3 files changed, 8 insertions, 17 deletions
diff --git a/packages/assert/README.md b/packages/assert/README.md
index 598fee613..1f2139d47 100644
--- a/packages/assert/README.md
+++ b/packages/assert/README.md
@@ -46,28 +46,16 @@ yarn install
 
 ### Build
 
-If this is your **first** time building this package, you must first build **all** packages within the monorepo. This is because packages that depend on other packages located inside this monorepo are symlinked when run from **within** the monorepo. This allows you to make changes across multiple packages without first publishing dependent packages to NPM. To build all packages, run the following from the monorepo root directory:
+To build this package and all other monorepo packages that it depends on, run the following from the monorepo root directory:
 
 ```bash
-yarn lerna:rebuild
+PKG=@0xproject/assert yarn build
 ```
 
 Or continuously rebuild on change:
 
 ```bash
-yarn dev
-```
-
-You can also build this specific package by running the following from within its directory:
-
-```bash
-yarn build
-```
-
-or continuously rebuild on change:
-
-```bash
-yarn build:watch
+PKG=@0xproject/assert yarn watch
 ```
 
 ### Clean
diff --git a/packages/assert/package.json b/packages/assert/package.json
index f86bbb33f..c6d77c1bd 100644
--- a/packages/assert/package.json
+++ b/packages/assert/package.json
@@ -1,11 +1,14 @@
 {
     "name": "@0xproject/assert",
     "version": "0.2.9",
+    "engines": {
+        "node" : ">=6.12"
+    },
     "description": "Provides a standard way of performing type and schema validation across 0x projects",
     "main": "lib/src/index.js",
     "types": "lib/src/index.d.ts",
     "scripts": {
-        "build:watch": "tsc -w",
+        "watch": "tsc -w",
         "build": "tsc && copyfiles -u 3 './lib/src/monorepo_scripts/**/*' ./scripts",
         "clean": "shx rm -rf lib test_temp scripts",
         "lint": "tslint --project .",
diff --git a/packages/assert/src/index.ts b/packages/assert/src/index.ts
index 938daab92..f3b3651d5 100644
--- a/packages/assert/src/index.ts
+++ b/packages/assert/src/index.ts
@@ -10,7 +10,7 @@ export const assert = {
         const isBigNumber = _.isObject(value) && (value as any).isBigNumber;
         this.assert(isBigNumber, this.typeAssertionMessage(variableName, 'BigNumber', value));
     },
-    isValidBaseUnitAmount(variableName: string, value: BigNumber) {
+    isValidBaseUnitAmount(variableName: string, value: BigNumber): void {
         assert.isBigNumber(variableName, value);
         const isNegative = value.lessThan(0);
         this.assert(!isNegative, `${variableName} cannot be a negative number, found value: ${value.toNumber()}`);