From 99c3bc11631a713c60c9aa2fbe52b716a3ba7add Mon Sep 17 00:00:00 2001
From: Liam Horne <snario@users.noreply.github.com>
Date: Wed, 26 Dec 2018 12:36:17 +0000
Subject: [PATCH] Replace ethers usage to always import from module (#364)

* Replace all ethers utils with module imports

* Fixed a few places I missed the first time

* Update rollup for cf.js to include ethers.constants
---
 packages/cf.js/rollup.config.js               |  3 +-
 packages/cf.js/src/legacy/app-instance.ts     | 12 ++++----
 packages/cf.js/src/legacy/app/index.ts        | 16 +++++------
 .../src/legacy/eth-balance-refund-app.ts      |  9 ++----
 packages/cf.js/src/legacy/node/index.ts       |  4 +--
 packages/cf.js/src/legacy/types.ts            |  4 +--
 .../cf.js/src/legacy/utils/free-balance.ts    | 15 +++++-----
 .../cf.js/src/legacy/utils/peer-balance.ts    | 17 +++++------
 packages/cf.js/src/legacy/utils/serializer.ts |  4 +--
 packages/cf.js/src/utils/abi.ts               | 10 +++----
 packages/cf.js/src/utils/signature.ts         | 22 ++++++++-------
 packages/cf.js/test/app-factory.spec.ts       | 14 +++++-----
 packages/cf.js/test/utils/signature.spec.ts   |  8 +++---
 packages/contracts/test/app-registry.spec.ts  | 28 +++++++++----------
 packages/node/src/channels.ts                 |  4 +--
 packages/node/src/models.ts                   |  7 ++---
 packages/node/src/node.ts                     |  6 ++--
 packages/node/src/utils.ts                    |  8 ++----
 .../integration/get-app-instances.spec.ts     |  4 +--
 .../integration/node-communication.spec.ts    |  4 +--
 .../node/test/integration/node-store.spec.ts  | 18 ++++--------
 packages/node/test/integration/utils.ts       |  8 +++---
 22 files changed, 104 insertions(+), 121 deletions(-)

diff --git a/packages/cf.js/rollup.config.js b/packages/cf.js/rollup.config.js
index 48496a738..c45191c6c 100644
--- a/packages/cf.js/rollup.config.js
+++ b/packages/cf.js/rollup.config.js
@@ -17,7 +17,8 @@ export default {
       format: "iife",
       exports: "named",
       globals: {
-        "ethers/utils": "ethers.utils"
+        "ethers/utils": "ethers.utils",
+        "ethers/constants": "ethers.constants"
       }
     }
   ],
diff --git a/packages/cf.js/src/legacy/app-instance.ts b/packages/cf.js/src/legacy/app-instance.ts
index 09a57e48b..2a2b7241f 100644
--- a/packages/cf.js/src/legacy/app-instance.ts
+++ b/packages/cf.js/src/legacy/app-instance.ts
@@ -1,4 +1,4 @@
-import { ethers } from "ethers";
+import { formatParamType, Interface, ParamType } from "ethers/utils";
 
 import { Terms } from "./app";
 import { AbiEncodings, AppDefinition } from "./types";
@@ -13,25 +13,23 @@ export class AppInstance {
 
   // TODO: temp hack necessary until ethers support https://github.com/ethers-io/ethers.js/issues/325
   static generateAbiEncodings(
-    abi: string | (string | ethers.utils.ParamType)[]
+    abi: string | (string | ParamType)[]
   ): AbiEncodings {
-    const iface = new ethers.utils.Interface(abi);
+    const iface = new Interface(abi);
     const appFunctionNames = Object.keys(iface.functions).filter(fn => {
       return fn.indexOf("(") === -1;
     });
     const appActions = appFunctionNames.map(fn => {
       const inputs = iface.functions[fn].inputs;
       const tuples = inputs.map(input => {
-        return ethers.utils.formatParamType(input);
+        return formatParamType(input);
       });
 
       return `${fn}(${tuples.join(",")})`;
     });
 
     return {
-      appStateEncoding: ethers.utils.formatParamType(
-        iface.functions.resolve.inputs[0]
-      ),
+      appStateEncoding: formatParamType(iface.functions.resolve.inputs[0]),
       appActionEncoding: JSON.stringify([appActions.join(",")])
     };
   }
diff --git a/packages/cf.js/src/legacy/app/index.ts b/packages/cf.js/src/legacy/app/index.ts
index b7bb40e56..96f388661 100644
--- a/packages/cf.js/src/legacy/app/index.ts
+++ b/packages/cf.js/src/legacy/app/index.ts
@@ -1,5 +1,5 @@
-import { ethers } from "ethers";
-import { defaultAbiCoder, keccak256 } from "ethers/utils";
+import { HashZero } from "ethers/constants";
+import { BigNumber, defaultAbiCoder, keccak256 } from "ethers/utils";
 
 import * as abi from "../../utils/abi";
 import { StateChannelInfo } from "../channel";
@@ -67,7 +67,7 @@ export class AppInterface {
       console.error(
         "WARNING: Can't compute hash for AppInterface because its address is 0x0"
       );
-      return ethers.constants.HashZero;
+      return HashZero;
     }
     return keccak256(
       abi.encode(
@@ -91,7 +91,7 @@ export class AppInterface {
 export class Terms {
   constructor(
     readonly assetType: number,
-    readonly limit: ethers.utils.BigNumber,
+    readonly limit: BigNumber,
     readonly token: Address
   ) {}
 
@@ -118,8 +118,8 @@ export interface UpdateData {
 }
 
 export interface UninstallOptions {
-  peerABalance: ethers.utils.BigNumber;
-  peerBBalance: ethers.utils.BigNumber;
+  peerABalance: BigNumber;
+  peerBBalance: BigNumber;
 }
 
 export interface InstallData {
@@ -138,8 +138,8 @@ export interface InstallOptions {
   stateEncoding: string;
   abiEncoding: string;
   state: object;
-  peerABalance: ethers.utils.BigNumber;
-  peerBBalance: ethers.utils.BigNumber;
+  peerABalance: BigNumber;
+  peerBBalance: BigNumber;
 }
 
 export interface AppInstanceInfo {
diff --git a/packages/cf.js/src/legacy/eth-balance-refund-app.ts b/packages/cf.js/src/legacy/eth-balance-refund-app.ts
index 150cc03f7..c01630db0 100644
--- a/packages/cf.js/src/legacy/eth-balance-refund-app.ts
+++ b/packages/cf.js/src/legacy/eth-balance-refund-app.ts
@@ -1,6 +1,5 @@
 import BuildArtifact from "@counterfactual/contracts/build/contracts/ETHBalanceRefundApp.json";
-
-import { ethers } from "ethers";
+import { AddressZero, Zero } from "ethers/constants";
 
 import { Terms } from "./app";
 import { AppInstance } from "./app-instance";
@@ -9,11 +8,7 @@ import { AppDefinition } from "./types";
 export class ETHBalanceRefundApp extends AppInstance {
   constructor(appAddress: string, signingKeys: string[]) {
     const timeout = 100;
-    const terms = new Terms(
-      0,
-      ethers.utils.bigNumberify("0"),
-      ethers.constants.AddressZero
-    );
+    const terms = new Terms(0, Zero, AddressZero);
     const abiEncodings = AppInstance.generateAbiEncodings(BuildArtifact.abi);
 
     const appDefinition: AppDefinition = {
diff --git a/packages/cf.js/src/legacy/node/index.ts b/packages/cf.js/src/legacy/node/index.ts
index 580456f89..74c836736 100644
--- a/packages/cf.js/src/legacy/node/index.ts
+++ b/packages/cf.js/src/legacy/node/index.ts
@@ -1,4 +1,4 @@
-import { ethers } from "ethers";
+import { Signature } from "ethers/utils";
 
 // FIXME: move operation action names away from client action names
 // https://github.com/counterfactual/monorepo/issues/144
@@ -47,5 +47,5 @@ export interface ClientActionMessage {
   toAddress: string;
   fromAddress: string;
   seq: number;
-  signature?: ethers.utils.Signature;
+  signature?: Signature;
 }
diff --git a/packages/cf.js/src/legacy/types.ts b/packages/cf.js/src/legacy/types.ts
index 1c9ee5224..c9705241f 100644
--- a/packages/cf.js/src/legacy/types.ts
+++ b/packages/cf.js/src/legacy/types.ts
@@ -1,4 +1,4 @@
-import { ethers } from "ethers";
+import { BigNumber } from "ethers/utils";
 
 export interface AppDefinition {
   address: string;
@@ -12,7 +12,7 @@ export interface AbiEncodings {
 }
 
 export interface Deposits {
-  [s: string]: ethers.utils.BigNumber;
+  [s: string]: BigNumber;
 }
 
 export type DeserializationCondition = {
diff --git a/packages/cf.js/src/legacy/utils/free-balance.ts b/packages/cf.js/src/legacy/utils/free-balance.ts
index 5a8de434c..ad663a619 100644
--- a/packages/cf.js/src/legacy/utils/free-balance.ts
+++ b/packages/cf.js/src/legacy/utils/free-balance.ts
@@ -1,4 +1,5 @@
-import { ethers } from "ethers";
+import { AddressZero } from "ethers/constants";
+import { BigNumber, Interface, parseEther } from "ethers/utils";
 
 import { AppInterface, Terms } from "../app";
 
@@ -15,14 +16,14 @@ export class FreeBalance {
     // https://github.com/counterfactual/monorepo/issues/118
     return new Terms(
       0, // 0 means ETH
-      ethers.utils.parseEther("0.001"), // FIXME: un-hardcode (https://github.com/counterfactual/monorepo/issues/117)
-      ethers.constants.AddressZero
+      parseEther("0.001"), // FIXME: un-hardcode (https://github.com/counterfactual/monorepo/issues/117)
+      AddressZero
     );
   }
 
   public static contractInterface(address: string): AppInterface {
     const applyAction = "0x00000000"; // not used
-    const resolver = new ethers.utils.Interface([
+    const resolver = new Interface([
       // TODO: Put this somewhere eh
       // https://github.com/counterfactual/monorepo/issues/134
       "resolve(tuple(address,address,uint256,uint256),tuple(uint8,uint256,address))"
@@ -41,16 +42,16 @@ export class FreeBalance {
 
   constructor(
     readonly alice: Address, // first person in free balance object
-    readonly aliceBalance: ethers.utils.BigNumber,
+    readonly aliceBalance: BigNumber,
     readonly bob: Address, // second person in free balance object
-    readonly bobBalance: ethers.utils.BigNumber,
+    readonly bobBalance: BigNumber,
     readonly uniqueId: number,
     readonly localNonce: number,
     readonly timeout: number,
     readonly dependencyNonce: Nonce
   ) {}
 
-  public balanceOfAddress(address: Address): ethers.utils.BigNumber {
+  public balanceOfAddress(address: Address): BigNumber {
     if (address === this.alice) return this.aliceBalance;
     if (address === this.bob) return this.bobBalance;
     throw Error(`address ${address} not in free balance`);
diff --git a/packages/cf.js/src/legacy/utils/peer-balance.ts b/packages/cf.js/src/legacy/utils/peer-balance.ts
index 0ce932df1..cf222e2a3 100644
--- a/packages/cf.js/src/legacy/utils/peer-balance.ts
+++ b/packages/cf.js/src/legacy/utils/peer-balance.ts
@@ -1,6 +1,6 @@
-import { ethers } from "ethers";
+import { BigNumber, bigNumberify } from "ethers/utils";
 
-import { Address } from ".";
+import { Address } from "./index";
 
 export class PeerBalance {
   /**
@@ -8,9 +8,9 @@ export class PeerBalance {
    */
   public static balances(
     address1: Address,
-    balance1: ethers.utils.BigNumber,
+    balance1: BigNumber,
     address2: Address,
-    balance2: ethers.utils.BigNumber
+    balance2: BigNumber
   ): CanonicalPeerBalance {
     if (address2.localeCompare(address1) < 0) {
       return new CanonicalPeerBalance(
@@ -61,13 +61,10 @@ export class PeerBalance {
       )
     ];
   }
-  public balance: ethers.utils.BigNumber;
+  public balance: BigNumber;
 
-  constructor(
-    readonly address: Address,
-    balance: number | ethers.utils.BigNumber
-  ) {
-    this.balance = ethers.utils.bigNumberify(balance.toString());
+  constructor(readonly address: Address, balance: number | BigNumber) {
+    this.balance = bigNumberify(balance.toString());
   }
 }
 
diff --git a/packages/cf.js/src/legacy/utils/serializer.ts b/packages/cf.js/src/legacy/utils/serializer.ts
index 04e463a9e..34bfcc990 100644
--- a/packages/cf.js/src/legacy/utils/serializer.ts
+++ b/packages/cf.js/src/legacy/utils/serializer.ts
@@ -1,4 +1,4 @@
-import { ethers } from "ethers";
+import { bigNumberify } from "ethers/utils";
 
 import { DeserializationCase } from "../types";
 
@@ -24,7 +24,7 @@ const isSignature = data =>
 
 const deserializeArray = data => data.map(value => deserialize(value));
 
-const deserializeBigNumber = data => ethers.utils.bigNumberify(data._hex);
+const deserializeBigNumber = data => bigNumberify(data._hex);
 
 const identity = data => data;
 
diff --git a/packages/cf.js/src/utils/abi.ts b/packages/cf.js/src/utils/abi.ts
index e4ec5d6e1..8b4b4faf2 100644
--- a/packages/cf.js/src/utils/abi.ts
+++ b/packages/cf.js/src/utils/abi.ts
@@ -1,13 +1,13 @@
-import { ethers } from "ethers";
+import { Arrayish, defaultAbiCoder, solidityPack } from "ethers/utils";
 
 export function encode(types: string[], values: any[]) {
-  return ethers.utils.defaultAbiCoder.encode(types, values);
+  return defaultAbiCoder.encode(types, values);
 }
 
-export function decode(types: string[], data: ethers.utils.Arrayish) {
-  return ethers.utils.defaultAbiCoder.decode(types, data);
+export function decode(types: string[], data: Arrayish) {
+  return defaultAbiCoder.decode(types, data);
 }
 
 export function encodePacked(types: string[], values: any[]) {
-  return ethers.utils.solidityPack(types, values);
+  return solidityPack(types, values);
 }
diff --git a/packages/cf.js/src/utils/signature.ts b/packages/cf.js/src/utils/signature.ts
index 16cf8042a..abd069b15 100644
--- a/packages/cf.js/src/utils/signature.ts
+++ b/packages/cf.js/src/utils/signature.ts
@@ -1,12 +1,14 @@
-import { ethers } from "ethers";
-
 import { Bytes32 } from "@counterfactual/common-types";
+import {
+  BigNumber,
+  joinSignature,
+  recoverAddress,
+  Signature
+} from "ethers/utils";
 
-export function signaturesToBytes(
-  ...signatures: ethers.utils.Signature[]
-): string {
+export function signaturesToBytes(...signatures: Signature[]): string {
   const signaturesHexString = signatures
-    .map(ethers.utils.joinSignature)
+    .map(joinSignature)
     .map(s => s.substr(2))
     .join("");
   return `0x${signaturesHexString}`;
@@ -14,13 +16,13 @@ export function signaturesToBytes(
 
 export function signaturesToSortedBytes(
   digest: Bytes32,
-  ...signatures: ethers.utils.Signature[]
+  ...signatures: Signature[]
 ): string {
   const sigs = signatures.slice();
   sigs.sort((sigA, sigB) => {
-    const addrA = ethers.utils.recoverAddress(digest, signaturesToBytes(sigA));
-    const addrB = ethers.utils.recoverAddress(digest, signaturesToBytes(sigB));
-    return new ethers.utils.BigNumber(addrA).lt(addrB) ? -1 : 1;
+    const addrA = recoverAddress(digest, signaturesToBytes(sigA));
+    const addrB = recoverAddress(digest, signaturesToBytes(sigB));
+    return new BigNumber(addrA).lt(addrB) ? -1 : 1;
   });
   return signaturesToBytes(...sigs);
 }
diff --git a/packages/cf.js/test/app-factory.spec.ts b/packages/cf.js/test/app-factory.spec.ts
index 9a4e5bfdf..afbbe2e5a 100644
--- a/packages/cf.js/test/app-factory.spec.ts
+++ b/packages/cf.js/test/app-factory.spec.ts
@@ -1,5 +1,5 @@
 import { AssetType, Node } from "@counterfactual/common-types";
-import { ethers } from "ethers";
+import { parseEther } from "ethers/utils";
 
 import { AppFactory } from "../src/app-factory";
 import { Provider } from "../src/provider";
@@ -37,7 +37,7 @@ describe("CF.js AppFactory", () => {
         expect(request.type).toBe(Node.MethodName.PROPOSE_INSTALL);
         const params = request.params as Node.ProposeInstallParams;
         expect(params.initialState).toBe(testState);
-        expect(params.myDeposit).toEqual(ethers.utils.parseEther("0.5"));
+        expect(params.myDeposit).toEqual(parseEther("0.5"));
         nodeProvider.simulateMessageFromNode({
           type: Node.MethodName.PROPOSE_INSTALL,
           requestId: request.requestId,
@@ -51,8 +51,8 @@ describe("CF.js AppFactory", () => {
         asset: {
           assetType: AssetType.ETH
         },
-        peerDeposit: ethers.utils.parseEther("0.5"),
-        myDeposit: ethers.utils.parseEther("0.5"),
+        peerDeposit: parseEther("0.5"),
+        myDeposit: parseEther("0.5"),
         timeout: "100",
         initialState: testState
       });
@@ -66,8 +66,8 @@ describe("CF.js AppFactory", () => {
           asset: {
             assetType: AssetType.ETH
           },
-          peerDeposit: ethers.utils.parseEther("0.5"),
-          myDeposit: ethers.utils.parseEther("0.5"),
+          peerDeposit: parseEther("0.5"),
+          myDeposit: parseEther("0.5"),
           timeout: "100",
           initialState: "4000"
         });
@@ -86,7 +86,7 @@ describe("CF.js AppFactory", () => {
           asset: {
             assetType: AssetType.ETH
           },
-          peerDeposit: ethers.utils.parseEther("0.5"),
+          peerDeposit: parseEther("0.5"),
           myDeposit: "$%GARBAGE$%",
           timeout: "100",
           initialState: "4000"
diff --git a/packages/cf.js/test/utils/signature.spec.ts b/packages/cf.js/test/utils/signature.spec.ts
index 8700fb19d..c4e981bc2 100644
--- a/packages/cf.js/test/utils/signature.spec.ts
+++ b/packages/cf.js/test/utils/signature.spec.ts
@@ -1,14 +1,14 @@
-import { ethers } from "ethers";
+import { keccak256, SigningKey, toUtf8Bytes } from "ethers/utils";
 
 import { signaturesToBytes, signaturesToSortedBytes } from "../../src/utils";
 
 const privateKey =
   "0x0123456789012345678901234567890123456789012345678901234567890123";
-const signingKey = new ethers.utils.SigningKey(privateKey);
+const signingKey = new SigningKey(privateKey);
 
 const signaturesAndDigests = ["sig1", "sig3", "sig2"].map(message => {
-  const bytes = ethers.utils.toUtf8Bytes(message);
-  const digest = ethers.utils.keccak256(bytes);
+  const bytes = toUtf8Bytes(message);
+  const digest = keccak256(bytes);
   const signature = signingKey.signDigest(digest);
 
   return {
diff --git a/packages/contracts/test/app-registry.spec.ts b/packages/contracts/test/app-registry.spec.ts
index f4e741553..6ea6c9ca9 100644
--- a/packages/contracts/test/app-registry.spec.ts
+++ b/packages/contracts/test/app-registry.spec.ts
@@ -1,5 +1,6 @@
-import { ethers } from "ethers";
-import { Web3Provider } from "ethers/providers";
+import { Contract, ContractFactory } from "ethers";
+import { AddressZero, HashZero } from "ethers/constants";
+import { JsonRpcSigner, Web3Provider } from "ethers/providers";
 import { hexlify, randomBytes } from "ethers/utils";
 
 import { ALICE, BOB } from "./constants";
@@ -16,9 +17,9 @@ import {
 const ONCHAIN_CHALLENGE_TIMEOUT = 30;
 
 contract("AppRegistry", (accounts: string[]) => {
-  let provider: ethers.providers.Web3Provider;
-  let wallet: ethers.providers.JsonRpcSigner;
-  let appRegistry: ethers.Contract;
+  let provider: Web3Provider;
+  let wallet: JsonRpcSigner;
+  let appRegistry: Contract;
 
   let setStateAsOwner: (nonce: number, appState?: string) => Promise<void>;
   let setStateWithSignatures: (
@@ -40,7 +41,7 @@ contract("AppRegistry", (accounts: string[]) => {
     artifact.link(artifacts.require("LibStaticCall"));
     artifact.link(artifacts.require("Transfer"));
 
-    appRegistry = await new ethers.ContractFactory(
+    appRegistry = await new ContractFactory(
       artifact.abi,
       artifact.binary,
       wallet
@@ -60,7 +61,7 @@ contract("AppRegistry", (accounts: string[]) => {
         hexlify(randomBytes(4)),
         hexlify(randomBytes(4))
       ),
-      new Terms(AssetType.ETH, 0, ethers.constants.AddressZero),
+      new Terms(AssetType.ETH, 0, AddressZero),
       10
     );
 
@@ -77,26 +78,23 @@ contract("AppRegistry", (accounts: string[]) => {
     setStateAsOwner = (nonce: number, appState?: string) =>
       appRegistry.functions.setState(appInstance.appIdentity, {
         nonce,
-        stateHash: appState || ethers.constants.HashZero,
+        stateHash: appState || HashZero,
         timeout: ONCHAIN_CHALLENGE_TIMEOUT,
-        signatures: ethers.constants.HashZero
+        signatures: HashZero
       });
 
     cancelChallenge = () =>
-      appRegistry.functions.cancelChallenge(
-        appInstance.appIdentity,
-        ethers.constants.HashZero
-      );
+      appRegistry.functions.cancelChallenge(appInstance.appIdentity, HashZero);
 
     setStateWithSignatures = async (nonce: number, appState?: string) =>
       appRegistry.functions.setState(appInstance.appIdentity, {
         nonce,
-        stateHash: appState || ethers.constants.HashZero,
+        stateHash: appState || HashZero,
         timeout: ONCHAIN_CHALLENGE_TIMEOUT,
         signatures: await wallet.signMessage(
           computeStateHash(
             appInstance.id,
-            appState || ethers.constants.HashZero,
+            appState || HashZero,
             nonce,
             ONCHAIN_CHALLENGE_TIMEOUT
           )
diff --git a/packages/node/src/channels.ts b/packages/node/src/channels.ts
index c80607251..33689697c 100644
--- a/packages/node/src/channels.ts
+++ b/packages/node/src/channels.ts
@@ -1,5 +1,5 @@
 import { Address, AppInstanceInfo, Node } from "@counterfactual/common-types";
-import { ethers } from "ethers";
+import { Wallet } from "ethers";
 import { v4 as generateUUID } from "uuid";
 
 import { APP_INSTANCE_STATUS, Channel } from "./models";
@@ -447,6 +447,6 @@ export class Channels {
 
   private generateNewMultisigAddress(owners: Address[]): Address {
     // TODO: implement this using CREATE2
-    return ethers.Wallet.createRandom().address;
+    return Wallet.createRandom().address;
   }
 }
diff --git a/packages/node/src/models.ts b/packages/node/src/models.ts
index 5f86e2040..0ecf15c5b 100644
--- a/packages/node/src/models.ts
+++ b/packages/node/src/models.ts
@@ -4,8 +4,7 @@ import {
   AppInstanceInfo,
   AssetType
 } from "@counterfactual/common-types";
-
-import { zeroBalance } from "./utils";
+import { Zero } from "ethers/constants";
 
 import Nonce = legacy.utils.Nonce;
 import FreeBalance = legacy.utils.FreeBalance;
@@ -93,9 +92,9 @@ export class Channel {
     // TODO: extend to all asset types
     const ethFreeBalance = new FreeBalance(
       multisigOwners[0],
-      zeroBalance,
+      Zero,
       multisigOwners[1],
-      zeroBalance,
+      Zero,
       0,
       0,
       0,
diff --git a/packages/node/src/node.ts b/packages/node/src/node.ts
index 601cefbb9..89dd5d8a3 100644
--- a/packages/node/src/node.ts
+++ b/packages/node/src/node.ts
@@ -1,5 +1,5 @@
 import { Address, Node as NodeTypes } from "@counterfactual/common-types";
-import { ethers } from "ethers";
+import { SigningKey } from "ethers/utils";
 import EventEmitter from "eventemitter3";
 
 import { Channels } from "./channels";
@@ -22,7 +22,7 @@ export class Node {
   private readonly outgoing: EventEmitter;
 
   private readonly channels: Channels;
-  private readonly signer: ethers.utils.SigningKey;
+  private readonly signer: SigningKey;
   protected readonly requestHandler: RequestHandler;
 
   /**
@@ -35,7 +35,7 @@ export class Node {
     private readonly storeService: IStoreService,
     nodeConfig: NodeConfig
   ) {
-    this.signer = new ethers.utils.SigningKey(privateKey);
+    this.signer = new SigningKey(privateKey);
     this.incoming = new EventEmitter();
     this.outgoing = new EventEmitter();
     this.channels = new Channels(
diff --git a/packages/node/src/utils.ts b/packages/node/src/utils.ts
index 5fb36c7d0..cc01d5198 100644
--- a/packages/node/src/utils.ts
+++ b/packages/node/src/utils.ts
@@ -1,11 +1,9 @@
 import { Address } from "@counterfactual/common-types";
-import { ethers } from "ethers";
-
-export const zeroBalance = ethers.utils.bigNumberify("0");
+import { BigNumber, hashMessage } from "ethers/utils";
 
 export function orderedAddressesHash(addresses: Address[]): string {
   addresses.sort((addrA: Address, addrB: Address) => {
-    return new ethers.utils.BigNumber(addrA).lt(addrB) ? -1 : 1;
+    return new BigNumber(addrA).lt(addrB) ? -1 : 1;
   });
-  return ethers.utils.hashMessage(addresses.join(""));
+  return hashMessage(addresses.join(""));
 }
diff --git a/packages/node/test/integration/get-app-instances.spec.ts b/packages/node/test/integration/get-app-instances.spec.ts
index 3ba17d974..ede2a4cd7 100644
--- a/packages/node/test/integration/get-app-instances.spec.ts
+++ b/packages/node/test/integration/get-app-instances.spec.ts
@@ -4,7 +4,7 @@ import {
 } from "@counterfactual/common-types";
 import cuid from "cuid";
 import dotenv from "dotenv";
-import { ethers } from "ethers";
+import { Wallet } from "ethers";
 import FirebaseServer from "firebase-server";
 
 import { IStoreService, Node, NodeConfig } from "../../src";
@@ -63,7 +63,7 @@ describe("Node method follows spec - getAppInstances", () => {
 
   it("can accept a valid call to get non-empty list of app instances", async done => {
     // the peer with whom an installation proposal is being made
-    const peerAddress = new ethers.Wallet(B_PRIVATE_KEY).address;
+    const peerAddress = new Wallet(B_PRIVATE_KEY).address;
 
     // first, a channel must be opened for it to have an app instance
     const multisigAddress = await getNewMultisig(node, [
diff --git a/packages/node/test/integration/node-communication.spec.ts b/packages/node/test/integration/node-communication.spec.ts
index 7f1311385..fc5b276e0 100644
--- a/packages/node/test/integration/node-communication.spec.ts
+++ b/packages/node/test/integration/node-communication.spec.ts
@@ -1,5 +1,5 @@
 import dotenv from "dotenv";
-import { ethers } from "ethers";
+import { AddressZero } from "ethers/constants";
 import FirebaseServer from "firebase-server";
 
 import { IMessagingService } from "../../src";
@@ -28,7 +28,7 @@ describe("Two nodes can communicate with each other", () => {
   });
 
   it("can setup listeners for events through messaging service", done => {
-    const address = ethers.constants.AddressZero;
+    const address = AddressZero;
     const testMsg = {
       event: "testEvent",
       data: {
diff --git a/packages/node/test/integration/node-store.spec.ts b/packages/node/test/integration/node-store.spec.ts
index 36bcc3d72..a524f31e1 100644
--- a/packages/node/test/integration/node-store.spec.ts
+++ b/packages/node/test/integration/node-store.spec.ts
@@ -1,9 +1,9 @@
 import dotenv from "dotenv";
-import { ethers } from "ethers";
+import { Wallet } from "ethers";
+import { AddressZero } from "ethers/constants";
 import FirebaseServer from "firebase-server";
 
 import { IStoreService, Node, NodeConfig } from "../../src";
-
 import { A_PRIVATE_KEY, B_PRIVATE_KEY } from "../env";
 import { MOCK_MESSAGING_SERVICE } from "../mock-services/mock-messaging-service";
 
@@ -42,12 +42,9 @@ describe("Node can use storage service", () => {
   });
 
   it("can save multiple channels under respective multisig indeces and query for all channels", async () => {
-    const channelA = { owners: [node.address, ethers.constants.AddressZero] };
+    const channelA = { owners: [node.address, AddressZero] };
     const channelB = {
-      owners: [
-        new ethers.Wallet(B_PRIVATE_KEY).address,
-        ethers.constants.AddressZero
-      ]
+      owners: [new Wallet(B_PRIVATE_KEY).address, AddressZero]
     };
     await storeService.set([{ key: "multisigAddress/0x111", value: channelA }]);
     await storeService.set([{ key: "multisigAddress/0x222", value: channelB }]);
@@ -62,12 +59,9 @@ describe("Node can use storage service", () => {
   });
 
   it("can save multiple channels under respective multisig indeces in one call and query for all channels", async () => {
-    const channelA = { owners: [node.address, ethers.constants.AddressZero] };
+    const channelA = { owners: [node.address, AddressZero] };
     const channelB = {
-      owners: [
-        new ethers.Wallet(B_PRIVATE_KEY).address,
-        ethers.constants.AddressZero
-      ]
+      owners: [new Wallet(B_PRIVATE_KEY).address, AddressZero]
     };
     await storeService.set([
       { key: "multisigAddress/0x111", value: channelA },
diff --git a/packages/node/test/integration/utils.ts b/packages/node/test/integration/utils.ts
index c88fdb08c..77c21da16 100644
--- a/packages/node/test/integration/utils.ts
+++ b/packages/node/test/integration/utils.ts
@@ -5,7 +5,7 @@ import {
   Node as NodeTypes
 } from "@counterfactual/common-types";
 import cuid from "cuid";
-import { ethers } from "ethers";
+import { One } from "ethers/constants";
 
 import { Node } from "../../src";
 import { APP_INSTANCE_STATUS } from "../../src/models";
@@ -95,9 +95,9 @@ export function makeProposalRequest(
     asset: {
       assetType: AssetType.ETH
     },
-    myDeposit: ethers.utils.bigNumberify("1"),
-    peerDeposit: ethers.utils.bigNumberify("1"),
-    timeout: ethers.utils.bigNumberify("1"),
+    myDeposit: One,
+    peerDeposit: One,
+    timeout: One,
     initialState: {
       propertyA: "A",
       propertyB: "B"