
+
+/// Return the value of the item in storage under `key`, or the type's default if there is no
+/// explicit entry.
+pub fn get_or_default<T: Slicable + Sized + Default>(key: &[u8]) -> T {
+	get(key).unwrap_or_else(Default::default)
+}
+
+/// Return the value of the item in storage under `key`, or `default_value` if there is no
+/// explicit entry.
+pub fn get_or<T: Slicable + Sized>(key: &[u8], default_value: T) -> T {
+	get(key).unwrap_or(default_value)
+}
+
+/// Return the value of the item in storage under `key`, or `default_value()` if there is no
+/// explicit entry.
+pub fn get_or_else<T: Slicable + Sized, F: FnOnce() -> T>(key: &[u8], default_value: F) -> T {
+	get(key).unwrap_or_else(default_value)
+}
+
+/// Please `value` in storage under `key`.
+pub fn put<T: Slicable>(key: &[u8], value: &T) {
+	value.as_slice_then(|slice| runtime_std::set_storage(&twox_128(key)[..], slice));
+}
+
+/// Please `value` in storage under `key`.
+pub fn place<T: Slicable>(key: &[u8], value: T) {
+	value.as_slice_then(|slice| runtime_std::set_storage(&twox_128(key)[..], slice));
+}
+
+/// Remove `key` from storage, returning its value if it had an explicit entry or `None` otherwise.
+pub fn take<T: Slicable + Sized>(key: &[u8]) -> Option<T> {
+	let r = get(key);
+	if r.is_some() {
+		kill(key);
+	}
+	r
+}
+
+/// Remove `key` from storage, returning its value, or, if there was no explicit entry in storage,
+/// the default for its type.
+pub fn take_or_default<T: Slicable + Sized + Default>(key: &[u8]) -> T {
+	take(key).unwrap_or_else(Default::default)
+}
+
+/// Return the value of the item in storage under `key`, or `default_value` if there is no
+/// explicit entry. Ensure there is no explicit entry on return.
+pub fn take_or<T: Slicable + Sized>(key: &[u8], default_value: T) -> T {
+	take(key).unwrap_or(default_value)
+}
+
+/// Return the value of the item in storage under `key`, or `default_value()` if there is no
+/// explicit entry. Ensure there is no explicit entry on return.
+pub fn take_or_else<T: Slicable + Sized, F: FnOnce() -> T>(key: &[u8], default_value: F) -> T {
+	take(key).unwrap_or_else(default_value)
+}
+
+/// Check to see if `key` has an explicit entry in storage.
+pub fn exists(key: &[u8]) -> bool {
+	let mut x = [0u8; 1];
+	runtime_std::read_storage(&twox_128(key)[..], &mut x[..], 0) >= 1
+}
+
+/// Ensure `key` has no explicit entry in storage.
+pub fn kill(key: &[u8]) {
+	runtime_std::set_storage(&twox_128(key)[..], b"");
+}
+
+/// Get a Vec of bytes from storage.
+pub fn get_raw(key: &[u8]) -> Vec<u8> {
+	runtime_std::storage(&twox_128(key)[..])
+}
+
+/// Put a raw byte slice into storage.
+pub fn put_raw(key: &[u8], value: &[u8]) {
+	runtime_std::set_storage(&twox_128(key)[..], value)
+}
+
+/// A trait to conveniently store a vector of storable data.
+// TODO: add iterator support
+pub trait StorageVec {
+	type Item: Default + Sized + Slicable;
+	const PREFIX: &'static [u8];
+
+	/// Get the current set of items.
+	fn items() -> Vec<Self::Item> {
+		(0..Self::count()).into_iter().map(Self::item).collect()
+	}
+
+	/// Set the current set of items.
+	fn set_items(items: &[Self::Item]) {
+		Self::set_count(items.len() as u32);
+		items.iter().enumerate().for_each(|(v, ref i)| Self::set_item(v as u32, i));
+	}
+
+	fn set_item(index: u32, item: &Self::Item) {
+		if index < Self::count() {
+			put(&index.to_keyed_vec(Self::PREFIX), item);
+		}
+	}
+
+	fn item(index: u32) -> Self::Item {
+		get_or_default(&index.to_keyed_vec(Self::PREFIX))
+	}
+
+	fn set_count(count: u32) {
+		(count..Self::count()).for_each(|i| Self::set_item(i, &Self::Item::default()));
+		put(&b"len".to_keyed_vec(Self::PREFIX), &count);
+	}
+
+	fn count() -> u32 {
+		get_or_default(&b"len".to_keyed_vec(Self::PREFIX))
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use std::collections::HashMap;
+	use runtime_std::with_externalities;
+	use support::{TestExternalities, HexDisplay};
+	use runtime_std::{storage, twox_128};
+
+	#[test]
+	fn integers_can_be_stored() {
+		let mut t = TestExternalities { storage: HashMap::new(), };
+		with_externalities(&mut t, || {
+			let x = 69u32;
+			put(b":test", &x);
+			let y: u32 = get(b":test").unwrap();
+			assert_eq!(x, y);
+		});
+		with_externalities(&mut t, || {
+			let x = 69426942i64;
+			put(b":test", &x);
+			let y: i64 = get(b":test").unwrap();
+			assert_eq!(x, y);
+		});
+	}
+
+	#[test]
+	fn bools_can_be_stored() {
+		let mut t = TestExternalities { storage: HashMap::new(), };
+		with_externalities(&mut t, || {
+			let x = true;
+			put(b":test", &x);
+			let y: bool = get(b":test").unwrap();
+			assert_eq!(x, y);
+		});
+
+		with_externalities(&mut t, || {
+			let x = false;
+			put(b":test", &x);
+			let y: bool = get(b":test").unwrap();
+			assert_eq!(x, y);
+		});
+	}
+
+	#[test]
+	fn vecs_can_be_retrieved() {
+		let mut t = TestExternalities { storage: HashMap::new(), };
+		with_externalities(&mut t, || {
+			runtime_std::set_storage(&twox_128(b":test"), b"\x0b\0\0\0Hello world");
+			let x = b"Hello world".to_vec();
+			println!("Hex: {}", HexDisplay::from(&storage(&twox_128(b":test"))));
+			let y = get::<Vec<u8>>(b":test").unwrap();
+			assert_eq!(x, y);
+
+		});
+	}
+
+	#[test]
+	fn vecs_can_be_stored() {
+		let mut t = TestExternalities { storage: HashMap::new(), };
+		let x = b"Hello world".to_vec();
+
+		with_externalities(&mut t, || {
+			put(b":test", &x);
+		});
+
+		println!("Ext is {:?}", t);
+		with_externalities(&mut t, || {
+			println!("Hex: {}", HexDisplay::from(&storage(&twox_128(b":test"))));
+			let y: Vec<u8> = get(b":test").unwrap();
+			assert_eq!(x, y);
+		});
+	}
+
+	#[test]
+	fn proposals_can_be_stored() {
+		use primitives::{Proposal, InternalFunction};
+		let mut t = TestExternalities { storage: HashMap::new(), };
+		with_externalities(&mut t, || {
+			let x = Proposal { function: InternalFunction::StakingSetSessionsPerEra, input_data: b"Hello world".to_vec() };
+			put(b":test", &x);
+			let y: Proposal = get(b":test").unwrap();
+			assert_eq!(x, y);
+		});
+	}
+}
diff --git a/substrate/wasm-runtime/polkadot/src/support/testing.rs b/substrate/wasm-runtime/polkadot/src/support/testing.rs
index e2e7b40562..e0e1a336c8 100644
--- a/substrate/wasm-runtime/polkadot/src/support/testing.rs
+++ b/substrate/wasm-runtime/polkadot/src/support/testing.rs
@@ -16,10 +16,10 @@
 
 //! Testing helpers.
 
-use runtime_support::{NoError, Externalities};
 use std::collections::HashMap;
+use runtime_std::{Externalities, ExternalitiesError};
 use primitives::AccountID;
-use statichex::StaticHexInto;
+use super::statichex::StaticHexInto;
 
 #[derive(Debug, Default)]
 /// Simple externaties implementation.
@@ -29,9 +29,7 @@ pub struct TestExternalities {
 }
 
 impl Externalities for TestExternalities {
-	type Error = NoError;
-
-	fn storage(&self, key: &[u8]) -> Result<&[u8], NoError> {
+	fn storage(&self, key: &[u8]) -> Result<&[u8], ExternalitiesError> {
 		Ok(self.storage.get(&key.to_vec()).map_or(&[] as &[u8], Vec::as_slice))
 	}
 
diff --git a/substrate/wasm-runtime/pwasm-libc/src/lib.rs b/substrate/wasm-runtime/pwasm-libc/src/lib.rs
index eed597e73b..f4e5eb7a57 100644
--- a/substrate/wasm-runtime/pwasm-libc/src/lib.rs
+++ b/substrate/wasm-runtime/pwasm-libc/src/lib.rs
@@ -8,6 +8,7 @@ extern "C" {
 	fn ext_memcpy(dest: *mut u8, src: *const u8, n: usize) -> *mut u8;
 	fn ext_memmove(dest: *mut u8, src: *const u8, n: usize) -> *mut u8;
 	fn ext_memset(dest: *mut u8, c: i32, n: usize) -> *mut u8;
+	fn ext_memcmp(s1: *const u8, s2: *const u8, n: usize) -> i32;
 	fn ext_malloc(size: usize) -> *mut u8;
 	fn ext_free(ptr: *mut u8);
 }
@@ -21,6 +22,12 @@ pub unsafe extern "C" fn memcpy(dest: *mut u8, src: *const u8, n: usize) -> *mut
 	ext_memcpy(dest, src, n)
 }
 
+/// memcmp extern
+#[no_mangle]
+pub unsafe extern "C" fn memcmp(s1: *const u8, s2: *const u8, n: usize) -> i32 {
+	ext_memcmp(s1, s2, n)
+}
+
 /// memmove extern
 #[no_mangle]
 pub unsafe extern "C" fn memmove(dest: *mut u8, src: *const u8, n: usize) -> *mut u8 {
diff --git a/substrate/wasm-runtime/support/Cargo.toml b/substrate/wasm-runtime/std/Cargo.toml
similarity index 90%
rename from substrate/wasm-runtime/support/Cargo.toml
rename to substrate/wasm-runtime/std/Cargo.toml
index 828fdab534..802d1fabde 100644
--- a/substrate/wasm-runtime/support/Cargo.toml
+++ b/substrate/wasm-runtime/std/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "runtime-support"
+name = "runtime-std"
 version = "0.1.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 
diff --git a/substrate/wasm-runtime/support/src/lib.rs b/substrate/wasm-runtime/std/src/lib.rs
similarity index 55%
rename from substrate/wasm-runtime/support/src/lib.rs
rename to substrate/wasm-runtime/std/src/lib.rs
index 90c59a6e74..9b7d385e69 100644
--- a/substrate/wasm-runtime/support/src/lib.rs
+++ b/substrate/wasm-runtime/std/src/lib.rs
@@ -1,9 +1,9 @@
 #![no_std]
 #![feature(lang_items)]
+#![feature(core_intrinsics)]
 #![feature(alloc)]
 #![cfg_attr(feature = "strict", deny(warnings))]
 
-#![feature(alloc)]
 extern crate alloc;
 
 pub use alloc::vec;
@@ -26,16 +26,22 @@ extern crate pwasm_alloc;
 
 #[lang = "panic_fmt"]
 #[no_mangle]
-pub fn panic_fmt() -> ! {
-	  loop {}
+pub extern fn panic_fmt(_fmt: ::core::fmt::Arguments, _file: &'static str, _line: u32, _col: u32) {
+	unsafe {
+		ext_print_utf8(_file.as_ptr() as *const u8, _file.len() as u32);
+		ext_print_num(_line as u64);
+		ext_print_num(_col as u64);
+		::core::intrinsics::abort()
+	}
 }
 
 extern "C" {
-	fn ext_print(utf8_data: *const u8, utf8_len: u32);
+	fn ext_print_utf8(utf8_data: *const u8, utf8_len: u32);
+	fn ext_print_hex(data: *const u8, len: u32);
 	fn ext_print_num(value: u64);
 	fn ext_set_storage(key_data: *const u8, key_len: u32, value_data: *const u8, value_len: u32);
 	fn ext_get_allocated_storage(key_data: *const u8, key_len: u32, written_out: *mut u32) -> *mut u8;
-	fn ext_get_storage_into(key_data: *const u8, key_len: u32, value_data: *mut u8, value_len: u32) -> u32;
+	fn ext_get_storage_into(key_data: *const u8, key_len: u32, value_data: *mut u8, value_len: u32, value_offset: u32) -> u32;
 	fn ext_chain_id() -> u64;
 	fn ext_blake2_256(data: *const u8, len: u32, out: *mut u8);
 	fn ext_twox_128(data: *const u8, len: u32, out: *mut u8);
@@ -46,7 +52,7 @@ extern "C" {
 pub fn storage(key: &[u8]) -> Vec<u8> {
 	let mut length: u32 = 0;
 	unsafe {
-		let ptr = ext_get_allocated_storage(&key[0], key.len() as u32, &mut length);
+		let ptr = ext_get_allocated_storage(key.as_ptr(), key.len() as u32, &mut length);
 		Vec::from_raw_parts(ptr, length as usize, length as usize)
 	}
 }
@@ -54,15 +60,15 @@ pub fn storage(key: &[u8]) -> Vec<u8> {
 pub fn set_storage(key: &[u8], value: &[u8]) {
 	unsafe {
 		ext_set_storage(
-			&key[0] as *const u8, key.len() as u32,
-			&value[0] as *const u8, value.len() as u32
+			key.as_ptr(), key.len() as u32,
+			value.as_ptr(), value.len() as u32
 		);
 	}
 }
 
-pub fn read_storage(key: &[u8], value_out: &mut [u8]) -> usize {
+pub fn read_storage(key: &[u8], value_out: &mut [u8], value_offset: usize) -> usize {
 	unsafe {
-		ext_get_storage_into(&key[0], key.len() as u32, &mut value_out[0], value_out.len() as u32) as usize
+		ext_get_storage_into(key.as_ptr(), key.len() as u32, value_out.as_mut_ptr(), value_out.len() as u32, value_offset as u32) as usize
 	}
 }
 
@@ -75,38 +81,38 @@ pub fn chain_id() -> u64 {
 
 /// Conduct a 256-bit Blake2 hash.
 pub fn blake2_256(data: &[u8]) -> [u8; 32] {
+	let mut result: [u8; 32] = Default::default();
+	// guaranteed to write into result.
 	unsafe {
-		let mut result: [u8; 32] = Default::default();
-		// guaranteed to write into result.
-		ext_blake2_256(&data[0], data.len() as u32, &mut result[0]);
-		result
+		ext_blake2_256(data.as_ptr(), data.len() as u32, result.as_mut_ptr());
 	}
+	result
 }
 
 /// Conduct four XX hashes to give a 256-bit result.
 pub fn twox_256(data: &[u8]) -> [u8; 32] {
+	let mut result: [u8; 32] = Default::default();
+	// guaranteed to write into result.
 	unsafe {
-		let mut result: [u8; 32] = Default::default();
-		// guaranteed to write into result.
-		ext_twox_256(&data[0], data.len() as u32, &mut result[0]);
-		result
+		ext_twox_256(data.as_ptr(), data.len() as u32, result.as_mut_ptr());
 	}
+	result
 }
 
-/// Conduct two XX hashes to give a 256-bit result.
+/// Conduct two XX hashes to give a 128-bit result.
 pub fn twox_128(data: &[u8]) -> [u8; 16] {
+	let mut result: [u8; 16] = Default::default();
+	// guaranteed to write into result.
 	unsafe {
-		let mut result: [u8; 16] = Default::default();
-		// guaranteed to write into result.
-		ext_twox_128(&data[0], data.len() as u32, &mut result[0]);
-		result
+		ext_twox_128(data.as_ptr(), data.len() as u32, result.as_mut_ptr());
 	}
+	result
 }
 
 /// Verify a ed25519 signature.
 pub fn ed25519_verify(sig: &[u8], msg: &[u8], pubkey: &[u8]) -> bool {
-	sig.len() != 64 || pubkey.len() != 32 || unsafe {
-		ext_ed25519_verify(&msg[0], msg.len() as u32, &sig[0], &pubkey[0])
+	sig.len() == 64 && pubkey.len() == 32 && unsafe {
+		ext_ed25519_verify(msg.as_ptr(), msg.len() as u32, sig.as_ptr(), pubkey.as_ptr())
 	} == 0
 }
 
@@ -117,7 +123,15 @@ pub trait Printable {
 impl<'a> Printable for &'a [u8] {
 	fn print(self) {
 		unsafe {
-			ext_print(self.as_ptr(), self.len() as u32);
+			ext_print_hex(self.as_ptr(), self.len() as u32);
+		}
+	}
+}
+
+impl<'a> Printable for &'a str {
+	fn print(self) {
+		unsafe {
+			ext_print_utf8(self.as_ptr() as *const u8, self.len() as u32);
 		}
 	}
 }
@@ -139,12 +153,16 @@ macro_rules! impl_stubs {
 			$(
 				#[no_mangle]
 				pub fn $name(input_data: *mut u8, input_len: usize) -> u64 {
-					let input = unsafe {
-						$crate::vec::Vec::from_raw_parts(input_data, input_len, input_len)
+					let input = if input_len == 0 {
+						&[0u8; 0]
+					} else {
+						unsafe {
+							$crate::slice::from_raw_parts(input_data, input_len)
+						}
 					};
 
 					let output = super::$name(input);
-					&output[0] as *const u8 as u64 + ((output.len() as u64) << 32)
+					output.as_ptr() as u64 + ((output.len() as u64) << 32)
 				}
 			)*
 		}
diff --git a/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.compact.wasm b/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.compact.wasm
index c1051d3414..db7dab9917 100644
Binary files a/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.compact.wasm and b/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.compact.wasm differ
diff --git a/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.wasm b/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.wasm
index 231fa8af91..a0dc5a2754 100644
Binary files a/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.wasm and b/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_polkadot.wasm differ
diff --git a/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.compact.wasm b/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.compact.wasm
index b1357890d8..63e7666aad 100644
Binary files a/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.compact.wasm and b/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.compact.wasm differ
diff --git a/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.wasm b/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.wasm
index 646b019bc0..c1b257f3a3 100644
Binary files a/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.wasm and b/substrate/wasm-runtime/target/wasm32-unknown-unknown/release/runtime_test.wasm differ
diff --git a/substrate/wasm-runtime/test/Cargo.toml b/substrate/wasm-runtime/test/Cargo.toml
index 57015d2683..c7191fb805 100644
--- a/substrate/wasm-runtime/test/Cargo.toml
+++ b/substrate/wasm-runtime/test/Cargo.toml
@@ -7,4 +7,4 @@ authors = ["Parity Technologies <admin@parity.io>"]
 crate-type = ["cdylib"]
 
 [dependencies]
-runtime-support = { path = "../support", version = "0.1" }
+runtime-std = { path = "../std", version = "0.1" }
diff --git a/substrate/wasm-runtime/test/src/lib.rs b/substrate/wasm-runtime/test/src/lib.rs
index 1cf1934976..c63ca73fca 100644
--- a/substrate/wasm-runtime/test/src/lib.rs
+++ b/substrate/wasm-runtime/test/src/lib.rs
@@ -7,40 +7,56 @@ extern crate alloc;
 use alloc::vec::Vec;
 
 #[macro_use]
-extern crate runtime_support;
-use runtime_support::{set_storage, storage, print, blake2_256, twox_128, twox_256, ed25519_verify};
+extern crate runtime_std;
+use runtime_std::{set_storage, storage, print, blake2_256, twox_128, twox_256, ed25519_verify};
 
-fn test_blake2_256(input: Vec<u8>) -> Vec<u8> {
+fn test_blake2_256(input: &[u8]) -> Vec<u8> {
 	blake2_256(&input).to_vec()
 }
 
-fn test_twox_256(input: Vec<u8>) -> Vec<u8> {
+fn test_twox_256(input: &[u8]) -> Vec<u8> {
 	twox_256(&input).to_vec()
 }
 
-fn test_twox_128(input: Vec<u8>) -> Vec<u8> {
+fn test_twox_128(input: &[u8]) -> Vec<u8> {
 	twox_128(&input).to_vec()
 }
 
-fn test_ed25519_verify(input: Vec<u8>) -> Vec<u8> {
+fn test_ed25519_verify(input: &[u8]) -> Vec<u8> {
 	let sig = &input[0..64];
 	let pubkey = &input[64..96];
 	let msg = b"all ok!";
 	[ed25519_verify(sig, &msg[..], pubkey) as u8].to_vec()
 }
 
-fn test_data_in(input: Vec<u8>) -> Vec<u8> {
-	print(b"set_storage" as &[u8]);
+fn test_data_in(input: &[u8]) -> Vec<u8> {
+	print("set_storage");
 	set_storage(b"input", &input);
 
-	print(b"storage" as &[u8]);
+	print("storage");
 	let foo = storage(b"foo");
 
-	print(b"set_storage" as &[u8]);
+	print("set_storage");
 	set_storage(b"baz", &foo);
 
-	print(b"finished!" as &[u8]);
+	print("finished!");
 	b"all ok!".to_vec()
 }
 
-impl_stubs!(test_data_in, test_blake2_256, test_twox_256, test_twox_128, test_ed25519_verify);
+fn test_empty_return(_input: &[u8]) -> Vec<u8> {
+	Vec::new()
+}
+
+fn test_panic(_input: &[u8]) -> Vec<u8> {
+	panic!("test panic");
+}
+
+fn test_conditional_panic(input: &[u8]) -> Vec<u8> {
+	if input.len() > 0 {
+		panic!("test panic");
+	}
+	input.to_vec()
+}
+
+impl_stubs!(test_data_in, test_empty_return, test_panic, test_conditional_panic,
+	test_blake2_256, test_twox_256, test_twox_128, test_ed25519_verify);