diff --git a/packages/client-wasm/src/create/imports.js b/packages/client-wasm/src/create/imports.js
index 62f66cf0..d876ae95 100644
--- a/packages/client-wasm/src/create/imports.js
+++ b/packages/client-wasm/src/create/imports.js
@@ -1,27 +1,16 @@
 // ISC, Copyright 2017-2018 Jaco Greeff
 // @flow
 
-const runtime = require('@polkadot/client-wasm-runtime');
+import type { RuntimeExports } from '@polkadot/client-wasm-runtime/types';
 
-const createMemory = require('./memory');
-const createTable = require('./table');
-
-module.exports = function createImports (imports?: WebAssemblyImports = {}, initialMemory?: number, maximumMemory?: number): WebAssemblyImports {
-  imports.env = imports.env || {};
-  imports.env.memoryBase = imports.env.memoryBase || 0;
-  imports.env.tableBase = imports.env.tableBase || 0;
-
-  if (!imports.env.memory) {
-    // $FlowFixMe imports.env gets a value above
-    imports.env.memory = createMemory(initialMemory, maximumMemory);
-  }
-
-  if (!imports.env.table) {
-    // $FlowFixMe imports.env gets a value above
-    imports.env.table = createTable();
-  }
-
-  imports.env = Object.assign(imports.env, runtime(imports.env.memory));
-
-  return imports;
+// flowlint-next-line unclear-type:off
+module.exports = function createImports (memory: WebAssembly.Memory, table: WebAssembly.Table, runtime: RuntimeExports, imports?: Object = {}): WebAssemblyImports {
+  return Object.assign({}, imports, {
+    env: Object.assign({}, runtime, {
+      memory,
+      memoryBase: 0,
+      table,
+      tableBase: 0
+    })
+  });
 };
diff --git a/packages/client-wasm/src/create/imports.spec.js b/packages/client-wasm/src/create/imports.spec.js
index 160de8fc..8453c9ae 100644
--- a/packages/client-wasm/src/create/imports.spec.js
+++ b/packages/client-wasm/src/create/imports.spec.js
@@ -1,116 +1,42 @@
 // ISC, Copyright 2017-2018 Jaco Greeff
 
-const runtime = require('@polkadot/client-wasm-runtime');
-const isInstanceOf = require('@polkadot/util/is/instanceOf');
-
 const { createImports } = require('./index');
 
 describe('createImports', () => {
-  let imports;
-  let origWebAssembly;
-  let memOptions;
-
-  beforeEach(() => {
-    imports = {};
-    origWebAssembly = global.WebAssembly;
-
-    global.WebAssembly = class {
-      static Memory = class {
-        constructor (options) {
-          this.buffer = new Uint8Array(10);
-          memOptions = options;
-        }
-      };
-      static Table = class {};
-    };
-  });
-
-  afterEach(() => {
-    global.WebAssembly = origWebAssembly;
-  });
-
-  it('works when import has not been specified', () => {
+  it('sets the memoryBase & tableBase', () => {
     expect(
-      createImports()
-    ).toBeDefined();
-  });
-
-  it('exposes the default imports on env', () => {
-    expect(
-      createImports({}).env
-    ).toMatchObject(
-      Object.keys(runtime).reduce((env, key) => {
-        env[key] = expect.anything();
-
-        return env;
-      }, {})
-    );
-  });
-
-  it('uses env.memoryBase when supplied', () => {
-    imports.env = { memoryBase: 'test' };
-    imports = createImports(imports);
-
-    expect(imports.env.memoryBase).toEqual('test');
-  });
-
-  it('uses env.tableBase when supplied', () => {
-    imports.env = { tableBase: 'test' };
-    imports = createImports(imports);
-
-    expect(imports.env.tableBase).toEqual('test');
-  });
-
-  it('uses env.memory when supplied', () => {
-    const memory = { buffer: new Uint8Array(10) };
-
-    imports.env = { memory };
-    imports = createImports(imports);
-
-    expect(imports.env.memory).toEqual(memory);
+      createImports({}, {}, {}).env
+    ).toMatchObject({
+      memoryBase: 0,
+      tableBase: 0
+    });
   });
 
-  it('creates env.memory when none supplied', () => {
-    imports = createImports(imports);
+  it('uses supplied memory', () => {
+    const memory = { 'some': { 'memory': { 'object': true } } };
 
     expect(
-      isInstanceOf(
-        imports.env.memory, WebAssembly.Memory
-      )
-    ).toEqual(true);
+      createImports(memory, {}, {}).env
+    ).toMatchObject({
+      memory
+    });
   });
 
-  it('creates env.memory using the supplied initial/maximum', () => {
-    createImports(imports, 4, 6);
+  it('uses supplied table', () => {
+    const table = { 'some': { 'table': { 'object': true } } };
 
     expect(
-      memOptions
-    ).toEqual({
-      initial: (4 * 1024) / 64,
-      maximum: (6 * 1024) / 64
+      createImports({}, table, {}).env
+    ).toMatchObject({
+      table
     });
   });
 
-  it('uses env.table when supplied', () => {
-    imports.env = { table: 'test' };
-    imports = createImports(imports);
-
-    expect(imports.env.table).toEqual('test');
-  });
-
-  it('creates env.table when none supplied', () => {
-    imports = createImports(imports);
+  it('exposes the runtime imports on the env', () => {
+    const runtime = { 'ext_foo': 1, 'ext_bar': 2, 'ext_baz': 3 };
 
     expect(
-      isInstanceOf(
-        imports.env.table, WebAssembly.Table
-      )
-    ).toEqual(true);
-  });
-
-  it('sets default environment when none supplied', () => {
-    imports = createImports();
-
-    expect(imports.env).toBeDefined();
+      createImports({}, {}, runtime).env
+    ).toMatchObject(runtime);
   });
 });
diff --git a/packages/client-wasm/src/create/instance.js b/packages/client-wasm/src/create/instance.js
index ba3af284..4872c75f 100644
--- a/packages/client-wasm/src/create/instance.js
+++ b/packages/client-wasm/src/create/instance.js
@@ -1,6 +1,6 @@
 // ISC, Copyright 2017-2018 Jaco Greeff
 // @flow
 
-module.exports = function createInstance (module: WebAssemblyModule, imports: WebAssemblyImports): WebAssemblyInstance {
-  return new WebAssembly.Instance(module, imports);
+module.exports = function createInstance (wasmModule: WebAssemblyModule, imports: WebAssemblyImports): WebAssemblyInstance {
+  return new WebAssembly.Instance(wasmModule, imports);
 };
diff --git a/packages/client-wasm/src/index.js b/packages/client-wasm/src/index.js
index d4214e6d..db8e0049 100644
--- a/packages/client-wasm/src/index.js
+++ b/packages/client-wasm/src/index.js
@@ -1,6 +1,6 @@
 // ISC, Copyright 2017-2018 Jaco Greeff
 // @flow
 
-const Wasm = require('./wasm');
+const wasm = require('./wasm');
 
-module.exports = Wasm;
+module.exports = wasm;
diff --git a/packages/client-wasm/src/wasm.js b/packages/client-wasm/src/wasm.js
index a499a40c..ea58e31e 100644
--- a/packages/client-wasm/src/wasm.js
+++ b/packages/client-wasm/src/wasm.js
@@ -1,31 +1,21 @@
 // ISC, Copyright 2017-2018 Jaco Greeff
 // @flow
 
-const assert = require('@polkadot/util/assert');
-const isObject = require('@polkadot/util/is/object');
+import type { ConfigType } from '@polkadot/client/types';
+import type { DbInterface } from '@polkadot/client-db/types';
+import type { WasmExtraImports } from './types';
 
-const { createImports, createInstance, createModule } = require('./create');
+const createRuntime = require('@polkadot/client-wasm-runtime');
 
-module.exports = class Wasm {
-  constructor (instance: WebAssemblyInstance) {
-    const exports = instance.exports;
+const { createImports, createInstance, createMemory, createModule, createTable } = require('./create');
 
-    assert(isObject(exports), 'Expected function exports');
+module.exports = function wasm ({ wasm: { memoryInitial, memoryMaximum } }: ConfigType, db: DbInterface, bytecode: Uint8Array, imports?: WasmExtraImports = {}): WebAssemblyInstance$Exports {
+  const memory = createMemory(memoryInitial, memoryMaximum);
+  const table = createTable();
+  const runtime = createRuntime(memory, db);
 
-    Object.keys(exports).forEach((key: string) => {
-      Object.defineProperty(this, key, {
-        configurable: false,
-        enumerable: true,
-        value: exports[key]
-      });
-    });
-  }
-
-  static fromCode (bytecode: Uint8Array, _imports?: WebAssemblyImports): Wasm {
-    const module = createModule(bytecode);
-    const imports = createImports(_imports);
-    const instance = createInstance(module, imports);
-
-    return new Wasm(instance);
-  }
+  return createInstance(
+    createModule(bytecode),
+    createImports(memory, table, runtime, imports)
+  ).exports;
 };
diff --git a/packages/client-wasm/src/wasm.spec.js b/packages/client-wasm/src/wasm.spec.js
index fe2e2838..e636ba10 100644
--- a/packages/client-wasm/src/wasm.spec.js
+++ b/packages/client-wasm/src/wasm.spec.js
@@ -1,95 +1,60 @@
 // ISC, Copyright 2017-2018 Jaco Greeff
 
-const isInstanceOf = require('@polkadot/util/is/instanceOf');
-
 const { loadWasm } = require('../test/helpers');
-const Wasm = require('./wasm');
+const wasm = require('./wasm');
 
-describe('Wasm', () => {
-  describe('checks', () => {
-    let origWebAssembly;
+describe('wasm', () => {
+  let instance;
 
+  describe('valid modules', () => {
     beforeEach(() => {
-      origWebAssembly = global.WebAssembly;
-
-      global.WebAssembly = class {
-        static Module = class {};
-        static Memory = class {};
-        static Table = class {};
-        static Instance = class {};
-      };
-    });
-
-    afterEach(() => {
-      global.WebAssembly = origWebAssembly;
+      instance = wasm(
+        { wasm: {} }, {},
+        loadWasm('addTwo.wasm')
+      );
     });
 
-    it('disallows empty exports', () => {
+    it('allows calls into the module', () => {
       expect(
-        () => new Wasm(new WebAssembly.Instance())
-      ).toThrow(/Expected function exports/);
+        instance.addTwo(22, 33)
+      ).toEqual(55);
     });
   });
 
-  describe('instance', () => {
-    let wasm;
+  describe('imports', () => {
+    let callback;
+    let instance;
 
-    describe('valid modules', () => {
-      beforeEach(() => {
-        wasm = Wasm.fromCode(
-          loadWasm('addTwo.wasm')
-        );
-      });
-
-      it('creates a valid instance via fromCode', () => {
-        expect(
-          isInstanceOf(wasm, Wasm)
-        ).toEqual(true);
-      });
-
-      it('allows calls into the module', () => {
-        expect(
-          wasm.addTwo(22, 33)
-        ).toEqual(55);
-      });
+    beforeEach(() => {
+      callback = jest.fn();
+      instance = wasm(
+        { wasm: {} }, {},
+        loadWasm('import.wasm'),
+        { js: { callback } }
+      );
     });
 
-    describe('imports', () => {
-      let callback;
-      let wasm;
+    it('allows imports to be called', () => {
+      instance.go(123);
 
-      beforeEach(() => {
-        callback = jest.fn();
-        wasm = Wasm.fromCode(
-          loadWasm('import.wasm'),
-          { js: { callback } }
-        );
-      });
-
-      it('allows imports to be called', () => {
-        wasm.go(123);
-
-        expect(callback).toHaveBeenCalledWith(123);
-      });
+      expect(callback).toHaveBeenCalledWith(123);
     });
+  });
 
-    describe('start', () => {
-      let callback;
-      // let wasm;
-
-      beforeEach(() => {
-        callback = jest.fn();
-        Wasm.fromCode(
-          loadWasm('start.wasm'),
-          { js: { callback } }
-        );
-      });
+  describe('start', () => {
+    let callback;
 
-      it('allows imports to be called', () => {
-        // wasm.go(123);
+    beforeEach(() => {
+      callback = jest.fn();
+      instance = wasm(
+        { wasm: {} }, {},
+        loadWasm('start.wasm'),
+        { js: { callback } }
+      );
+    });
 
-        expect(callback).toHaveBeenCalledWith(1337);
-      });
+    it('allows imports to be called', () => {
+      expect(callback).toHaveBeenCalledWith(1337);
     });
   });
 });
diff --git a/packages/client/src/types.js b/packages/client/src/types.js
index fdbd576a..708915a1 100644
--- a/packages/client/src/types.js
+++ b/packages/client/src/types.js
@@ -5,6 +5,7 @@ import type { ChainNameType } from '@polkadot/client-chains/types';
 import type { DbConfigType } from '@polkadot/client-db/types';
 import type { P2pConfigType } from '@polkadot/client-p2p/types';
 import type { RpcConfigType, HandlerType } from '@polkadot/client-rpc/types';
+import type { WasmConfigType } from '@polkadot/client-wasm/types';
 import type { RoleType } from '@polkadot/primitives/role';
 
 export type ConfigType = {
@@ -12,7 +13,8 @@ export type ConfigType = {
   db: DbConfigType,
   p2p: P2pConfigType,
   rpc: RpcConfigType,
-  roles: Array<RoleType>
+  roles: Array<RoleType>,
+  wasm: WasmConfigType
 };
 
 export type EndpointType = {