diff --git a/substrate/Cargo.lock b/substrate/Cargo.lock
index 32eb742442..993b4bdd6b 100644
--- a/substrate/Cargo.lock
+++ b/substrate/Cargo.lock
@@ -1804,6 +1804,7 @@ dependencies = [
  "srml-treasury 0.1.0",
  "srml-upgrade-key 0.1.0",
  "substrate-client 0.1.0",
+ "substrate-fg-primitives 0.1.0",
  "substrate-keyring 0.1.0",
  "substrate-primitives 0.1.0",
 ]
@@ -3186,6 +3187,7 @@ dependencies = [
  "parity-codec 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "parity-codec-derive 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "sr-primitives 0.1.0",
+ "sr-std 0.1.0",
  "substrate-client 0.1.0",
  "substrate-primitives 0.1.0",
 ]
diff --git a/substrate/core/finality-grandpa/primitives/Cargo.toml b/substrate/core/finality-grandpa/primitives/Cargo.toml
index 2b2711fab8..8f9c6628b8 100644
--- a/substrate/core/finality-grandpa/primitives/Cargo.toml
+++ b/substrate/core/finality-grandpa/primitives/Cargo.toml
@@ -9,6 +9,7 @@ substrate-primitives = { path = "../../primitives", default-features = false }
 parity-codec = { version = "2.1", default-features = false }
 parity-codec-derive = { version = "2.1", default-features = false }
 sr-primitives = { path = "../../sr-primitives", default-features = false }
+sr-std = { path = "../../sr-std", default-features = false }
 
 [features]
 default = ["std"]
@@ -18,4 +19,5 @@ std = [
 	"parity-codec/std",
 	"parity-codec-derive/std",
 	"sr-primitives/std",
+	"sr-std/std",
 ]
diff --git a/substrate/core/finality-grandpa/primitives/src/lib.rs b/substrate/core/finality-grandpa/primitives/src/lib.rs
index ed8ae408b7..aaca423ecd 100644
--- a/substrate/core/finality-grandpa/primitives/src/lib.rs
+++ b/substrate/core/finality-grandpa/primitives/src/lib.rs
@@ -28,8 +28,11 @@ extern crate parity_codec_derive;
 #[macro_use]
 extern crate substrate_client as client;
 
+extern crate sr_std as rstd;
+
 use substrate_primitives::AuthorityId;
 use sr_primitives::traits::{Block as BlockT, DigestFor, NumberFor};
+use rstd::vec::Vec;
 
 /// A scheduled change of authority set.
 #[cfg_attr(feature = "std", derive(Debug, PartialEq))]
@@ -81,55 +84,3 @@ decl_runtime_apis! {
 		fn grandpa_authorities() -> Vec<(AuthorityId, u64)>;
 	}
 }
-
-#[cfg(feature = "std")]
-mod implementation {
-	use super::{GrandpaApi, ScheduledChange};
-	use sr_primitives::traits::{Block as BlockT, DigestFor, NumberFor};
-	use sr_primitives::generic::BlockId;
-	use parity_codec::{Encode, Decode};
-	use client::{Client, error::Error as ClientError, backend::Backend, CallExecutor};
-	use client::runtime_api::{CallApiAt, Core as CoreAPI};
-	use substrate_primitives::{AuthorityId, H256, Blake2Hasher};
-
-	// TODO [basti]: do this implementation in runtime.
-	impl<B, E, Block: BlockT<Hash=H256>, RA> GrandpaApi<Block> for Client<B, E, Block, RA> where
-		B: Backend<Block, Blake2Hasher> + 'static,
-		E: CallExecutor<Block, Blake2Hasher> + 'static + Clone + Send + Sync,
-		DigestFor<Block>: Encode,
-		RA: CoreAPI<Block>,
-	{
-		fn grandpa_authorities(&self, at: &BlockId<Block>) -> Result<Vec<(AuthorityId, u64)>, ClientError> {
-			let raw = self.call_api_at(
-				&at,
-				::AUTHORITIES_CALL,
-				Encode::encode(&()),
-				&mut Default::default(),
-				&mut None,
-			);
-
-			// TODO [basti]: implement this in runtime with macro.
-			match Decode::decode(&mut &raw[..]) {
-				Some(x) => Ok(x),
-				None => Err(::client::error::ErrorKind::CallResultDecode(::AUTHORITIES_CALL).into()),
-			}
-		}
-
-		fn grandpa_pending_change(&self, at: &BlockId<Block>, digest: DigestFor<Block>)
-			-> Result<Option<ScheduledChange<NumberFor<Block>>>, ClientError>
-		{
-			let raw = self.call_api_at(
-				at,
-				::PENDING_CHANGE_CALL,
-				digest.encode(),
-				&mut Default::default(),
-				&mut None,
-			);
-
-			match Decode::decode(&mut &raw[..]) {
-				Some(x) => Ok(x),
-				None => Err(::client::error::ErrorKind::CallResultDecode(::PENDING_CHANGE_CALL).into()),
-			}
-		}
-	}
-}
diff --git a/substrate/core/finality-grandpa/src/lib.rs b/substrate/core/finality-grandpa/src/lib.rs
index 1a0f10334a..b107c3089e 100644
--- a/substrate/core/finality-grandpa/src/lib.rs
+++ b/substrate/core/finality-grandpa/src/lib.rs
@@ -84,11 +84,11 @@ use futures::stream::Fuse;
 use futures::sync::mpsc;
 use client::{Client, error::Error as ClientError, ImportNotifications, backend::Backend, CallExecutor};
 use client::blockchain::HeaderBackend;
-use client::runtime_api::{CallApiAt, TaggedTransactionQueue, Core as CoreAPI};
+use client::runtime_api::TaggedTransactionQueue;
 use codec::{Encode, Decode};
 use consensus_common::{BlockImport, ImportBlock, ImportResult};
 use runtime_primitives::traits::{
-	NumberFor, Block as BlockT, Header as HeaderT, DigestFor,
+	NumberFor, Block as BlockT, Header as HeaderT, DigestFor, ProvideRuntimeApi
 };
 use fg_primitives::GrandpaApi;
 use runtime_primitives::generic::BlockId;
@@ -773,18 +773,16 @@ impl<B, E, Block: BlockT<Hash=H256>, N, RA> voter::Environment<Block::Hash, Numb
 /// This scans each imported block for signals of changing authority set.
 /// When using GRANDPA, the block import worker should be using this block import
 /// object.
-pub struct GrandpaBlockImport<B, E, Block: BlockT<Hash=H256>, Api, RA> {
+pub struct GrandpaBlockImport<B, E, Block: BlockT<Hash=H256>, RA> {
 	inner: Arc<Client<B, E, Block, RA>>,
 	authority_set: SharedAuthoritySet<Block::Hash, NumberFor<Block>>,
-	api_client: Api,
 }
 
-impl<B, E, Block: BlockT<Hash=H256>, Api, RA> BlockImport<Block> for GrandpaBlockImport<B, E, Block, Api, RA> where
+impl<B, E, Block: BlockT<Hash=H256>, RA> BlockImport<Block> for GrandpaBlockImport<B, E, Block, RA> where
 	B: Backend<Block, Blake2Hasher> + 'static,
 	E: CallExecutor<Block, Blake2Hasher> + 'static + Clone + Send + Sync,
 	DigestFor<Block>: Encode,
-	Api: GrandpaApi<Block>,
-	RA: TaggedTransactionQueue<Block> + Send + Sync, // necessary for client to import `BlockImport`.
+	RA: GrandpaApi<Block> + TaggedTransactionQueue<Block>,
 {
 	type Error = ClientError;
 
@@ -793,7 +791,7 @@ impl<B, E, Block: BlockT<Hash=H256>, Api, RA> BlockImport<Block> for GrandpaBloc
 	{
 		use authorities::PendingChange;
 
-		let maybe_change = self.api_client.grandpa_pending_change(
+		let maybe_change = self.inner.runtime_api().grandpa_pending_change(
 			&BlockId::hash(*block.header.parent_hash()),
 			&block.header.digest().clone(),
 		)?;
@@ -839,13 +837,12 @@ pub struct LinkHalf<B, E, Block: BlockT<Hash=H256>, RA> {
 
 /// Make block importer and link half necessary to tie the background voter
 /// to it.
-pub fn block_import<B, E, Block: BlockT<Hash=H256>, Api, RA>(client: Arc<Client<B, E, Block, RA>>, api_client: Api)
-	-> Result<(GrandpaBlockImport<B, E, Block, Api, RA>, LinkHalf<B, E, Block, RA>), ClientError>
+pub fn block_import<B, E, Block: BlockT<Hash=H256>, RA>(client: Arc<Client<B, E, Block, RA>>)
+	-> Result<(GrandpaBlockImport<B, E, Block, RA>, LinkHalf<B, E, Block, RA>), ClientError>
 	where
-	B: Backend<Block, Blake2Hasher> + 'static,
-	E: CallExecutor<Block, Blake2Hasher> + 'static,
-	Api: GrandpaApi<Block>,
-	RA: Send + Sync,
+		B: Backend<Block, Blake2Hasher> + 'static,
+		E: CallExecutor<Block, Blake2Hasher> + 'static + Clone + Send + Sync,
+		RA: GrandpaApi<Block>,
 {
 	use runtime_primitives::traits::Zero;
 	let authority_set = match client.backend().get_aux(AUTHORITY_SET_KEY)? {
@@ -856,7 +853,7 @@ pub fn block_import<B, E, Block: BlockT<Hash=H256>, Api, RA>(client: Arc<Client<
 			// no authority set on disk: fetch authorities from genesis state.
 			// if genesis state is not available, we may be a light client, but these
 			// are unsupported for following GRANDPA directly.
-			let genesis_authorities = api_client
+			let genesis_authorities = client.runtime_api()
 				.grandpa_authorities(&BlockId::number(Zero::zero()))?;
 
 			let authority_set = SharedAuthoritySet::genesis(genesis_authorities);
@@ -873,7 +870,7 @@ pub fn block_import<B, E, Block: BlockT<Hash=H256>, Api, RA>(client: Arc<Client<
 	};
 
 	Ok((
-		GrandpaBlockImport { inner: client.clone(), authority_set: authority_set.clone(), api_client },
+		GrandpaBlockImport { inner: client.clone(), authority_set: authority_set.clone() },
 		LinkHalf { client, authority_set },
 	))
 }
diff --git a/substrate/core/test-runtime/wasm/target/wasm32-unknown-unknown/release/substrate_test_runtime.compact.wasm b/substrate/core/test-runtime/wasm/target/wasm32-unknown-unknown/release/substrate_test_runtime.compact.wasm
index 76ec888e14..75fc636a14 100644
Binary files a/substrate/core/test-runtime/wasm/target/wasm32-unknown-unknown/release/substrate_test_runtime.compact.wasm and b/substrate/core/test-runtime/wasm/target/wasm32-unknown-unknown/release/substrate_test_runtime.compact.wasm differ
diff --git a/substrate/node/runtime/Cargo.toml b/substrate/node/runtime/Cargo.toml
index 1f6ccad0c3..5865927893 100644
--- a/substrate/node/runtime/Cargo.toml
+++ b/substrate/node/runtime/Cargo.toml
@@ -14,7 +14,8 @@ parity-codec-derive = "2.1"
 sr-std = { path = "../../core/sr-std" }
 srml-support = { path = "../../srml/support" }
 substrate-primitives = { path = "../../core/primitives" }
-substrate-client = { path = "../../core/client", optional = true }
+substrate-fg-primitives = { path = "../../core/finality-grandpa/primitives" }
+substrate-client = { path = "../../core/client" }
 substrate-keyring = { path = "../../core/keyring" }
 srml-balances = { path = "../../srml/balances" }
 srml-consensus = { path = "../../srml/consensus" }
@@ -57,5 +58,6 @@ std = [
 	"serde_derive",
 	"serde/std",
 	"safe-mix/std",
-	"substrate-client",
+	"substrate-client/std",
+	"substrate-fg-primitives/std",
 ]
diff --git a/substrate/node/runtime/src/lib.rs b/substrate/node/runtime/src/lib.rs
index 84ffbb4ab0..dca769f4d4 100644
--- a/substrate/node/runtime/src/lib.rs
+++ b/substrate/node/runtime/src/lib.rs
@@ -56,6 +56,7 @@ extern crate srml_upgrade_key as upgrade_key;
 #[macro_use]
 extern crate sr_version as version;
 extern crate node_primitives;
+extern crate substrate_fg_primitives;
 
 #[cfg(feature = "std")]
 use codec::{Encode, Decode};
@@ -72,7 +73,7 @@ use client::runtime_api::ApiExt;
 use runtime_primitives::ApplyResult;
 use runtime_primitives::transaction_validity::TransactionValidity;
 use runtime_primitives::generic;
-use runtime_primitives::traits::{Convert, BlakeTwo256, Block as BlockT};
+use runtime_primitives::traits::{Convert, BlakeTwo256, Block as BlockT, DigestFor, NumberFor};
 #[cfg(feature = "std")]
 use runtime_primitives::traits::ApiRef;
 #[cfg(feature = "std")]
@@ -84,6 +85,7 @@ use council::seats as council_seats;
 #[cfg(any(feature = "std", test))]
 use version::NativeVersion;
 use substrate_primitives::OpaqueMetadata;
+use substrate_fg_primitives::{runtime::GrandpaApi, ScheduledChange};
 
 #[cfg(any(feature = "std", test))]
 pub use runtime_primitives::BuildStorage;
@@ -395,6 +397,19 @@ impl client::runtime_api::Metadata<GBlock> for ClientWithApi {
 	}
 }
 
+#[cfg(feature = "std")]
+impl substrate_fg_primitives::GrandpaApi<GBlock> for ClientWithApi {
+	fn grandpa_pending_change(&self, at: &GBlockId, digest: &DigestFor<GBlock>)
+		-> Result<Option<ScheduledChange<NumberFor<GBlock>>>, client::error::Error> {
+		self.call_api_at(at, "grandpa_pending_change", digest)
+	}
+
+	fn grandpa_authorities(&self, at: &GBlockId)
+		-> Result<Vec<(AuthorityId, u64)>, client::error::Error> {
+		self.call_api_at(at, "grandpa_authorities", &())
+	}
+}
+
 impl_runtime_apis! {
 	impl Core<Block> for Runtime {
 		fn version() -> RuntimeVersion {
@@ -447,4 +462,16 @@ impl_runtime_apis! {
 			Executive::validate_transaction(tx)
 		}
 	}
+
+
+	impl GrandpaApi<Block> for ClientWithApi {
+		fn grandpa_pending_change(digest: DigestFor<Block>)
+			-> Option<ScheduledChange<NumberFor<Block>>> {
+			unimplemented!("Robert, where is the impl?")
+		}
+
+		fn grandpa_authorities() -> Vec<(SessionKey, u64)> {
+			unimplemented!("Robert, where is the impl?")
+		}
+	}
 }
diff --git a/substrate/node/runtime/wasm/Cargo.lock b/substrate/node/runtime/wasm/Cargo.lock
index bb067bc400..4eeae1fd9d 100644
--- a/substrate/node/runtime/wasm/Cargo.lock
+++ b/substrate/node/runtime/wasm/Cargo.lock
@@ -526,6 +526,7 @@ dependencies = [
  "srml-treasury 0.1.0",
  "srml-upgrade-key 0.1.0",
  "substrate-client 0.1.0",
+ "substrate-fg-primitives 0.1.0",
  "substrate-primitives 0.1.0",
 ]
 
@@ -1272,6 +1273,18 @@ dependencies = [
  "wasmi 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "substrate-fg-primitives"
+version = "0.1.0"
+dependencies = [
+ "parity-codec 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parity-codec-derive 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sr-primitives 0.1.0",
+ "sr-std 0.1.0",
+ "substrate-client 0.1.0",
+ "substrate-primitives 0.1.0",
+]
+
 [[package]]
 name = "substrate-keyring"
 version = "0.1.0"
diff --git a/substrate/node/runtime/wasm/Cargo.toml b/substrate/node/runtime/wasm/Cargo.toml
index 9e74ff9d5d..6e9cfd0910 100644
--- a/substrate/node/runtime/wasm/Cargo.toml
+++ b/substrate/node/runtime/wasm/Cargo.toml
@@ -12,6 +12,7 @@ safe-mix = { version = "1.0", default-features = false }
 parity-codec-derive = { version = "2.1" }
 parity-codec = { version = "2.1", default-features = false }
 substrate-primitives = { path = "../../../core/primitives", default-features = false }
+substrate-fg-primitives = { path = "../../../core/finality-grandpa/primitives", default-features = false }
 substrate-client = { path = "../../../core/client", default-features = false }
 sr-std = { path = "../../../core/sr-std", default-features = false }
 srml-support = { path = "../../../srml/support", default-features = false }
@@ -38,6 +39,7 @@ std = [
 	"parity-codec/std",
 	"substrate-primitives/std",
 	"substrate-client/std",
+	"substrate-fg-primitives/std",
 	"sr-std/std",
 	"srml-support/std",
 	"srml-balances/std",
diff --git a/substrate/node/runtime/wasm/target/wasm32-unknown-unknown/release/node_runtime.compact.wasm b/substrate/node/runtime/wasm/target/wasm32-unknown-unknown/release/node_runtime.compact.wasm
index 766de4bda3..8a89da66f1 100644
Binary files a/substrate/node/runtime/wasm/target/wasm32-unknown-unknown/release/node_runtime.compact.wasm and b/substrate/node/runtime/wasm/target/wasm32-unknown-unknown/release/node_runtime.compact.wasm differ