diff --git a/package-lock.json b/package-lock.json
index 31a8dda6dae8..041e61a1b438 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -144,6 +144,15 @@
         }
       }
     },
+    "@polkadot/api-format": {
+      "version": "0.2.1",
+      "resolved": "https://registry.npmjs.org/@polkadot/api-format/-/api-format-0.2.1.tgz",
+      "integrity": "sha512-xv9KRA+tmMCyO0TF7UmAqZ0eT63G+q3OrH47TCXQA/+RkNUMRMkM8Z80zHpmnhXd7qSS8QqJoFn0s40VjWaXSg==",
+      "requires": {
+        "@polkadot/util": "0.2.1",
+        "babel-runtime": "6.26.0"
+      }
+    },
     "@polkadot/jsonrpc": {
       "version": "0.2.1",
       "resolved": "https://registry.npmjs.org/@polkadot/jsonrpc/-/jsonrpc-0.2.1.tgz",
@@ -1497,6 +1506,7 @@
       "requires": {
         "anymatch": "1.3.2",
         "async-each": "1.0.1",
+        "fsevents": "1.1.3",
         "glob-parent": "2.0.0",
         "inherits": "2.0.3",
         "is-binary-path": "1.0.1",
@@ -2325,6 +2335,910 @@
       "integrity": "sha1-FQStJSMVjKpA20onh8sBQRmU6k8=",
       "dev": true
     },
+    "fsevents": {
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+      "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-1.1.3.tgz",
+      "integrity": "sha512-WIr7iDkdmdbxu/Gh6eKEZJL6KPE74/5MEsf2whTOFNxbIoIixogroLdKYqB6FDav4Wavh/lZdzzd3b2KxIXC5Q==",
+      "dev": true,
+      "optional": true,
+      "requires": {
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+        "node-pre-gyp": "0.6.39"
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+            "json-stable-stringify": "1.0.1"
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+          "optional": true,
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+          }
+        },
+        "sshpk": {
+          "version": "1.13.0",
+          "bundled": true,
+          "dev": true,
+          "optional": true,
+          "requires": {
+            "asn1": "0.2.3",
+            "assert-plus": "1.0.0",
+            "bcrypt-pbkdf": "1.0.1",
+            "dashdash": "1.14.1",
+            "ecc-jsbn": "0.1.1",
+            "getpass": "0.1.7",
+            "jodid25519": "1.0.2",
+            "jsbn": "0.1.1",
+            "tweetnacl": "0.14.5"
+          },
+          "dependencies": {
+            "assert-plus": {
+              "version": "1.0.0",
+              "bundled": true,
+              "dev": true,
+              "optional": true
+            }
+          }
+        },
+        "string-width": {
+          "version": "1.0.2",
+          "bundled": true,
+          "dev": true,
+          "requires": {
+            "code-point-at": "1.1.0",
+            "is-fullwidth-code-point": "1.0.0",
+            "strip-ansi": "3.0.1"
+          }
+        },
+        "string_decoder": {
+          "version": "1.0.1",
+          "bundled": true,
+          "dev": true,
+          "requires": {
+            "safe-buffer": "5.0.1"
+          }
+        },
+        "stringstream": {
+          "version": "0.0.5",
+          "bundled": true,
+          "dev": true,
+          "optional": true
+        },
+        "strip-ansi": {
+          "version": "3.0.1",
+          "bundled": true,
+          "dev": true,
+          "requires": {
+            "ansi-regex": "2.1.1"
+          }
+        },
+        "strip-json-comments": {
+          "version": "2.0.1",
+          "bundled": true,
+          "dev": true,
+          "optional": true
+        },
+        "tar": {
+          "version": "2.2.1",
+          "bundled": true,
+          "dev": true,
+          "requires": {
+            "block-stream": "0.0.9",
+            "fstream": "1.0.11",
+            "inherits": "2.0.3"
+          }
+        },
+        "tar-pack": {
+          "version": "3.4.0",
+          "bundled": true,
+          "dev": true,
+          "optional": true,
+          "requires": {
+            "debug": "2.6.8",
+            "fstream": "1.0.11",
+            "fstream-ignore": "1.0.5",
+            "once": "1.4.0",
+            "readable-stream": "2.2.9",
+            "rimraf": "2.6.1",
+            "tar": "2.2.1",
+            "uid-number": "0.0.6"
+          }
+        },
+        "tough-cookie": {
+          "version": "2.3.2",
+          "bundled": true,
+          "dev": true,
+          "optional": true,
+          "requires": {
+            "punycode": "1.4.1"
+          }
+        },
+        "tunnel-agent": {
+          "version": "0.6.0",
+          "bundled": true,
+          "dev": true,
+          "optional": true,
+          "requires": {
+            "safe-buffer": "5.0.1"
+          }
+        },
+        "tweetnacl": {
+          "version": "0.14.5",
+          "bundled": true,
+          "dev": true,
+          "optional": true
+        },
+        "uid-number": {
+          "version": "0.0.6",
+          "bundled": true,
+          "dev": true,
+          "optional": true
+        },
+        "util-deprecate": {
+          "version": "1.0.2",
+          "bundled": true,
+          "dev": true
+        },
+        "uuid": {
+          "version": "3.0.1",
+          "bundled": true,
+          "dev": true,
+          "optional": true
+        },
+        "verror": {
+          "version": "1.3.6",
+          "bundled": true,
+          "dev": true,
+          "optional": true,
+          "requires": {
+            "extsprintf": "1.0.2"
+          }
+        },
+        "wide-align": {
+          "version": "1.1.2",
+          "bundled": true,
+          "dev": true,
+          "optional": true,
+          "requires": {
+            "string-width": "1.0.2"
+          }
+        },
+        "wrappy": {
+          "version": "1.0.2",
+          "bundled": true,
+          "dev": true
+        }
+      }
+    },
     "function-bind": {
       "version": "1.1.1",
       "resolved": "https://registry.npmjs.org/function-bind/-/function-bind-1.1.1.tgz",
@@ -3245,6 +4159,13 @@
       "integrity": "sha1-MHXOk7whuPq0PhvE2n6BFe0ee6s=",
       "dev": true
     },
+    "nan": {
+      "version": "2.8.0",
+      "resolved": "https://registry.npmjs.org/nan/-/nan-2.8.0.tgz",
+      "integrity": "sha1-7XFfP+neArV6XmJS2QqWZ14fCFo=",
+      "dev": true,
+      "optional": true
+    },
     "natural-compare": {
       "version": "1.4.0",
       "resolved": "https://registry.npmjs.org/natural-compare/-/natural-compare-1.4.0.tgz",
diff --git a/package.json b/package.json
index efacedbeee5c..eaa6e8b39a40 100644
--- a/package.json
+++ b/package.json
@@ -67,6 +67,7 @@
     "sinon-chai": "^2.14.0"
   },
   "dependencies": {
+    "@polkadot/api-format": "^0.2.0",
     "@polkadot/jsonrpc": "^0.2.0",
     "@polkadot/util": "^0.2.0",
     "babel-runtime": "^6.26.0",
diff --git a/src/api.js b/src/api.js
index 5e6e56c81846..4cdcad8c6634 100644
--- a/src/api.js
+++ b/src/api.js
@@ -5,10 +5,11 @@ import type { InterfaceDefinition } from '@polkadot/jsonrpc/src/types';
 import type { ApiInterface } from './types';
 import type { ProviderInterface } from './provider/types';
 
+const { formatInputs, formatOutput } = require('@polkadot/api-format');
 const interfaces = require('@polkadot/jsonrpc');
 const { callSignature } = require('@polkadot/jsonrpc/lib/util');
 const { isFunction } = require('@polkadot/util/lib/is');
-const { formatInputs, formatOutput } = require('./format');
+
 const { HttpProvider } = require('./provider');
 
 module.exports = class Api implements ApiInterface {
diff --git a/src/format/index.js b/src/format/index.js
deleted file mode 100644
index 18a3031f6954..000000000000
--- a/src/format/index.js
+++ /dev/null
@@ -1,10 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-// @flow
-
-const formatInputs = require('./input');
-const formatOutput = require('./output');
-
-module.exports = {
-  formatInputs,
-  formatOutput
-};
diff --git a/src/format/input/address.js b/src/format/input/address.js
deleted file mode 100644
index 9809ffc21266..000000000000
--- a/src/format/input/address.js
+++ /dev/null
@@ -1,10 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-// @flow
-
-const { formatH160 } = require('./hex');
-
-// TODO: Currently the format assumes 160-bit values (like Ethereum)
-// this will probably change along the way as things get firmed up
-module.exports = function format (value: ?string): string {
-  return formatH160(value);
-};
diff --git a/src/format/input/address.spec.js b/src/format/input/address.spec.js
deleted file mode 100644
index 954ce0b3408d..000000000000
--- a/src/format/input/address.spec.js
+++ /dev/null
@@ -1,13 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-
-const format = require('./address');
-
-describe('format/input/address', () => {
-  describe('format', () => {
-    it('pads to H160 value', () => {
-      expect(
-        format('0x1234567890')
-      ).to.equal('0x0000000000000000000000000000001234567890');
-    });
-  });
-});
diff --git a/src/format/input/hex.js b/src/format/input/hex.js
deleted file mode 100644
index 25586deff9d5..000000000000
--- a/src/format/input/hex.js
+++ /dev/null
@@ -1,33 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-// @flow
-
-const { addHexPrefix, hasHexPrefix, stripHexPrefix } = require('@polkadot/util/lib/hex');
-
-const H64_ZERO: string = '00000000000000000000000000000000';
-const H128_ZERO: string = `${H64_ZERO}${H64_ZERO}`;
-const H256_ZERO: string = `${H128_ZERO}${H128_ZERO}`;
-// const H512_ZERO: string = `${H256_ZERO}${H256_ZERO}`;
-
-function leftHexPad (value: ?string, bitLength: number): string {
-  const length = 2 * bitLength / 8;
-
-  if (hasHexPrefix(value)) {
-    value = stripHexPrefix(value);
-  }
-
-  return addHexPrefix(`${H256_ZERO}${value || ''}`.slice(-length));
-}
-
-function formatH160 (value: ?string): string {
-  return leftHexPad(value, 160);
-}
-
-function formatH256 (value: ?string): string {
-  return leftHexPad(value, 256);
-}
-
-module.exports = {
-  leftHexPad,
-  formatH160,
-  formatH256
-};
diff --git a/src/format/input/hex.spec.js b/src/format/input/hex.spec.js
deleted file mode 100644
index 5f777cefa05d..000000000000
--- a/src/format/input/hex.spec.js
+++ /dev/null
@@ -1,53 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-
-const { leftHexPad, formatH160, formatH256 } = require('./hex');
-
-describe('format/input/hex', () => {
-  describe('leftHexPad', () => {
-    it('padds to the required length', () => {
-      expect(
-        leftHexPad('0x123', 16)
-      ).to.equal('0x0123');
-    });
-
-    it('padds to the required length (no prefix)', () => {
-      expect(
-        leftHexPad('123', 16)
-      ).to.equal('0x0123');
-    });
-
-    it('pads null values correctly', () => {
-      expect(
-        leftHexPad(null, 16)
-      ).to.equal('0x0000');
-    });
-  });
-
-  describe('formatH160', () => {
-    it('pads to 40 bytes', () => {
-      expect(
-        formatH160('0x1234567890')
-      ).to.equal('0x0000000000000000000000000000001234567890');
-    });
-
-    it('pads null values correctly', () => {
-      expect(
-        formatH160(null)
-      ).to.match(/^0x(00){20,}$/);
-    });
-  });
-
-  describe('formatH256', () => {
-    it('pads to 64 bytes', () => {
-      expect(
-        formatH256('0x1234567890')
-      ).to.equal('0x0000000000000000000000000000000000000000000000000000001234567890');
-    });
-
-    it('pads null values correctly', () => {
-      expect(
-        formatH256(null)
-      ).to.match(/^0x(00){32,}$/);
-    });
-  });
-});
diff --git a/src/format/input/index.js b/src/format/input/index.js
deleted file mode 100644
index aa96545e8f65..000000000000
--- a/src/format/input/index.js
+++ /dev/null
@@ -1,24 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-// @flow
-
-import type { FormatInputType, InterfaceInputType } from '@polkadot/jsonrpc/src/types';
-import type { FormatterFunction } from '../types';
-
-const formatAddress = require('./address');
-const { formatH256 } = require('./hex');
-const formatNoop = require('../noop');
-const util = require('../util');
-
-const formatters: { [FormatInputType]: FormatterFunction } = {
-  'Address': formatAddress,
-  'CallData': formatNoop,
-  'H256': formatH256,
-  'HeaderHash': formatH256,
-  'String': formatNoop
-};
-
-module.exports = function format (inputs: Array<InterfaceInputType>, values: Array<any>): Array<any> {
-  const types = inputs.map(({ type }) => type);
-
-  return util.formatArray(formatters, types, values);
-};
diff --git a/src/format/input/index.spec.js b/src/format/input/index.spec.js
deleted file mode 100644
index 2c6c3abf3fbb..000000000000
--- a/src/format/input/index.spec.js
+++ /dev/null
@@ -1,22 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-
-const format = require('./index');
-
-describe('format/input', () => {
-  describe('format', () => {
-    it('formats each value in an array', () => {
-      expect(
-        format(
-          [
-            { name: 'foo', type: 'Address' },
-            { name: 'bar', type: 'H256' }
-          ],
-          ['0x1234', '0xabcd']
-        )
-      ).to.deep.equal([
-        '0x0000000000000000000000000000000000001234',
-        '0x000000000000000000000000000000000000000000000000000000000000abcd'
-      ]);
-    });
-  });
-});
diff --git a/src/format/noop.js b/src/format/noop.js
deleted file mode 100644
index 6fc35ab9e808..000000000000
--- a/src/format/noop.js
+++ /dev/null
@@ -1,6 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-// @flow
-
-module.exports = function format (value: any): any {
-  return value;
-};
diff --git a/src/format/noop.spec.js b/src/format/noop.spec.js
deleted file mode 100644
index 87502f00a42a..000000000000
--- a/src/format/noop.spec.js
+++ /dev/null
@@ -1,13 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-
-const format = require('./noop');
-
-describe('format/noop', () => {
-  it('returns input value as output value', () => {
-    const input = { 'some': 'object' };
-
-    expect(
-      format(input)
-    ).to.equal(input);
-  });
-});
diff --git a/src/format/output/index.js b/src/format/output/index.js
deleted file mode 100644
index d1d74151fc40..000000000000
--- a/src/format/output/index.js
+++ /dev/null
@@ -1,18 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-// @flow
-
-import type { FormatOutputType, InterfaceOutputType } from '@polkadot/jsonrpc/src/types';
-import type { FormatterFunction } from '../types';
-
-const formatNoop = require('../noop');
-const util = require('../util');
-
-const formatters: { [FormatOutputType]: FormatterFunction } = {
-  'Header': formatNoop,
-  'OutData': formatNoop,
-  'StorageData': formatNoop
-};
-
-module.exports = function format (output: InterfaceOutputType, value: any): any {
-  return util.format(formatters, output.type, value);
-};
diff --git a/src/format/output/index.spec.js b/src/format/output/index.spec.js
deleted file mode 100644
index 73ed7ff1477b..000000000000
--- a/src/format/output/index.spec.js
+++ /dev/null
@@ -1,13 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-
-const format = require('./index');
-
-describe('format/output', () => {
-  describe('format', () => {
-    it('formats the value', () => {
-      expect(
-        format('Header', 'test')
-      ).to.deep.equal('test');
-    });
-  });
-});
diff --git a/src/format/types.js b/src/format/types.js
deleted file mode 100644
index 7099809f172a..000000000000
--- a/src/format/types.js
+++ /dev/null
@@ -1,4 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-// @flow
-
-export type FormatterFunction = (value: any) => any;
diff --git a/src/format/util.js b/src/format/util.js
deleted file mode 100644
index 874263b6de20..000000000000
--- a/src/format/util.js
+++ /dev/null
@@ -1,36 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-// @flow
-
-import type { FormatterFunction } from './types';
-
-const { isUndefined } = require('@polkadot/util/lib/is');
-const formatNoop = require('./noop');
-
-function format (formatters: { [any]: FormatterFunction }, type: string, value: any): any {
-  const formatter = formatters[type];
-
-  if (isUndefined(formatter)) {
-    console.warn(`Unable to find default formatter for '${type}', falling back to noop`);
-
-    return formatNoop(value);
-  }
-
-  try {
-    return formatter(value);
-  } catch (error) {
-    throw new Error(`Error formatting '${value}' as '${type}'': ${error.message}`);
-  }
-}
-
-function formatArray (formatters: { [any]: FormatterFunction }, types: Array<string>, values: Array<any>): Array<any> {
-  return types.map((type, index) => {
-    const value = values[index];
-
-    return format(formatters, type, value);
-  });
-}
-
-module.exports = {
-  format,
-  formatArray
-};
diff --git a/src/format/util.spec.js b/src/format/util.spec.js
deleted file mode 100644
index ee6ecf29ddb4..000000000000
--- a/src/format/util.spec.js
+++ /dev/null
@@ -1,59 +0,0 @@
-// ISC, Copyright 2017 Jaco Greeff
-
-const sinon = require('sinon');
-
-const { format, formatArray } = require('./util');
-
-describe('format/util', () => {
-  let formatters;
-  let addressStub;
-  let warnSpy;
-
-  beforeEach(() => {
-    addressStub = sinon.stub();
-    formatters = {
-      'Address': addressStub,
-      'Exception': () => {
-        throw new Error('something went wrong');
-      }
-    };
-    warnSpy = sinon.spy(console, 'warn');
-  });
-
-  afterEach(() => {
-    console.warn.restore();
-  });
-
-  describe('format', () => {
-    it('formats unknown types with a fallback', () => {
-      expect(
-        format(formatters, 'Unknown', 'test')
-      ).to.equal('test');
-    });
-
-    it('logs a warning with unknown types', () => {
-      format(formatters, 'Unknown', 'test');
-      expect(warnSpy).to.have.been.calledWith("Unable to find default formatter for 'Unknown', falling back to noop");
-    });
-
-    it('formats known types using the supplied formatter', () => {
-      format(formatters, 'Address', '0xaddress');
-
-      expect(addressStub).to.have.been.calledWith('0xaddress');
-    });
-
-    it('wraps exceptions with the type', () => {
-      expect(
-        () => format(formatters, 'Exception', 'test')
-      ).to.throw(/Error formatting 'test' as 'Exception'/);
-    });
-  });
-
-  describe('formatArray', () => {
-    it('formats each value in an array', () => {
-      expect(
-        formatArray(formatters, ['Unknown', 'Unknown'], ['test', 'blah'])
-      ).to.deep.equal(['test', 'blah']);
-    });
-  });
-});
diff --git a/src/polyfill.spec.js b/src/polyfill.spec.js
new file mode 100644
index 000000000000..7bc3997a7355
--- /dev/null
+++ b/src/polyfill.spec.js
@@ -0,0 +1,15 @@
+// ISC, Copyright 2017 Jaco Greeff
+
+/* eslint-disable no-unused-expressions */
+
+describe('polyfill', () => {
+  it('adds polyfills with no exceptions', () => {
+    expect(require('./polyfill')).to.be.ok;
+  });
+
+  describe('interfaces', () => {
+    it('fetch is available', () => {
+      expect(fetch).to.be.ok;
+    });
+  });
+});
diff --git a/src/provider/ws.spec.js b/src/provider/ws.spec.js
index 8e939e0d9efa..92e32effbaa8 100644
--- a/src/provider/ws.spec.js
+++ b/src/provider/ws.spec.js
@@ -4,6 +4,7 @@
 
 const { mockWs, TEST_WS_URL } = require('../../test/mockWs');
 
+const { isUndefined } = require('@polkadot/util/lib/is');
 const sinon = require('sinon');
 
 const Ws = require('./ws');
@@ -11,8 +12,8 @@ const Ws = require('./ws');
 let ws;
 let mock;
 
-function createWs (requests, autoConnect = true) {
-  mock = autoConnect
+function createWs (requests, autoConnect) {
+  mock = autoConnect || isUndefined(autoConnect)
     ? mockWs(requests)
     : null;
 
@@ -69,6 +70,24 @@ describe('provider/Ws', () => {
 
         clock.restore();
       });
+
+      it('does not reconnect when autoConnect false', () => {
+        mock.done();
+        ws = createWs([], false);
+
+        const clock = sinon.useFakeTimers();
+
+        ws.connect = sinon.stub();
+        ws._onClose();
+
+        expect(ws.connect).not.to.have.been.called;
+
+        clock.tick(1001);
+
+        expect(ws.connect).not.to.have.been.called;
+
+        clock.restore();
+      });
     });
 
     describe('_onError', () => {