diff --git a/js/src/api/api.js b/js/src/api/api.js
index 9a208ade9..220c3be29 100644
--- a/js/src/api/api.js
+++ b/js/src/api/api.js
@@ -21,6 +21,7 @@ import Contract from './contract';
 
 import { Db, Eth, Parity, Net, Personal, Shh, Signer, Trace, Web3 } from './rpc';
 import Subscriptions from './subscriptions';
+import Pubsub from './pubsub';
 import util from './util';
 import { isFunction } from './util/types';
 
@@ -46,10 +47,13 @@ export default class Api extends EventEmitter {
     this._trace = new Trace(transport);
     this._web3 = new Web3(transport);
 
+    if (isFunction(transport.subscribe)) {
+      this._pubsub = new Pubsub(transport);
+    }
+
     if (allowSubscriptions) {
       this._subscriptions = new Subscriptions(this);
     }
-
     // Doing a request here in test env would cause an error
     if (LocalAccountsMiddleware && process.env.NODE_ENV !== 'test') {
       const middleware = this.parity
@@ -67,6 +71,13 @@ export default class Api extends EventEmitter {
     }
   }
 
+  get pubsub () {
+    if (!this._pubsub) {
+      throw Error('Pubsub is only available with a subscribing-supported transport injected!');
+    }
+    return this._pubsub;
+  }
+
   get db () {
     return this._db;
   }
diff --git a/js/src/api/pubsub/eth/eth.js b/js/src/api/pubsub/eth/eth.js
new file mode 100644
index 000000000..0bbc85bec
--- /dev/null
+++ b/js/src/api/pubsub/eth/eth.js
@@ -0,0 +1,227 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+import PubsubBase from '../pubsubBase';
+
+import { inAddress, inBlockNumber, inHex, inNumber16, inOptions, inFilter } from '../../format/input';
+import { outAddress, outBlock, outNumber, outTransaction, outSyncing, outReceipt, outLog } from '../../format/output';
+
+export default class Eth extends PubsubBase {
+  constructor (transport) {
+    super(transport);
+    this._api = 'parity';
+  }
+
+  newHeads (callback) {
+    return this.addListener('eth', 'newHeads', callback);
+  }
+
+  logs (callback) {
+    throw Error('not supported yet');
+  }
+
+  //  eth API
+  protocolVersion (callback) {
+    return this.addListener(this._api, 'eth_protocolVersion', callback);
+  }
+
+  syncing (callback) {
+    return this.addListener(this._api, 'eth_syncing', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outSyncing(data));
+    });
+  }
+
+  hashrate (callback) {
+    return this.addListener(this._api, 'eth_hashrate', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  coinbase (callback) {
+    return this.addListener(this._api, 'eth_coinbase', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddress(data));
+    });
+  }
+
+  mining (callback) {
+    return this.addListener(this._api, 'eth_mining', callback);
+  }
+
+  gasPrice (callback) {
+    return this.addListener(this._api, 'eth_gasPrice', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  accounts (callback) {
+    return this.addListener(this._api, 'eth_accounts', (error, accounts) => {
+      error
+        ? callback(error)
+        : callback(null, (accounts || []).map(outAddress));
+    });
+  }
+
+  blockNumber (callback) {
+    return this.addListener(this._api, 'eth_blockNumber', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  getBalance (callback, address, blockNumber = 'latest') {
+    return this.addListener(this._api, 'eth_getBalance', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    }, [inAddress(address), inBlockNumber(blockNumber)]);
+  }
+
+  getStorageAt (callback, address, index = 0, blockNumber = 'latest') {
+    return this.addListener(this._api, 'eth_getStorageAt', callback, [inAddress(address), inNumber16(index), inBlockNumber(blockNumber)]);
+  }
+
+  getBlockByHash (callback, hash, full = false) {
+    return this.addListener(this._api, 'eth_getBlockByHash', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outBlock(data));
+    }, [inHex(hash), full]);
+  }
+
+  getBlockByNumber (callback, blockNumber = 'latest', full = false) {
+    return this.addListener(this._api, 'eth_getBlockByNumber', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outBlock(data));
+    }, [inBlockNumber(blockNumber), full]);
+  }
+
+  getTransactionCount (callback, address, blockNumber = 'latest') {
+    return this.addListener(this._api, 'eth_getTransactionCount', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    }, [inAddress(address), inBlockNumber(blockNumber)]);
+  }
+
+  getBlockTransactionCountByHash (callback, hash) {
+    return this.addListener(this._api, 'eth_getBlockTransactionCountByHash', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    }, [inHex(hash)]);
+  }
+
+  getBlockTransactionCountByNumber (callback, blockNumber = 'latest') {
+    return this.addListener(this._api, 'eth_getBlockTransactionCountByNumber', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    }, [inBlockNumber(blockNumber)]);
+  }
+
+  getUncleCountByBlockHash (callback, hash) {
+    return this.addListener(this._api, 'eth_getUncleCountByBlockHash', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    }, [inHex(hash)]);
+  }
+
+  getUncleCountByBlockNumber (callback, blockNumber = 'latest') {
+    return this.addListener(this._api, 'eth_getUncleCountByBlockNumber', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    }, [inBlockNumber(blockNumber)]);
+  }
+
+  getCode (callback, address, blockNumber = 'latest') {
+    return this.addListener(this._api, 'eth_getCode', callback, [inAddress(address), inBlockNumber(blockNumber)]);
+  }
+
+  call (callback, options, blockNumber = 'latest') {
+    return this.addListener(this._api, 'eth_call', callback, [inOptions(options), inBlockNumber(blockNumber)]);
+  }
+
+  estimateGas (callback, options) {
+    return this.addListener(this._api, 'eth_estimateGas', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    }, [inOptions(options)]);
+  }
+
+  getTransactionByHash (callback, hash) {
+    return this.addListener(this._api, 'eth_getTransactionByHash', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outTransaction(data));
+    }, [inHex(hash)]);
+  }
+
+  getTransactionByBlockHashAndIndex (callback, hash, index = 0) {
+    return this.addListener(this._api, 'eth_getTransactionByBlockHashAndIndex', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outTransaction(data));
+    }, [inHex(hash), inNumber16(index)]);
+  }
+
+  getTransactionByBlockNumberAndIndex (callback, blockNumber = 'latest', index = 0) {
+    return this.addListener(this._api, 'eth_getTransactionByBlockNumberAndIndex', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outTransaction(data));
+    }, [inBlockNumber(blockNumber), inNumber16(index)]);
+  }
+
+  getTransactionReceipt (callback, txhash) {
+    return this.addListener(this._api, 'eth_getTransactionReceipt', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outReceipt(data));
+    }, [inHex(txhash)]);
+  }
+
+  getUncleByBlockHashAndIndex (callback, hash, index = 0) {
+    return this.addListener(this._api, 'eth_getUncleByBlockHashAndIndex', callback, [inHex(hash), inNumber16(index)]);
+  }
+
+  getUncleByBlockNumberAndIndex (callback, blockNumber = 'latest', index = 0) {
+    return this.addListener(this._api, 'eth_getUncleByBlockNumberAndIndex', callback, [inBlockNumber(blockNumber), inNumber16(index)]);
+  }
+
+  getLogs (callback, options) {
+    return this.addListener(this._api, 'eth_getLogs', (error, logs) => {
+      error
+        ? callback(error)
+        : callback(null, (logs) => logs.map(outLog));
+    }, [inFilter(options)]);
+  }
+
+  getWork (callback) {
+    return this.addListener(this._api, 'eth_getWork', callback);
+  }
+}
diff --git a/js/src/api/pubsub/eth/index.js b/js/src/api/pubsub/eth/index.js
new file mode 100644
index 000000000..3b8d1994c
--- /dev/null
+++ b/js/src/api/pubsub/eth/index.js
@@ -0,0 +1,16 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+export default from './eth';
diff --git a/js/src/api/pubsub/index.js b/js/src/api/pubsub/index.js
new file mode 100644
index 000000000..bf342e1de
--- /dev/null
+++ b/js/src/api/pubsub/index.js
@@ -0,0 +1,16 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+export default from './pubsub';
diff --git a/js/src/api/pubsub/net/index.js b/js/src/api/pubsub/net/index.js
new file mode 100644
index 000000000..6d13847c5
--- /dev/null
+++ b/js/src/api/pubsub/net/index.js
@@ -0,0 +1,16 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+export default from './net';
diff --git a/js/src/api/pubsub/net/net.js b/js/src/api/pubsub/net/net.js
new file mode 100644
index 000000000..e1dc3c4e1
--- /dev/null
+++ b/js/src/api/pubsub/net/net.js
@@ -0,0 +1,42 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+import PubsubBase from '../pubsubBase';
+
+import { outNumber } from '../../format/output';
+
+export default class Net extends PubsubBase {
+  constructor (transport) {
+    super(transport);
+    this._api = 'parity';
+  }
+
+  // net API
+  version (callback) {
+    return this.addListener(this._api, 'net_version', callback);
+  }
+
+  peerCount (callback) {
+    return this.addListener(this._api, 'net_peerCount', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  listening (callback) {
+    return this.addListener(this._api, 'net_listening', callback);
+  }
+}
diff --git a/js/src/api/pubsub/parity/index.js b/js/src/api/pubsub/parity/index.js
new file mode 100644
index 000000000..33ce7aa7f
--- /dev/null
+++ b/js/src/api/pubsub/parity/index.js
@@ -0,0 +1,16 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+export default from './parity';
diff --git a/js/src/api/pubsub/parity/parity.js b/js/src/api/pubsub/parity/parity.js
new file mode 100644
index 000000000..bf18effa1
--- /dev/null
+++ b/js/src/api/pubsub/parity/parity.js
@@ -0,0 +1,355 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import PubsubBase from '../pubsubBase';
+import { inAddress, inBlockNumber, inData, inHex, inDeriveHash, inDeriveIndex } from '../../format/input';
+import { outAccountInfo, outAddress, outBlock, outChainStatus, outHistogram, outHwAccountInfo, outNodeKind, outNumber, outPeers, outTransaction, outAddresses, outRecentDapps, outVaultMeta } from '../../format/output';
+
+export default class Parity extends PubsubBase {
+  constructor (transport) {
+    super(transport);
+    this._api = 'parity';
+  }
+
+  // parity API
+  accountsInfo (callback) {
+    return this.addListener(this._api, 'parity_accountsInfo', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAccountInfo(data));
+    });
+  }
+
+  hardwareAccountsInfo (callback) {
+    return this.addListener(this._api, 'parity_hardwareAccountsInfo', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outHwAccountInfo(data));
+    });
+  }
+
+  defaultAccount (callback) {
+    return this.addListener(this._api, 'parity_defaultAccount', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddress(data));
+    });
+  }
+
+  transactionsLimit (callback) {
+    return this.addListener(this._api, 'parity_transactionsLimit', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  extraData (callback) {
+    return this.addListener(this._api, 'parity_extraData', callback);
+  }
+
+  gasFloorTarget (callback) {
+    return this.addListener(this._api, 'parity_gasFloorTarget', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  gasCeilTarget (callback) {
+    return this.addListener(this._api, 'parity_gasCeilTarget', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  minGasPrice (callback) {
+    return this.addListener(this._api, 'parity_minGasPrice', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  devLogs (callback) {
+    return this.addListener(this._api, 'parity_devLogs', callback);
+  }
+
+  devLogsLevels (callback) {
+    return this.addListener(this._api, 'parity_devLogsLevels', callback);
+  }
+
+  netChain (callback) {
+    return this.addListener(this._api, 'parity_netChain', callback);
+  }
+
+  netPeers (callback) {
+    return this.addListener(this._api, 'parity_netPeers', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outPeers(data));
+    });
+  }
+
+  netPort (callback) {
+    return this.addListener(this._api, 'parity_netPort', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  rpcSettings (callback) {
+    return this.addListener(this._api, 'parity_rpcSettings', callback);
+  }
+
+  nodeName (callback) {
+    return this.addListener(this._api, 'parity_nodeName', callback);
+  }
+
+  defaultExtraData (callback) {
+    return this.addListener(this._api, 'parity_defaultExtraData', callback);
+  }
+
+  gasPriceHistogram (callback) {
+    return this.addListener(this._api, 'parity_gasPriceHistogram', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outHistogram(data));
+    });
+  }
+
+  unsignedTransactionsCount (callback) {
+    return this.addListener(this._api, 'parity_unsignedTransactionsCount', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    });
+  }
+
+  registryAddress (callback) {
+    return this.addListener(this._api, 'parity_registryAddress', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddress(data));
+    });
+  }
+
+  listAccounts (callback, count, offset = null, blockNumber = 'latest') {
+    return this.addListener(this._api, 'parity_listAccounts', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, (data) => (data || []).map(outAddress));
+    }, [count, inAddress(offset), inBlockNumber(blockNumber)]);
+  }
+
+  listStorageKeys (callback, address, count, hash = null, blockNumber = 'latest') {
+    return this.addListener(this._api, 'parity_listStorageKeys', callback, [inAddress(address), count, inHex(hash), inBlockNumber(blockNumber)]);
+  }
+
+  pendingTransactions (callback) {
+    return this.addListener(this._api, 'parity_pendingTransactions', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outTransaction(data));
+    });
+  }
+
+  futureTransactions (callback) {
+    return this.addListener(this._api, 'parity_futureTransactions', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outTransaction(data));
+    });
+  }
+
+  pendingTransactionsStats (callback) {
+    return this.addListener(this._api, 'parity_pendingTransactionsStats', callback);
+  }
+
+  localTransactions (callback) {
+    return this.addListener(this._api, 'parity_localTransactions', (error, transactions) => {
+      error
+        ? callback(error)
+        : callback(null, transactions => {
+          Object.values(transactions)
+            .filter(tx => tx.transaction)
+            .map(tx => {
+              tx.transaction = outTransaction(tx.transaction);
+            });
+          return transactions;
+        });
+    });
+  }
+
+  dappsUrl (callback) {
+    return this.addListener(this._api, 'parity_dappsUrl', callback);
+  }
+
+  wsUrl (callback) {
+    return this.addListener(this._api, 'parity_wsUrl', callback);
+  }
+
+  nextNonce (callback, account) {
+    return this.addListener(this._api, 'parity_nextNonce', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNumber(data));
+    }, [inAddress(account)]);
+  }
+
+  mode (callback) {
+    return this.addListener(this._api, 'parity_mode', callback);
+  }
+
+  chain (callback) {
+    return this.addListener(this._api, 'parity_chain', callback);
+  }
+
+  enode (callback) {
+    return this.addListener(this._api, 'parity_enode', callback);
+  }
+
+  consensusCapability (callback) {
+    return this.addListener(this._api, 'parity_consensusCapability', callback);
+  }
+
+  versionInfo (callback) {
+    return this.addListener(this._api, 'parity_versionInfo', callback);
+  }
+
+  releasesInfo (callback) {
+    return this.addListener(this._api, 'parity_releasesInfo', callback);
+  }
+
+  chainStatus (callback) {
+    return this.addListener(this._api, 'parity_chainStatus', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outChainStatus(data));
+    });
+  }
+
+  nodeKind (callback) {
+    return this.addListener(this._api, 'parity_nodeKind', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outNodeKind(data));
+    });
+  }
+
+  getBlockHeaderByNumber (callback, blockNumber = 'latest') {
+    return this.addListener(this._api, 'parity_getBlockHeaderByNumber', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outBlock(data));
+    }, [inBlockNumber(blockNumber)]);
+  }
+
+  cidV0 (callback, data) {
+    return this.addListener(this._api, 'parity_cidV0', callback, [inData(data)]);
+  }
+
+  // parity accounts API (only secure API or configured to be exposed)
+  allAccountsInfo (callback) {
+    return this._addListener(this._api, 'parity_allAccountsInfo', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAccountInfo(data));
+    });
+  }
+
+  getDappAddresses (callback, dappId) {
+    return this._addListener(this._api, 'parity_getDappAddresses', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddresses(data));
+    }, [dappId]);
+  }
+
+  getDappDefaultAddress (callback, dappId) {
+    return this._addListener(this._api, 'parity_getDappDefaultAddress', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddress(data));
+    }, [dappId]);
+  }
+
+  getNewDappsAddresses (callback) {
+    return this._addListener(this._api, 'parity_getDappDefaultAddress', (error, addresses) => {
+      error
+        ? callback(error)
+        : callback(null, addresses ? addresses.map(outAddress) : null);
+    });
+  }
+
+  getNewDappsDefaultAddress (callback) {
+    return this._addListener(this._api, 'parity_getNewDappsDefaultAddress', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddress(data));
+    });
+  }
+
+  listRecentDapps (callback) {
+    return this._addListener(this._api, 'parity_listRecentDapps', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outRecentDapps(data));
+    });
+  }
+
+  listGethAccounts (callback) {
+    return this._addListener(this._api, 'parity_listGethAccounts', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddresses(data));
+    });
+  }
+
+  listVaults (callback) {
+    return this._addListener(this._api, 'parity_listVaults', callback);
+  }
+
+  listOpenedVaults (callback) {
+    return this._addListener(this._api, 'parity_listOpenedVaults', callback);
+  }
+
+  getVaultMeta (callback, vaultName) {
+    return this._addListener(this._api, 'parity_getVaultMeta', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outVaultMeta(data));
+    }, [vaultName]);
+  }
+
+  deriveAddressHash (callback, address, password, hash, shouldSave) {
+    return this._addListener(this._api, 'parity_deriveAddressHash', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddress(data));
+    }, [inAddress(address), password, inDeriveHash(hash), !!shouldSave]);
+  }
+
+  deriveAddressIndex (callback, address, password, index, shouldSave) {
+    return this._addListener(this._api, 'parity_deriveAddressIndex', (error, data) => {
+      error
+        ? callback(error)
+        : callback(null, outAddress(data));
+    }, [inAddress(address), password, inDeriveIndex(index), !!shouldSave]);
+  }
+}
diff --git a/js/src/api/pubsub/pubsub.js b/js/src/api/pubsub/pubsub.js
new file mode 100644
index 000000000..edbc201ae
--- /dev/null
+++ b/js/src/api/pubsub/pubsub.js
@@ -0,0 +1,50 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import Eth from './eth';
+import Parity from './parity';
+import Net from './net';
+
+import { isFunction } from '../util/types';
+
+export default class Pubsub {
+  constructor (transport) {
+    if (!transport || !isFunction(transport.subscribe)) {
+      throw new Error('Pubsub API needs transport with subscribe() function defined. (WebSocket)');
+    }
+
+    this._eth = new Eth(transport);
+    this._net = new Net(transport);
+    this._parity = new Parity(transport);
+  }
+
+  get net () {
+    return this._net;
+  }
+
+  get eth () {
+    return this._eth;
+  }
+
+  get parity () {
+    return this._parity;
+  }
+
+  unsubscribe (subscriptionIds) {
+    // subscriptions are namespace independent. Thus we can simply removeListener from any.
+    return this._parity.removeListener(subscriptionIds);
+  }
+}
diff --git a/js/src/api/pubsub/pubsub.spec.js b/js/src/api/pubsub/pubsub.spec.js
new file mode 100644
index 000000000..10fcd2edb
--- /dev/null
+++ b/js/src/api/pubsub/pubsub.spec.js
@@ -0,0 +1,613 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import BigNumber from 'bignumber.js';
+import { TEST_WS_URL, mockWs } from '../../../test/mockRpc';
+import { isBigNumber } from '../../../test/types';
+
+import Ws from '../transport/ws';
+import Pubsub from './pubsub';
+
+describe('api/pubsub/Pubsub', () => {
+  let scope;
+  let instance;
+  const address = '0x63Cf90D3f0410092FC0fca41846f596223979195';
+
+  describe('accountsInfo', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: {
+            '0x63cf90d3f0410092fc0fca41846f596223979195': {
+              name: 'name', uuid: 'uuid', meta: '{"data":"data"}'
+            }
+          },
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('retrieves the available account info', (done) => {
+      instance.parity.accountsInfo((error, result) => {
+        expect(error).to.be.null;
+        expect(result).to.deep.equal({
+          '0x63Cf90D3f0410092FC0fca41846f596223979195': {
+            name: 'name', uuid: 'uuid', meta: {
+              data: 'data'
+            }
+          }
+        });
+        done();
+      });
+    });
+  });
+
+  describe('Unsubscribe', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2 },
+                      { method: 'parity_unsubscribe', reply: true }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('Promise gets resolved on success.', (done) => {
+      instance.parity.accountsInfo().then(s => {
+        instance.parity.unsubscribe(s).then(b => {
+          expect(b).to.be.true;
+        });
+      });
+      done();
+    });
+  });
+
+  describe('chainStatus', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: {
+            'blockGap': [0x123, 0x456]
+          },
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('retrieves the chain status', (done) => {
+      instance.parity.chainStatus((error, result) => {
+        expect(error).to.be.null;
+        expect(result).to.deep.equal({
+          'blockGap': [new BigNumber(0x123), new BigNumber(0x456)]
+        });
+        done();
+      });
+    });
+  });
+
+  describe('gasFloorTarget', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: '0x123456',
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns the gasfloor, formatted', (done) => {
+      instance.parity.gasFloorTarget((error, result) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(result)).to.be.true;
+        expect(result.eq(0x123456)).to.be.true;
+        done();
+      });
+    });
+  });
+
+  describe('transactionsLimit', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: 1024,
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns the tx limit, formatted', (done) => {
+      instance.parity.transactionsLimit((error, result) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(result)).to.be.true;
+        expect(result.eq(1024)).to.be.true;
+        done();
+      });
+    });
+  });
+
+  describe('minGasPrice', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: '0x123456',
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns the min gasprice, formatted', (done) => {
+      instance.parity.minGasPrice((error, result) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(result)).to.be.true;
+        expect(result.eq(0x123456)).to.be.true;
+        done();
+      });
+    });
+  });
+
+  describe('netPeers', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: { active: 123, connected: 456, max: 789, peers: [] },
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns the peer structure, formatted', (done) => {
+      instance.parity.netPeers((error, peers) => {
+        expect(error).to.be.null;
+        expect(peers.active.eq(123)).to.be.true;
+        expect(peers.connected.eq(456)).to.be.true;
+        expect(peers.max.eq(789)).to.be.true;
+        done();
+      });
+    });
+  });
+
+  describe('netPort', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: 33030,
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns the connected port, formatted', (done) => {
+      instance.parity.netPort((error, count) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(count)).to.be.true;
+        expect(count.eq(33030)).to.be.true;
+        done();
+      });
+    });
+  });
+
+// Eth API
+  describe('accounts', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: [address.toLowerCase()],
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns a list of accounts, formatted', (done) => {
+      instance.eth.accounts((error, accounts) => {
+        expect(error).to.be.null;
+        expect(accounts).to.deep.equal([address]);
+        done();
+      });
+    });
+  });
+
+  describe('newHeads', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'eth_subscribe', reply: 2, subscription: {
+        method: 'eth_subscription',
+        params: {
+          result: '0x123456',
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns newHeads for eth_subscribe', (done) => {
+      instance.eth.newHeads((error, blockNumber) => {
+        expect(error).to.be.null;
+        expect(blockNumber).to.equal('0x123456');
+        done();
+      });
+    });
+  });
+
+  describe('blockNumber', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: '0x123456',
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns the current blockNumber, formatted', (done) => {
+      instance.eth.blockNumber((error, blockNumber) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(blockNumber)).to.be.true;
+        expect(blockNumber.toString(16)).to.equal('123456');
+        done();
+      });
+    });
+  });
+
+  describe('call', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: [],
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('formats the input options & blockNumber', (done) => {
+      instance.eth.call((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_call', [{ data: '0x12345678' }, 'earliest']]);
+        done();
+      }, { data: '12345678' }, 'earliest');
+    });
+
+    it('provides a latest blockNumber when not specified', (done) => {
+      instance.eth.call((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_call', [{ data: '0x12345678' }, 'latest']]);
+        done();
+      }, { data: '12345678' });
+    });
+  });
+
+  describe('coinbase', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: address.toLowerCase(),
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns the coinbase, formatted', (done) => {
+      instance.eth.coinbase((error, account) => {
+        expect(error).to.be.null;
+        expect(account).to.deep.equal(address);
+        done();
+      });
+    });
+  });
+
+  describe('estimateGas', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: '0x123',
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('converts the options correctly', (done) => {
+      instance.eth.estimateGas((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_estimateGas', [{ gas: '0x5208' }]]);
+        done();
+      }, { gas: 21000 });
+    });
+
+    it('returns the gas used, formatted', (done) => {
+      instance.eth.estimateGas((error, gas) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(gas)).to.be.true;
+        expect(gas.toString(16)).to.deep.equal('123');
+        done();
+      });
+    });
+  });
+
+  describe('gasPrice', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: '0x123',
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('returns the gas price, formatted', (done) => {
+      instance.eth.gasPrice((error, price) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(price)).to.be.true;
+        expect(price.toString(16)).to.deep.equal('123');
+        done();
+      });
+    });
+  });
+
+  describe('getBalance', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: '0x123',
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('passes in the address (default blockNumber)', (done) => {
+      instance.eth.getBalance((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getBalance', [address.toLowerCase(), 'latest']]);
+        done();
+      }, address);
+    });
+
+    it('passes in the address & blockNumber', (done) => {
+      instance.eth.getBalance((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getBalance', [address.toLowerCase(), '0x456']]);
+        done();
+      }, address, 0x456);
+    });
+
+    it('returns the balance', (done) => {
+      instance.eth.getBalance((error, balance) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(balance)).to.be.true;
+        expect(balance.toString(16)).to.deep.equal('123');
+        done();
+      }, address);
+    });
+  });
+
+  describe('getBlockByHash', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: { miner: address.toLowerCase() },
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('formats the input hash as a hash, default full', (done) => {
+      instance.eth.getBlockByHash((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getBlockByHash', ['0x1234', false]]);
+        done();
+      }, '1234');
+    });
+
+    it('formats the input hash as a hash, full true', (done) => {
+      instance.eth.getBlockByHash((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getBlockByHash', ['0x1234', true]]);
+        done();
+      }, '1234', true);
+    });
+
+    it('formats the output into block', (done) => {
+      instance.eth.getBlockByHash((error, block) => {
+        expect(error).to.be.null;
+        expect(block.miner).to.equal(address);
+        done();
+      }, '1234');
+    });
+  });
+
+  describe('getBlockByNumber', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: { miner: address.toLowerCase() },
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('assumes blockNumber latest & full false', (done) => {
+      instance.eth.getBlockByNumber((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getBlockByNumber', ['latest', false]]);
+        done();
+      });
+    });
+
+    it('uses input blockNumber & full false', (done) => {
+      instance.eth.getBlockByNumber((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getBlockByNumber', ['0x1234', false]]);
+        done();
+      }, '0x1234');
+    });
+
+    it('formats the input blockNumber, full true', (done) => {
+      instance.eth.getBlockByNumber((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getBlockByNumber', ['0x1234', true]]);
+        done();
+      }, 0x1234, true);
+    });
+
+    it('formats the output into block', (done) => {
+      instance.eth.getBlockByNumber((error, block) => {
+        expect(error).to.be.null;
+        expect(block.miner).to.equal(address);
+        done();
+      }, 0x1234);
+    });
+  });
+
+  describe('getTransactionCount', () => {
+    beforeEach(() => {
+      scope = mockWs([{ method: 'parity_subscribe', reply: 2, subscription: {
+        method: 'parity_subscription',
+        params: {
+          result: '0x123',
+          subscription: 2
+        }
+      } }]);
+      instance = new Pubsub(new Ws(TEST_WS_URL));
+    });
+
+    afterEach(() => {
+      scope.stop();
+    });
+
+    it('passes in the address (default blockNumber)', (done) => {
+      instance.eth.getTransactionCount((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getTransactionCount', [address.toLowerCase(), 'latest']]);
+        done();
+      }, address);
+    });
+
+    it('passes in the address & blockNumber', (done) => {
+      instance.eth.getTransactionCount((error) => {
+        expect(error).to.be.null;
+        expect(scope.body.parity_subscribe.params).to.deep.equal(['eth_getTransactionCount', [address.toLowerCase(), '0x456']]);
+        done();
+      }, address, 0x456);
+    });
+
+    it('returns the count, formatted', (done) => {
+      instance.eth.getTransactionCount((error, count) => {
+        expect(error).to.be.null;
+        expect(isBigNumber(count)).to.be.true;
+        expect(count.toString(16)).to.equal('123');
+        done();
+      }, address, 0x456);
+    });
+  });
+});
diff --git a/js/src/api/pubsub/pubsubBase.js b/js/src/api/pubsub/pubsubBase.js
new file mode 100644
index 000000000..fcc7525d5
--- /dev/null
+++ b/js/src/api/pubsub/pubsubBase.js
@@ -0,0 +1,37 @@
+// Copyright 2015-2017 Parity Technologies (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default class PubsubBase {
+  // Provider for websocket pubsub transport
+  constructor (transport) {
+    this._transport = transport;
+  }
+
+  addListener (module, eventName, callback, eventParams) {
+    return eventParams
+     ? this._transport.subscribe(module, callback, eventName, eventParams)
+     : this._transport.subscribe(module, callback, eventName, []);
+    // this._transport.subscribe(module, callback, eventName);  After Patch from tomac is merged to master! =>  eth_subscribe does not support empty array as params
+  }
+
+  removeListener (subscriptionIds) {
+    return this._transport.unsubscribe(subscriptionIds);
+  }
+
+  unsubscribe (subscriptionIds) {
+    return this.removeListener(subscriptionIds);
+  }
+}
diff --git a/js/src/api/rpc/parity/parity.spec.js b/js/src/api/rpc/parity/parity.spec.js
index d7eb41047..6ba7a1c83 100644
--- a/js/src/api/rpc/parity/parity.spec.js
+++ b/js/src/api/rpc/parity/parity.spec.js
@@ -110,7 +110,7 @@ describe('api/rpc/parity', () => {
     });
   });
 
-  describe('newPeers', () => {
+  describe('netPeers', () => {
     it('returns the peer structure, formatted', () => {
       mockHttp([{ method: 'parity_netPeers', reply: { result: { active: 123, connected: 456, max: 789, peers: [] } } }]);
 
diff --git a/js/src/api/rpc/trace/trace.js b/js/src/api/rpc/trace/trace.js
index 29494a9ae..26b19b378 100644
--- a/js/src/api/rpc/trace/trace.js
+++ b/js/src/api/rpc/trace/trace.js
@@ -28,9 +28,9 @@ export default class Trace {
       .then(outTraces);
   }
 
-  call (options, blockNumber = 'latest', whatTrace = ['trace']) {
+  call (options, whatTrace = ['trace'], blockNumber = 'latest') {
     return this._transport
-      .execute('trace_call', inOptions(options), inBlockNumber(blockNumber), inTraceType(whatTrace))
+      .execute('trace_call', inOptions(options), inTraceType(whatTrace), inBlockNumber(blockNumber))
       .then(outTraceReplay);
   }
 
diff --git a/js/src/api/transport/ws/ws.js b/js/src/api/transport/ws/ws.js
index 63cfcc5ec..3c642d5f8 100644
--- a/js/src/api/transport/ws/ws.js
+++ b/js/src/api/transport/ws/ws.js
@@ -22,12 +22,14 @@ import TransportError from '../error';
 
 /* global WebSocket */
 export default class Ws extends JsonRpcBase {
-  constructor (url, token, autoconnect = true) {
+  // token is optional (secure API)
+  constructor (url, token = null, autoconnect = true) {
     super();
 
     this._url = url;
     this._token = token;
     this._messages = {};
+    this._subscriptions = { 'eth_subscription': [], 'parity_subscription': [] };
     this._sessionHash = null;
 
     this._connecting = false;
@@ -68,10 +70,6 @@ export default class Ws extends JsonRpcBase {
       this._reconnectTimeoutId = null;
     }
 
-    const time = parseInt(new Date().getTime() / 1000, 10);
-    const sha3 = keccak_256(`${this._token}:${time}`);
-    const hash = `${sha3}_${time}`;
-
     if (this._ws) {
       this._ws.onerror = null;
       this._ws.onopen = null;
@@ -81,13 +79,23 @@ export default class Ws extends JsonRpcBase {
       this._ws = null;
       this._sessionHash = null;
     }
-
     this._connecting = true;
     this._connected = false;
     this._lastError = null;
 
-    this._sessionHash = sha3;
-    this._ws = new WebSocket(this._url, hash);
+    // rpc secure API
+    if (this._token) {
+      const time = parseInt(new Date().getTime() / 1000, 10);
+      const sha3 = keccak_256(`${this._token}:${time}`);
+      const hash = `${sha3}_${time}`;
+
+      this._sessionHash = sha3;
+      this._ws = new WebSocket(this._url, hash);
+    // non-secure API
+    } else {
+      this._ws = new WebSocket(this._url);
+    }
+
     this._ws.onerror = this._onError;
     this._ws.onopen = this._onOpen;
     this._ws.onclose = this._onClose;
@@ -194,13 +202,48 @@ export default class Ws extends JsonRpcBase {
     }, 50);
   }
 
+  _extract = (result) => {
+    const { result: res, id, method, params } = result;
+    const msg = this._messages[id];
+
+    // initial pubsub ACK
+    if (id && msg.subscription) {
+      // save subscription to map subId -> messageId
+      this._subscriptions[msg.subscription][res] = id;
+      // resolve promise with messageId because subId's can collide (eth/parity)
+      msg.resolve(id);
+      // save subId for unsubscribing later
+      msg.subId = res;
+      return msg;
+    }
+
+    // normal message
+    if (id) {
+      return msg;
+    }
+
+    // pubsub format
+    if (method.includes('subscription')) {
+      const messageId = this._messages[this._subscriptions[method][params.subscription]];
+
+      if (messageId) {
+        return messageId;
+      } else {
+        throw Error(`Received Subscription which is already unsubscribed ${JSON.stringify(result)}`);
+      }
+    }
+
+    throw Error(`Unknown message format: No ID or subscription ${JSON.stringify(result)}`);
+  }
+
   _onMessage = (event) => {
     try {
       const result = JSON.parse(event.data);
-      const { method, params, json, resolve, reject } = this._messages[result.id];
+      const { method, params, json, resolve, reject, callback, subscription } = this._extract(result);
 
       Logging.send(method, params, { json, result });
 
+      result.error = (result.params && result.params.error) || result.error;
       if (result.error) {
         this.error(event.data);
 
@@ -211,14 +254,23 @@ export default class Ws extends JsonRpcBase {
 
         const error = new TransportError(method, result.error.code, result.error.message);
 
-        reject(error);
+        if (result.id) {
+          reject(error);
+        } else {
+          callback(error);
+        }
 
         delete this._messages[result.id];
         return;
       }
 
-      resolve(result.result);
-      delete this._messages[result.id];
+      // if not initial subscription message resolve & delete
+      if (result.id && !subscription) {
+        resolve(result.result);
+        delete this._messages[result.id];
+      } else if (result.params) {
+        callback(null, result.params.result);
+      }
     } catch (e) {
       console.error('ws::_onMessage', event.data, e);
     }
@@ -249,6 +301,43 @@ export default class Ws extends JsonRpcBase {
     });
   }
 
+  _methodsFromApi (api) {
+    const method = `${api}_subscribe`;
+    const uMethod = `${api}_unsubscribe`;
+    const subscription = `${api}_subscription`;
+
+    return { method, uMethod, subscription };
+  }
+
+  subscribe (api, callback, ...params) {
+    return new Promise((resolve, reject) => {
+      const id = this.id;
+      const { method, uMethod, subscription } = this._methodsFromApi(api);
+      const json = this.encode(method, params);
+
+      this._messages[id] = { id, method, uMethod, params, json, resolve, reject, callback, subscription };
+
+      this._send(id);
+    });
+  }
+
+  unsubscribe (messageId) {
+    return new Promise((resolve, reject) => {
+      const id = this.id;
+      const { subId, uMethod, subscription } = this._messages[messageId];
+      const params = [subId];
+      const json = this.encode(uMethod, params);
+      const uResolve = (v) => {
+        delete this._messages[messageId];
+        delete this._subscriptions[subscription][subId];
+        resolve(v);
+      };
+
+      this._messages[id] = { id, method: uMethod, params, json, resolve: uResolve, reject };
+      this._send(id);
+    });
+  }
+
   set url (url) {
     this._url = url;
   }
diff --git a/js/src/jsonrpc/interfaces/eth.js b/js/src/jsonrpc/interfaces/eth.js
index c52b9bc7a..d54c57325 100644
--- a/js/src/jsonrpc/interfaces/eth.js
+++ b/js/src/jsonrpc/interfaces/eth.js
@@ -545,6 +545,39 @@ The following options are possible for the \`defaultBlock\` parameter:
         input: {
           type: Data,
           desc: 'the data send along with the transaction.'
+        },
+        v: {
+          type: Quantity,
+          desc: 'the standardised V field of the signature.'
+        },
+        standard_v: {
+          type: Quantity,
+          desc: 'the standardised V field of the signature (0 or 1).'
+        },
+        r: {
+          type: Quantity,
+          desc: 'the R field of the signature.'
+        },
+        raw: {
+          type: Data,
+          desc: 'raw transaction data'
+        },
+        publicKey: {
+          type: Hash,
+          desc: 'public key of the signer.'
+        },
+        networkId: {
+          type: Quantity,
+          desc: 'the network id of the transaction, if any.'
+        },
+        creates: {
+          type: Hash,
+          desc: 'creates contract hash'
+        },
+        condition: {
+          type: Object,
+          optional: true,
+          desc: 'conditional submission, Block number in `block` or timestamp in `time` or `null`. (parity-feature)'
         }
       },
       example: {
@@ -1057,6 +1090,39 @@ The following options are possible for the \`defaultBlock\` parameter:
             input: {
               type: Data,
               desc: 'the data send along with the transaction.'
+            },
+            v: {
+              type: Quantity,
+              desc: 'the standardised V field of the signature.'
+            },
+            standard_v: {
+              type: Quantity,
+              desc: 'the standardised V field of the signature (0 or 1).'
+            },
+            r: {
+              type: Quantity,
+              desc: 'the R field of the signature.'
+            },
+            raw: {
+              type: Data,
+              desc: 'raw transaction data'
+            },
+            publicKey: {
+              type: Hash,
+              desc: 'public key of the signer.'
+            },
+            networkId: {
+              type: Quantity,
+              desc: 'the network id of the transaction, if any.'
+            },
+            creates: {
+              type: Hash,
+              desc: 'creates contract hash'
+            },
+            condition: {
+              type: Object,
+              optional: true,
+              desc: 'conditional submission, Block number in `block` or timestamp in `time` or `null`. (parity-feature)'
             }
           }
         }
diff --git a/js/test/mockRpc.js b/js/test/mockRpc.js
index eb15e98ed..b3c6abc3e 100644
--- a/js/test/mockRpc.js
+++ b/js/test/mockRpc.js
@@ -70,6 +70,10 @@ export function mockWs (requests) {
     scope.requests++;
 
     mockServer.send(JSON.stringify(response));
+
+    if (request.method.match('subscribe') && request.subscription) {
+      mockServer.send(JSON.stringify(request.subscription));
+    }
   });
 
   return scope;