Merge branch 'development' into removeMigrateStep

* development:
  Fix lint error
  Fix documentation links in some READMEs
  Fix relative link
  Add step to publishing that upload staging doc jsons, deploys staging website, opens every docs page and asks the dev to confirm that each one renders properly before publishing
  Fix web3Wrapper build command
  Add top-level `yarn lerna:stage_docs` to upload docJsons to the staging S3 bucket for all packages with a docs page
  Added a detailed description of `renameOverloadedMethods` (special thanks to @fabioberger). Updated Javascript styles in the Abi-Gen and Utils packages, around support for function overloading.
  Updated deployer to accept a list of contract directories as input. Contract directories are namespaced to a void clashes. Also in this commit is a fix for overloading contract functions.
  Refactor publish script to have it's main execution body be lean and discrete steps

# Conflicts:
#	packages/contracts/package.json
#	packages/deployer/package.json

38 files changed, 640 insertions, 156 deletions

diff --git a/packages/0x.js/README.md b/packages/0x.js/README.md
index 46848cbdd..cfa353504 100644
--- a/packages/0x.js/README.md
+++ b/packages/0x.js/README.md
@@ -2,7 +2,7 @@
 
 A TypeScript/Javascript library for interacting with the 0x protocol.
 
-### Read the [Documentation](0xproject.com/docs/0xjs).
+### Read the [Documentation](https://0xproject.com/docs/0xjs).
 
 ## Installation
 
diff --git a/packages/abi-gen/src/index.ts b/packages/abi-gen/src/index.ts
index 942bb12db..ecef33b16 100644
--- a/packages/abi-gen/src/index.ts
+++ b/packages/abi-gen/src/index.ts
@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 
 import { AbiDefinition, ConstructorAbi, EventAbi, MethodAbi } from '@0xproject/types';
-import { logUtils } from '@0xproject/utils';
+import { abiUtils, logUtils } from '@0xproject/utils';
 import chalk from 'chalk';
 import * as fs from 'fs';
 import { sync as globSync } from 'glob';
@@ -12,7 +12,7 @@ import * as yargs from 'yargs';
 
 import toSnakeCase = require('to-snake-case');
 
-import { ContextData, ContractsBackend, ParamKind } from './types';
+import { ContextData, ContractsBackend, Method, ParamKind } from './types';
 import { utils } from './utils';
 
 const ABI_TYPE_CONSTRUCTOR = 'constructor';
@@ -83,7 +83,6 @@ function writeOutputFile(name: string, renderedTsCode: string): void {
 
 Handlebars.registerHelper('parameterType', utils.solTypeToTsType.bind(utils, ParamKind.Input, args.backend));
 Handlebars.registerHelper('returnType', utils.solTypeToTsType.bind(utils, ParamKind.Output, args.backend));
-
 if (args.partials) {
     registerPartials(args.partials);
 }
@@ -126,11 +125,12 @@ for (const abiFileName of abiFileNames) {
     }
 
     const methodAbis = ABI.filter((abi: AbiDefinition) => abi.type === ABI_TYPE_METHOD) as MethodAbi[];
-    const methodsData = _.map(methodAbis, methodAbi => {
-        _.map(methodAbi.inputs, (input, i: number) => {
+    const sanitizedMethodAbis = abiUtils.renameOverloadedMethods(methodAbis) as MethodAbi[];
+    const methodsData = _.map(methodAbis, (methodAbi, methodAbiIndex: number) => {
+        _.forEach(methodAbi.inputs, (input, inputIndex: number) => {
             if (_.isEmpty(input.name)) {
                 // Auto-generated getters don't have parameter names
-                input.name = `index_${i}`;
+                input.name = `index_${inputIndex}`;
             }
         });
         // This will make templates simpler
@@ -138,6 +138,8 @@ for (const abiFileName of abiFileNames) {
             ...methodAbi,
             singleReturnValue: methodAbi.outputs.length === 1,
             hasReturnValue: methodAbi.outputs.length !== 0,
+            tsName: sanitizedMethodAbis[methodAbiIndex].name,
+            functionSignature: abiUtils.getFunctionSignature(methodAbi),
         };
         return methodData;
     });
diff --git a/packages/abi-gen/src/types.ts b/packages/abi-gen/src/types.ts
index df5b1feaf..648281774 100644
--- a/packages/abi-gen/src/types.ts
+++ b/packages/abi-gen/src/types.ts
@@ -5,13 +5,6 @@ export enum ParamKind {
     Output = 'output',
 }
 
-export enum AbiType {
-    Function = 'function',
-    Constructor = 'constructor',
-    Event = 'event',
-    Fallback = 'fallback',
-}
-
 export enum ContractsBackend {
     Web3 = 'web3',
     Ethers = 'ethers',
@@ -20,6 +13,8 @@ export enum ContractsBackend {
 export interface Method extends MethodAbi {
     singleReturnValue: boolean;
     hasReturnValue: boolean;
+    tsName: string;
+    functionSignature: string;
 }
 
 export interface ContextData {
diff --git a/packages/abi-gen/src/utils.ts b/packages/abi-gen/src/utils.ts
index 755fbc71a..20b734959 100644
--- a/packages/abi-gen/src/utils.ts
+++ b/packages/abi-gen/src/utils.ts
@@ -1,9 +1,9 @@
-import { ConstructorAbi, DataItem } from '@0xproject/types';
+import { AbiType, ConstructorAbi, DataItem } from '@0xproject/types';
 import * as fs from 'fs';
 import * as _ from 'lodash';
 import * as path from 'path';
 
-import { AbiType, ContractsBackend, ParamKind } from './types';
+import { ContractsBackend, ParamKind } from './types';
 
 export const utils = {
     solTypeToTsType(paramKind: ParamKind, backend: ContractsBackend, solType: string, components?: DataItem[]): string {
diff --git a/packages/base-contract/src/index.ts b/packages/base-contract/src/index.ts
index bba686f8b..bfa99fac1 100644
--- a/packages/base-contract/src/index.ts
+++ b/packages/base-contract/src/index.ts
@@ -1,13 +1,26 @@
-import { ContractAbi, DataItem, Provider, TxData, TxDataPayable } from '@0xproject/types';
-import { BigNumber } from '@0xproject/utils';
+import {
+    AbiDefinition,
+    AbiType,
+    ContractAbi,
+    DataItem,
+    MethodAbi,
+    Provider,
+    TxData,
+    TxDataPayable,
+} from '@0xproject/types';
+import { abiUtils, BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as ethersContracts from 'ethers-contracts';
 import * as _ from 'lodash';
 
 import { formatABIDataItem } from './utils';
 
+export interface EthersInterfaceByFunctionSignature {
+    [key: string]: ethersContracts.Interface;
+}
+
 export class BaseContract {
-    protected _ethersInterface: ethersContracts.Interface;
+    protected _ethersInterfacesByFunctionSignature: EthersInterfaceByFunctionSignature;
     protected _web3Wrapper: Web3Wrapper;
     public abi: ContractAbi;
     public address: string;
@@ -49,10 +62,37 @@ export class BaseContract {
         }
         return txDataWithDefaults;
     }
+    protected _lookupEthersInterface(functionSignature: string): ethersContracts.Interface {
+        const ethersInterface = this._ethersInterfacesByFunctionSignature[functionSignature];
+        if (_.isUndefined(ethersInterface)) {
+            throw new Error(`Failed to lookup method with function signature '${functionSignature}'`);
+        }
+        return ethersInterface;
+    }
+    protected _lookupAbi(functionSignature: string): MethodAbi {
+        const methodAbi = _.find(this.abi, (abiDefinition: AbiDefinition) => {
+            if (abiDefinition.type !== AbiType.Function) {
+                return false;
+            }
+            const abiFunctionSignature = abiUtils.getFunctionSignature(abiDefinition);
+            if (abiFunctionSignature === functionSignature) {
+                return true;
+            }
+            return false;
+        }) as MethodAbi;
+        return methodAbi;
+    }
     constructor(abi: ContractAbi, address: string, provider: Provider, defaults?: Partial<TxData>) {
         this._web3Wrapper = new Web3Wrapper(provider, defaults);
         this.abi = abi;
         this.address = address;
-        this._ethersInterface = new ethersContracts.Interface(abi);
+        const methodAbis = this.abi.filter(
+            (abiDefinition: AbiDefinition) => abiDefinition.type === AbiType.Function,
+        ) as MethodAbi[];
+        this._ethersInterfacesByFunctionSignature = {};
+        _.each(methodAbis, methodAbi => {
+            const functionSignature = abiUtils.getFunctionSignature(methodAbi);
+            this._ethersInterfacesByFunctionSignature[functionSignature] = new ethersContracts.Interface([methodAbi]);
+        });
     }
 }
diff --git a/packages/contract_templates/contract.handlebars b/packages/contract_templates/contract.handlebars
index 3e3f87f10..472452d74 100644
--- a/packages/contract_templates/contract.handlebars
+++ b/packages/contract_templates/contract.handlebars
@@ -41,6 +41,6 @@ export class {{contractName}}Contract extends BaseContract {
 {{/each}}
     constructor(abi: ContractAbi, address: string, provider: Provider, defaults?: Partial<TxData>) {
         super(abi, address, provider, defaults);
-        classUtils.bindAll(this, ['_ethersInterface', 'address', 'abi', '_web3Wrapper']);
+        classUtils.bindAll(this, ['_ethersInterfacesByFunctionSignature', 'address', 'abi', '_web3Wrapper']);
     }
 } // tslint:disable:max-file-line-count
diff --git a/packages/contract_templates/partials/callAsync.handlebars b/packages/contract_templates/partials/callAsync.handlebars
index 8de69203e..a6f4abdf2 100644
--- a/packages/contract_templates/partials/callAsync.handlebars
+++ b/packages/contract_templates/partials/callAsync.handlebars
@@ -5,9 +5,9 @@ async callAsync(
     defaultBlock?: BlockParam,
 ): Promise<{{> return_type outputs=outputs}}> {
     const self = this as any as {{contractName}}Contract;
-    const inputAbi = (_.find(self.abi, {name: '{{this.name}}'}) as MethodAbi).inputs;
+    const inputAbi = self._lookupAbi('{{this.functionSignature}}').inputs;
     [{{> params inputs=inputs}}] = BaseContract._formatABIDataItemList(inputAbi, [{{> params inputs=inputs}}], BaseContract._bigNumberToString.bind(self));
-    const encodedData = self._ethersInterface.functions.{{this.name}}(
+    const encodedData = self._lookupEthersInterface('{{this.functionSignature}}').functions.{{this.name}}(
         {{> params inputs=inputs}}
     ).data;
     const callDataWithDefaults = await self._applyDefaultsToTxDataAsync(
diff --git a/packages/contract_templates/partials/tx.handlebars b/packages/contract_templates/partials/tx.handlebars
index 41ba6d3f7..22fe0c597 100644
--- a/packages/contract_templates/partials/tx.handlebars
+++ b/packages/contract_templates/partials/tx.handlebars
@@ -1,4 +1,4 @@
-public {{this.name}} = {
+public {{this.tsName}} = {
     async sendTransactionAsync(
     {{> typed_params inputs=inputs}}
     {{#this.payable}}
@@ -9,17 +9,17 @@ public {{this.name}} = {
     {{/this.payable}}
     ): Promise<string> {
         const self = this as any as {{contractName}}Contract;
-        const inputAbi = (_.find(self.abi, {name: '{{this.name}}'}) as MethodAbi).inputs;
+        const inputAbi = self._lookupAbi('{{this.functionSignature}}').inputs;
         [{{> params inputs=inputs}}] = BaseContract._formatABIDataItemList(inputAbi, [{{> params inputs=inputs}}], BaseContract._bigNumberToString.bind(self));
-        const encodedData = self._ethersInterface.functions.{{this.name}}(
+        const encodedData = self._lookupEthersInterface('{{this.functionSignature}}').functions.{{this.name}}(
             {{> params inputs=inputs}}
-        ).data
+        ).data;
         const txDataWithDefaults = await self._applyDefaultsToTxDataAsync(
             {
                 ...txData,
                 data: encodedData,
             },
-            self.{{this.name}}.estimateGasAsync.bind(
+            self.{{this.tsName}}.estimateGasAsync.bind(
                 self,
                 {{> params inputs=inputs}}
             ),
@@ -32,11 +32,11 @@ public {{this.name}} = {
         txData: Partial<TxData> = {},
     ): Promise<number> {
         const self = this as any as {{contractName}}Contract;
-        const inputAbi = (_.find(self.abi, {name: '{{this.name}}'}) as MethodAbi).inputs;
+        const inputAbi = self._lookupAbi('{{this.functionSignature}}').inputs;
         [{{> params inputs=inputs}}] = BaseContract._formatABIDataItemList(inputAbi, [{{> params inputs=inputs}}], BaseContract._bigNumberToString.bind(this));
-        const encodedData = self._ethersInterface.functions.{{this.name}}(
+        const encodedData = self._lookupEthersInterface('{{this.functionSignature}}').functions.{{this.name}}(
             {{> params inputs=inputs}}
-        ).data
+        ).data;
         const txDataWithDefaults = await self._applyDefaultsToTxDataAsync(
             {
                 ...txData,
@@ -50,11 +50,11 @@ public {{this.name}} = {
     {{> typed_params inputs=inputs}}
     ): string {
         const self = this as any as {{contractName}}Contract;
-        const inputAbi = (_.find(self.abi, {name: '{{this.name}}'}) as MethodAbi).inputs;
+        const inputAbi = self._lookupAbi('{{this.functionSignature}}').inputs;
         [{{> params inputs=inputs}}] = BaseContract._formatABIDataItemList(inputAbi, [{{> params inputs=inputs}}], BaseContract._bigNumberToString.bind(self));
-        const abiEncodedTransactionData = self._ethersInterface.functions.{{this.name}}(
+        const abiEncodedTransactionData = self._lookupEthersInterface('{{this.name}}').functions.{{this.name}}(
             {{> params inputs=inputs}}
-        ).data
+        ).data;
         return abiEncodedTransactionData;
     },
     {{> callAsync}}
diff --git a/packages/contracts/package.json b/packages/contracts/package.json
index 04073f4b7..392ed8a8f 100644
--- a/packages/contracts/package.json
+++ b/packages/contracts/package.json
@@ -16,7 +16,7 @@
         "test:coverage": "SOLIDITY_COVERAGE=true run-s build run_mocha coverage:report:text coverage:report:lcov",
         "run_mocha": "mocha 'lib/test/**/*.js' --timeout 100000 --bail --exit",
         "compile:comment": "Yarn workspaces do not link binaries correctly so we need to reference them directly https://github.com/yarnpkg/yarn/issues/3846",
-        "compile": "node ../deployer/lib/src/cli.js compile --contracts ${npm_package_config_contracts} --contracts-dir src/contracts --artifacts-dir ../migrations/src/artifacts",
+        "compile": "node ../deployer/lib/src/cli.js compile --contracts ${npm_package_config_contracts} --contract-dirs src/contracts --artifacts-dir ../migrations/src/artifacts",
         "clean": "shx rm -rf ./lib",
         "generate_contract_wrappers": "node ../abi-gen/lib/index.js --abis  ${npm_package_config_abis} --template ../contract_templates/contract.handlebars --partials '../contract_templates/partials/**/*.handlebars' --output src/contract_wrappers/generated --backend ethers && prettier --write 'src/contract_wrappers/generated/**.ts'",
         "lint": "tslint --project . 'migrations/**/*.ts' 'test/**/*.ts' 'util/**/*.ts' 'deploy/**/*.ts'",
diff --git a/packages/deployer/README.md b/packages/deployer/README.md
index d8b049bdf..ef0ddd59d 100644
--- a/packages/deployer/README.md
+++ b/packages/deployer/README.md
@@ -2,7 +2,7 @@
 
 This repository contains a CLI tool that facilitates compiling and deployment of smart contracts.
 
-### Read the [Documentation](0xproject.com/docs/deployer).
+### Read the [Documentation](https://0xproject.com/docs/deployer).
 
 ## Installation
 
diff --git a/packages/deployer/package.json b/packages/deployer/package.json
index ad4ff30df..2c8ad4943 100644
--- a/packages/deployer/package.json
+++ b/packages/deployer/package.json
@@ -54,6 +54,7 @@
         "@types/semver": "^5.5.0",
         "@types/yargs": "^11.0.0",
         "chai": "^4.0.1",
+        "chai-as-promised": "^7.1.0",
         "copyfiles": "^1.2.0",
         "dirty-chai": "^2.0.1",
         "mocha": "^4.0.1",
diff --git a/packages/deployer/src/cli.ts b/packages/deployer/src/cli.ts
index f1cf56416..7b32187c4 100644
--- a/packages/deployer/src/cli.ts
+++ b/packages/deployer/src/cli.ts
@@ -11,7 +11,7 @@ import * as yargs from 'yargs';
 import { commands } from './commands';
 import { constants } from './utils/constants';
 import { consoleReporter } from './utils/error_reporter';
-import { CliOptions, CompilerOptions, DeployerOptions } from './utils/types';
+import { CliOptions, CompilerOptions, ContractDirectory, DeployerOptions } from './utils/types';
 
 const DEFAULT_OPTIMIZER_ENABLED = false;
 const DEFAULT_CONTRACTS_DIR = path.resolve('src/contracts');
@@ -27,7 +27,7 @@ const DEFAULT_CONTRACTS_LIST = '*';
  */
 async function onCompileCommandAsync(argv: CliOptions): Promise<void> {
     const opts: CompilerOptions = {
-        contractsDir: argv.contractsDir,
+        contractDirs: getContractDirectoriesFromList(argv.contractDirs),
         networkId: argv.networkId,
         optimizerEnabled: argv.shouldOptimize,
         artifactsDir: argv.artifactsDir,
@@ -45,7 +45,7 @@ async function onDeployCommandAsync(argv: CliOptions): Promise<void> {
     const web3Wrapper = new Web3Wrapper(provider);
     const networkId = await web3Wrapper.getNetworkIdAsync();
     const compilerOpts: CompilerOptions = {
-        contractsDir: argv.contractsDir,
+        contractDirs: getContractDirectoriesFromList(argv.contractDirs),
         networkId,
         optimizerEnabled: argv.shouldOptimize,
         artifactsDir: argv.artifactsDir,
@@ -69,6 +69,29 @@ async function onDeployCommandAsync(argv: CliOptions): Promise<void> {
 }
 /**
  * Creates a set of contracts to compile.
+ * @param contractDirectoriesList Comma separated list of contract directories
+ * @return Set of contract directories
+ */
+function getContractDirectoriesFromList(contractDirectoriesList: string): Set<ContractDirectory> {
+    const directories = new Set();
+    const possiblyNamespacedDirectories = contractDirectoriesList.split(',');
+    _.forEach(possiblyNamespacedDirectories, namespacedDirectory => {
+        const directoryComponents = namespacedDirectory.split(':');
+        if (directoryComponents.length === 1) {
+            const directory = { namespace: '', path: directoryComponents[0] };
+            directories.add(directory);
+        } else if (directoryComponents.length === 2) {
+            const directory = { namespace: directoryComponents[0], path: directoryComponents[1] };
+            directories.add(directory);
+        } else {
+            throw new Error(`Unable to parse contracts directory: '${namespacedDirectory}'`);
+        }
+    });
+
+    return directories;
+}
+/**
+ * Creates a set of contracts to compile.
  * @param contracts Comma separated list of contracts to compile
  */
 function getContractsSetFromList(contracts: string): Set<string> {
@@ -78,8 +101,7 @@ function getContractsSetFromList(contracts: string): Set<string> {
     }
     const contractsArray = contracts.split(',');
     _.forEach(contractsArray, contractName => {
-        const fileName = `${contractName}${constants.SOLIDITY_FILE_EXTENSION}`;
-        specifiedContracts.add(fileName);
+        specifiedContracts.add(contractName);
     });
     return specifiedContracts;
 }
@@ -104,10 +126,11 @@ function deployCommandBuilder(yargsInstance: any) {
 (() => {
     const identityCommandBuilder = _.identity;
     return yargs
-        .option('contracts-dir', {
+        .option('contract-dirs', {
             type: 'string',
             default: DEFAULT_CONTRACTS_DIR,
-            description: 'path of contracts directory to compile',
+            description:
+                "comma separated list of contract directories.\nTo avoid filename clashes, directories should be prefixed with a namespace as follows: 'namespace:/path/to/dir'.",
         })
         .option('network-id', {
             type: 'number',
diff --git a/packages/deployer/src/compiler.ts b/packages/deployer/src/compiler.ts
index ba360cb57..e3ecc6c72 100644
--- a/packages/deployer/src/compiler.ts
+++ b/packages/deployer/src/compiler.ts
@@ -1,4 +1,4 @@
-import { ContractAbi } from '@0xproject/types';
+import { AbiType, ContractAbi, MethodAbi } from '@0xproject/types';
 import { logUtils, promisify } from '@0xproject/utils';
 import * as ethUtil from 'ethereumjs-util';
 import * as fs from 'fs';
@@ -11,6 +11,8 @@ import solc = require('solc');
 
 import { binPaths } from './solc/bin_paths';
 import {
+    constructContractId,
+    constructUniqueSourceFileId,
     createDirIfDoesNotExistAsync,
     findImportIfExist,
     getContractArtifactIfExistsAsync,
@@ -23,11 +25,14 @@ import { fsWrapper } from './utils/fs_wrapper';
 import {
     CompilerOptions,
     ContractArtifact,
+    ContractDirectory,
+    ContractIdToSourceFileId,
     ContractNetworkData,
     ContractNetworks,
-    ContractSourceData,
+    ContractSourceDataByFileId,
     ContractSources,
     ContractSpecificSourceData,
+    FunctionNameToSeenCount,
 } from './utils/types';
 import { utils } from './utils/utils';
 
@@ -39,20 +44,22 @@ const SOLC_BIN_DIR = path.join(__dirname, '..', '..', 'solc_bin');
  * to artifact files.
  */
 export class Compiler {
-    private _contractsDir: string;
+    private _contractDirs: Set<ContractDirectory>;
     private _networkId: number;
     private _optimizerEnabled: boolean;
     private _artifactsDir: string;
     // This get's set in the beggining of `compileAsync` function. It's not called from a constructor, but it's the only public method of that class and could as well be.
     private _contractSources!: ContractSources;
     private _specifiedContracts: Set<string> = new Set();
-    private _contractSourceData: ContractSourceData = {};
+    private _contractSourceDataByFileId: ContractSourceDataByFileId = {};
+
     /**
      * Recursively retrieves Solidity source code from directory.
      * @param  dirPath Directory to search.
-     * @return Mapping of contract fileName to contract source.
+     * @param  contractBaseDir Base contracts directory of search tree.
+     * @return Mapping of sourceFilePath to the contract source.
      */
-    private static async _getContractSourcesAsync(dirPath: string): Promise<ContractSources> {
+    private static async _getContractSourcesAsync(dirPath: string, contractBaseDir: string): Promise<ContractSources> {
         let dirContents: string[] = [];
         try {
             dirContents = await fsWrapper.readdirAsync(dirPath);
@@ -68,14 +75,18 @@ export class Compiler {
                         encoding: 'utf8',
                     };
                     const source = await fsWrapper.readFileAsync(contentPath, opts);
-                    sources[fileName] = source;
-                    logUtils.log(`Reading ${fileName} source...`);
+                    if (!_.startsWith(contentPath, contractBaseDir)) {
+                        throw new Error(`Expected content path '${contentPath}' to begin with '${contractBaseDir}'`);
+                    }
+                    const sourceFilePath = contentPath.slice(contractBaseDir.length);
+                    sources[sourceFilePath] = source;
+                    logUtils.log(`Reading ${sourceFilePath} source...`);
                 } catch (err) {
                     logUtils.log(`Could not find file at ${contentPath}`);
                 }
             } else {
                 try {
-                    const nestedSources = await Compiler._getContractSourcesAsync(contentPath);
+                    const nestedSources = await Compiler._getContractSourcesAsync(contentPath, contractBaseDir);
                     sources = {
                         ...sources,
                         ...nestedSources,
@@ -93,7 +104,7 @@ export class Compiler {
      * @return An instance of the Compiler class.
      */
     constructor(opts: CompilerOptions) {
-        this._contractsDir = opts.contractsDir;
+        this._contractDirs = opts.contractDirs;
         this._networkId = opts.networkId;
         this._optimizerEnabled = opts.optimizerEnabled;
         this._artifactsDir = opts.artifactsDir;
@@ -105,25 +116,49 @@ export class Compiler {
     public async compileAsync(): Promise<void> {
         await createDirIfDoesNotExistAsync(this._artifactsDir);
         await createDirIfDoesNotExistAsync(SOLC_BIN_DIR);
-        this._contractSources = await Compiler._getContractSourcesAsync(this._contractsDir);
+        this._contractSources = {};
+        const contractIdToSourceFileId: ContractIdToSourceFileId = {};
+        const contractDirs = Array.from(this._contractDirs.values());
+        for (const contractDir of contractDirs) {
+            const sources = await Compiler._getContractSourcesAsync(contractDir.path, contractDir.path);
+            _.forIn(sources, (source, sourceFilePath) => {
+                const sourceFileId = constructUniqueSourceFileId(contractDir.namespace, sourceFilePath);
+                // Record the file's source and data
+                if (!_.isUndefined(this._contractSources[sourceFileId])) {
+                    throw new Error(`Found duplicate source files with ID '${sourceFileId}'`);
+                }
+                this._contractSources[sourceFileId] = source;
+                // Create a mapping between the contract id and its source file id
+                const contractId = constructContractId(contractDir.namespace, sourceFilePath);
+                if (!_.isUndefined(contractIdToSourceFileId[contractId])) {
+                    throw new Error(`Found duplicate contract with ID '${contractId}'`);
+                }
+                contractIdToSourceFileId[contractId] = sourceFileId;
+            });
+        }
         _.forIn(this._contractSources, this._setContractSpecificSourceData.bind(this));
-        const fileNames = this._specifiedContracts.has(ALL_CONTRACTS_IDENTIFIER)
-            ? _.keys(this._contractSources)
+        const specifiedContractIds = this._specifiedContracts.has(ALL_CONTRACTS_IDENTIFIER)
+            ? _.keys(contractIdToSourceFileId)
             : Array.from(this._specifiedContracts.values());
-        for (const fileName of fileNames) {
-            await this._compileContractAsync(fileName);
-        }
+        await Promise.all(
+            _.map(specifiedContractIds, async contractId =>
+                this._compileContractAsync(contractIdToSourceFileId[contractId]),
+            ),
+        );
     }
     /**
      * Compiles contract and saves artifact to artifactsDir.
-     * @param fileName Name of contract with '.sol' extension.
+     * @param sourceFileId Unique ID of the source file.
      */
-    private async _compileContractAsync(fileName: string): Promise<void> {
+    private async _compileContractAsync(sourceFileId: string): Promise<void> {
         if (_.isUndefined(this._contractSources)) {
             throw new Error('Contract sources not yet initialized');
         }
-        const contractSpecificSourceData = this._contractSourceData[fileName];
-        const currentArtifactIfExists = await getContractArtifactIfExistsAsync(this._artifactsDir, fileName);
+        if (_.isUndefined(this._contractSourceDataByFileId[sourceFileId])) {
+            throw new Error(`Contract source for ${sourceFileId} not yet initialized`);
+        }
+        const contractSpecificSourceData = this._contractSourceDataByFileId[sourceFileId];
+        const currentArtifactIfExists = await getContractArtifactIfExistsAsync(this._artifactsDir, sourceFileId);
         const sourceHash = `0x${contractSpecificSourceData.sourceHash.toString('hex')}`;
         const sourceTreeHash = `0x${contractSpecificSourceData.sourceTreeHash.toString('hex')}`;
 
@@ -162,16 +197,17 @@ export class Compiler {
         }
         const solcInstance = solc.setupMethods(requireFromString(solcjs, compilerBinFilename));
 
-        logUtils.log(`Compiling ${fileName} with Solidity v${solcVersion}...`);
-        const source = this._contractSources[fileName];
+        logUtils.log(`Compiling ${sourceFileId} with Solidity v${solcVersion}...`);
+        const source = this._contractSources[sourceFileId];
         const input = {
-            [fileName]: source,
+            [sourceFileId]: source,
         };
         const sourcesToCompile = {
             sources: input,
         };
+
         const compiled = solcInstance.compile(sourcesToCompile, Number(this._optimizerEnabled), importPath =>
-            findImportIfExist(this._contractSources, importPath),
+            findImportIfExist(this._contractSources, sourceFileId, importPath),
         );
 
         if (!_.isUndefined(compiled.errors)) {
@@ -193,11 +229,11 @@ export class Compiler {
                 });
             }
         }
-        const contractName = path.basename(fileName, constants.SOLIDITY_FILE_EXTENSION);
-        const contractIdentifier = `${fileName}:${contractName}`;
+        const contractName = path.basename(sourceFileId, constants.SOLIDITY_FILE_EXTENSION);
+        const contractIdentifier = `${sourceFileId}:${contractName}`;
         if (_.isUndefined(compiled.contracts[contractIdentifier])) {
             throw new Error(
-                `Contract ${contractName} not found in ${fileName}. Please make sure your contract has the same name as it's file name`,
+                `Contract ${contractName} not found in ${sourceFileId}. Please make sure your contract has the same name as it's file name`,
             );
         }
         const abi: ContractAbi = JSON.parse(compiled.contracts[contractIdentifier].interface);
@@ -207,6 +243,7 @@ export class Compiler {
         const sourceMapRuntime = compiled.contracts[contractIdentifier].srcmapRuntime;
         const sources = _.keys(compiled.sources);
         const updated_at = Date.now();
+
         const contractNetworkData: ContractNetworkData = {
             solc_version: solcVersion,
             keccak256: sourceHash,
@@ -243,28 +280,30 @@ export class Compiler {
         const artifactString = utils.stringifyWithFormatting(newArtifact);
         const currentArtifactPath = `${this._artifactsDir}/${contractName}.json`;
         await fsWrapper.writeFileAsync(currentArtifactPath, artifactString);
-        logUtils.log(`${fileName} artifact saved!`);
+        logUtils.log(`${sourceFileId} artifact saved!`);
     }
     /**
      * Gets contract dependendencies and keccak256 hash from source.
      * @param source Source code of contract.
+     * @param fileId FileId of the contract source file.
      * @return Object with contract dependencies and keccak256 hash of source.
      */
-    private _setContractSpecificSourceData(source: string, fileName: string): void {
-        if (!_.isUndefined(this._contractSourceData[fileName])) {
+    private _setContractSpecificSourceData(source: string, fileId: string): void {
+        if (!_.isUndefined(this._contractSourceDataByFileId[fileId])) {
             return;
         }
         const sourceHash = ethUtil.sha3(source);
         const solcVersionRange = parseSolidityVersionRange(source);
-        const dependencies = parseDependencies(source);
-        const sourceTreeHash = this._getSourceTreeHash(fileName, sourceHash, dependencies);
-        this._contractSourceData[fileName] = {
+        const dependencies = parseDependencies(source, fileId);
+        const sourceTreeHash = this._getSourceTreeHash(fileId, sourceHash, dependencies);
+        this._contractSourceDataByFileId[fileId] = {
             dependencies,
             solcVersionRange,
             sourceHash,
             sourceTreeHash,
         };
     }
+
     /**
      * Gets the source tree hash for a file and its dependencies.
      * @param fileName Name of contract file.
@@ -276,7 +315,7 @@ export class Compiler {
             const dependencySourceTreeHashes = _.map(dependencies, dependency => {
                 const source = this._contractSources[dependency];
                 this._setContractSpecificSourceData(source, dependency);
-                const sourceData = this._contractSourceData[dependency];
+                const sourceData = this._contractSourceDataByFileId[dependency];
                 return this._getSourceTreeHash(dependency, sourceData.sourceHash, sourceData.dependencies);
             });
             const sourceTreeHashesBuffer = Buffer.concat([sourceHash, ...dependencySourceTreeHashes]);
diff --git a/packages/deployer/src/utils/compiler.ts b/packages/deployer/src/utils/compiler.ts
index d5137d394..600495693 100644
--- a/packages/deployer/src/utils/compiler.ts
+++ b/packages/deployer/src/utils/compiler.ts
@@ -1,3 +1,4 @@
+import { AbiType, ContractAbi, MethodAbi } from '@0xproject/types';
 import { logUtils } from '@0xproject/utils';
 import * as _ from 'lodash';
 import * as path from 'path';
@@ -5,9 +6,49 @@ import * as solc from 'solc';
 
 import { constants } from './constants';
 import { fsWrapper } from './fs_wrapper';
-import { ContractArtifact, ContractSources } from './types';
+import { ContractArtifact, ContractSources, FunctionNameToSeenCount } from './types';
 
 /**
+ * Constructs a system-wide unique identifier for a source file.
+ * @param directoryNamespace Namespace of the source file's root contract directory.
+ * @param sourceFilePath Path to a source file, relative to contractBaseDir.
+ * @return sourceFileId A system-wide unique identifier for the source file.
+ */
+export function constructUniqueSourceFileId(directoryNamespace: string, sourceFilePath: string): string {
+    const namespacePrefix = !_.isEmpty(directoryNamespace) ? `/${directoryNamespace}` : '';
+    const sourceFilePathNoLeadingSlash = sourceFilePath.replace(/^\/+/g, '');
+    const sourceFileId = `${namespacePrefix}/${sourceFilePathNoLeadingSlash}`;
+    return sourceFileId;
+}
+/**
+ * Constructs a system-wide unique identifier for a dependency file.
+ * @param dependencyFilePath Path from a sourceFile to a dependency.
+ * @param  contractBaseDir Base contracts directory of search tree.
+ * @return sourceFileId A system-wide unique identifier for the source file.
+ */
+export function constructDependencyFileId(dependencyFilePath: string, sourceFilePath: string): string {
+    if (_.startsWith(dependencyFilePath, '/')) {
+        // Path of the form /namespace/path/to/dependency.sol
+        return dependencyFilePath;
+    } else {
+        // Dependency is relative to the source file: ./dependency.sol, ../../some/path/dependency.sol, etc.
+        // Join the two paths to construct a valid source file id: /namespace/path/to/dependency.sol
+        return path.join(path.dirname(sourceFilePath), dependencyFilePath);
+    }
+}
+/**
+ * Constructs a system-wide unique identifier for a contract.
+ * @param directoryNamespace Namespace of the source file's root contract directory.
+ * @param sourceFilePath Path to a source file, relative to contractBaseDir.
+ * @return sourceFileId A system-wide unique identifier for contract.
+ */
+export function constructContractId(directoryNamespace: string, sourceFilePath: string): string {
+    const namespacePrefix = !_.isEmpty(directoryNamespace) ? `${directoryNamespace}:` : '';
+    const sourceFileName = path.basename(sourceFilePath, constants.SOLIDITY_FILE_EXTENSION);
+    const contractId = `${namespacePrefix}${sourceFileName}`;
+    return contractId;
+}
+/**
  * Gets contract data on network or returns if an artifact does not exist.
  * @param artifactsDir Path to the artifacts directory.
  * @param fileName Name of contract file.
@@ -82,9 +123,10 @@ export function getNormalizedErrMsg(errMsg: string): string {
 /**
  * Parses the contract source code and extracts the dendencies
  * @param  source Contract source code
+ * @param sourceFilePath File path of the source code.
  * @return List of dependendencies
  */
-export function parseDependencies(source: string): string[] {
+export function parseDependencies(source: string, sourceFileId: string): string[] {
     // TODO: Use a proper parser
     const IMPORT_REGEX = /(import\s)/;
     const DEPENDENCY_PATH_REGEX = /"([^"]+)"/; // Source: https://github.com/BlockChainCompany/soljitsu/blob/master/lib/shared.js
@@ -95,8 +137,8 @@ export function parseDependencies(source: string): string[] {
             const dependencyMatch = line.match(DEPENDENCY_PATH_REGEX);
             if (!_.isNull(dependencyMatch)) {
                 const dependencyPath = dependencyMatch[1];
-                const basenName = path.basename(dependencyPath);
-                dependencies.push(basenName);
+                const dependencyId = constructDependencyFileId(dependencyPath, sourceFileId);
+                dependencies.push(dependencyId);
             }
         }
     });
@@ -107,14 +149,19 @@ export function parseDependencies(source: string): string[] {
  * Callback to resolve dependencies with `solc.compile`.
  * Throws error if contractSources not yet initialized.
  * @param  contractSources Source codes of contracts.
- * @param  importPath Path to an imported dependency.
+ * @param  sourceFileId ID of the source file.
+ * @param  importPath Path of dependency source file.
  * @return Import contents object containing source code of dependency.
  */
-export function findImportIfExist(contractSources: ContractSources, importPath: string): solc.ImportContents {
-    const fileName = path.basename(importPath);
-    const source = contractSources[fileName];
+export function findImportIfExist(
+    contractSources: ContractSources,
+    sourceFileId: string,
+    importPath: string,
+): solc.ImportContents {
+    const dependencyFileId = constructDependencyFileId(importPath, sourceFileId);
+    const source = contractSources[dependencyFileId];
     if (_.isUndefined(source)) {
-        throw new Error(`Contract source not found for ${fileName}`);
+        throw new Error(`Contract source not found for ${dependencyFileId}`);
     }
     const importContents: solc.ImportContents = {
         contents: source,
diff --git a/packages/deployer/src/utils/contract.ts b/packages/deployer/src/utils/contract.ts
index 9b7baac11..e8dd5218a 100644
--- a/packages/deployer/src/utils/contract.ts
+++ b/packages/deployer/src/utils/contract.ts
@@ -1,11 +1,9 @@
 import { schemas, SchemaValidator } from '@0xproject/json-schemas';
-import { ContractAbi, EventAbi, FunctionAbi, MethodAbi, TxData } from '@0xproject/types';
+import { AbiType, ContractAbi, EventAbi, FunctionAbi, MethodAbi, TxData } from '@0xproject/types';
 import { promisify } from '@0xproject/utils';
 import * as _ from 'lodash';
 import * as Web3 from 'web3';
 
-import { AbiType } from './types';
-
 export class Contract implements Web3.ContractInstance {
     public address: string;
     public abi: ContractAbi;
diff --git a/packages/deployer/src/utils/encoder.ts b/packages/deployer/src/utils/encoder.ts
index 4f62662e1..806efbbca 100644
--- a/packages/deployer/src/utils/encoder.ts
+++ b/packages/deployer/src/utils/encoder.ts
@@ -1,9 +1,7 @@
-import { AbiDefinition, ContractAbi, DataItem } from '@0xproject/types';
+import { AbiDefinition, AbiType, ContractAbi, DataItem } from '@0xproject/types';
 import * as _ from 'lodash';
 import * as web3Abi from 'web3-eth-abi';
 
-import { AbiType } from './types';
-
 export const encoder = {
     encodeConstructorArgsFromAbi(args: any[], abi: ContractAbi): string {
         const constructorTypes: string[] = [];
diff --git a/packages/deployer/src/utils/types.ts b/packages/deployer/src/utils/types.ts
index 7d131f5ce..1a866b873 100644
--- a/packages/deployer/src/utils/types.ts
+++ b/packages/deployer/src/utils/types.ts
@@ -18,6 +18,11 @@ export interface ContractNetworks {
     [key: number]: ContractNetworkData;
 }
 
+export interface ContractDirectory {
+    path: string;
+    namespace: string;
+}
+
 export interface ContractNetworkData {
     solc_version: string;
     optimizer_enabled: boolean;
@@ -40,7 +45,7 @@ export interface SolcErrors {
 
 export interface CliOptions extends yargs.Arguments {
     artifactsDir: string;
-    contractsDir: string;
+    contractDirs: string;
     jsonrpcUrl: string;
     networkId: number;
     shouldOptimize: boolean;
@@ -51,7 +56,7 @@ export interface CliOptions extends yargs.Arguments {
 }
 
 export interface CompilerOptions {
-    contractsDir: string;
+    contractDirs: Set<ContractDirectory>;
     networkId: number;
     optimizerEnabled: boolean;
     artifactsDir: string;
@@ -78,7 +83,11 @@ export interface ContractSources {
     [key: string]: string;
 }
 
-export interface ContractSourceData {
+export interface ContractIdToSourceFileId {
+    [key: string]: string;
+}
+
+export interface ContractSourceDataByFileId {
     [key: string]: ContractSpecificSourceData;
 }
 
@@ -98,4 +107,8 @@ export interface Token {
     swarmHash: string;
 }
 
+export interface FunctionNameToSeenCount {
+    [key: string]: number;
+}
+
 export type DoneCallback = (err?: Error) => void;
diff --git a/packages/deployer/test/compiler_test.ts b/packages/deployer/test/compiler_test.ts
index b03ae7935..817a3b3f9 100644
--- a/packages/deployer/test/compiler_test.ts
+++ b/packages/deployer/test/compiler_test.ts
@@ -3,7 +3,13 @@ import 'mocha';
 
 import { Compiler } from '../src/compiler';
 import { fsWrapper } from '../src/utils/fs_wrapper';
-import { CompilerOptions, ContractArtifact, ContractNetworkData, DoneCallback } from '../src/utils/types';
+import {
+    CompilerOptions,
+    ContractArtifact,
+    ContractDirectory,
+    ContractNetworkData,
+    DoneCallback,
+} from '../src/utils/types';
 
 import { exchange_binary } from './fixtures/exchange_bin';
 import { constants } from './util/constants';
@@ -13,11 +19,15 @@ const expect = chai.expect;
 describe('#Compiler', function() {
     this.timeout(constants.timeoutMs);
     const artifactsDir = `${__dirname}/fixtures/artifacts`;
-    const contractsDir = `${__dirname}/fixtures/contracts`;
+    const mainContractDir: ContractDirectory = { path: `${__dirname}/fixtures/contracts/main`, namespace: 'main' };
+    const baseContractDir: ContractDirectory = { path: `${__dirname}/fixtures/contracts/base`, namespace: 'base' };
+    const contractDirs: Set<ContractDirectory> = new Set();
+    contractDirs.add(mainContractDir);
+    contractDirs.add(baseContractDir);
     const exchangeArtifactPath = `${artifactsDir}/Exchange.json`;
     const compilerOpts: CompilerOptions = {
         artifactsDir,
-        contractsDir,
+        contractDirs,
         networkId: constants.networkId,
         optimizerEnabled: constants.optimizerEnabled,
         specifiedContracts: new Set(constants.specifiedContracts),
diff --git a/packages/deployer/test/compiler_utils_test.ts b/packages/deployer/test/compiler_utils_test.ts
index 246304858..5377d3308 100644
--- a/packages/deployer/test/compiler_utils_test.ts
+++ b/packages/deployer/test/compiler_utils_test.ts
@@ -47,28 +47,34 @@ describe('Compiler utils', () => {
     });
     describe('#parseDependencies', () => {
         it('correctly parses Exchange dependencies', async () => {
-            const exchangeSource = await fsWrapper.readFileAsync(`${__dirname}/fixtures/contracts/Exchange.sol`, {
+            const exchangeSource = await fsWrapper.readFileAsync(`${__dirname}/fixtures/contracts/main/Exchange.sol`, {
                 encoding: 'utf8',
             });
-            expect(parseDependencies(exchangeSource)).to.be.deep.equal([
-                'TokenTransferProxy.sol',
-                'Token.sol',
-                'SafeMath.sol',
+            const sourceFileId = '/main/Exchange.sol';
+            expect(parseDependencies(exchangeSource, sourceFileId)).to.be.deep.equal([
+                '/main/TokenTransferProxy.sol',
+                '/base/Token.sol',
+                '/base/SafeMath.sol',
             ]);
         });
         it('correctly parses TokenTransferProxy dependencies', async () => {
             const exchangeSource = await fsWrapper.readFileAsync(
-                `${__dirname}/fixtures/contracts/TokenTransferProxy.sol`,
+                `${__dirname}/fixtures/contracts/main/TokenTransferProxy.sol`,
                 {
                     encoding: 'utf8',
                 },
             );
-            expect(parseDependencies(exchangeSource)).to.be.deep.equal(['Token.sol', 'Ownable.sol']);
+            const sourceFileId = '/main/TokenTransferProxy.sol';
+            expect(parseDependencies(exchangeSource, sourceFileId)).to.be.deep.equal([
+                '/base/Token.sol',
+                '/base/Ownable.sol',
+            ]);
         });
         // TODO: For now that doesn't work. This will work after we switch to a grammar-based parser
         it.skip('correctly parses commented out dependencies', async () => {
             const contractWithCommentedOutDependencies = `// import "./TokenTransferProxy.sol";`;
-            expect(parseDependencies(contractWithCommentedOutDependencies)).to.be.deep.equal([]);
+            const sourceFileId = '/main/TokenTransferProxy.sol';
+            expect(parseDependencies(contractWithCommentedOutDependencies, sourceFileId)).to.be.deep.equal([]);
         });
     });
 });
diff --git a/packages/deployer/test/deployer_test.ts b/packages/deployer/test/deployer_test.ts
index 238624220..a213932f9 100644
--- a/packages/deployer/test/deployer_test.ts
+++ b/packages/deployer/test/deployer_test.ts
@@ -4,7 +4,13 @@ import 'mocha';
 import { Compiler } from '../src/compiler';
 import { Deployer } from '../src/deployer';
 import { fsWrapper } from '../src/utils/fs_wrapper';
-import { CompilerOptions, ContractArtifact, ContractNetworkData, DoneCallback } from '../src/utils/types';
+import {
+    CompilerOptions,
+    ContractArtifact,
+    ContractDirectory,
+    ContractNetworkData,
+    DoneCallback,
+} from '../src/utils/types';
 
 import { constructor_args, exchange_binary } from './fixtures/exchange_bin';
 import { constants } from './util/constants';
@@ -14,11 +20,15 @@ const expect = chai.expect;
 
 describe('#Deployer', () => {
     const artifactsDir = `${__dirname}/fixtures/artifacts`;
-    const contractsDir = `${__dirname}/fixtures/contracts`;
     const exchangeArtifactPath = `${artifactsDir}/Exchange.json`;
+    const mainContractDir: ContractDirectory = { path: `${__dirname}/fixtures/contracts/main`, namespace: '' };
+    const baseContractDir: ContractDirectory = { path: `${__dirname}/fixtures/contracts/base`, namespace: 'base' };
+    const contractDirs: Set<ContractDirectory> = new Set();
+    contractDirs.add(mainContractDir);
+    contractDirs.add(baseContractDir);
     const compilerOpts: CompilerOptions = {
         artifactsDir,
-        contractsDir,
+        contractDirs,
         networkId: constants.networkId,
         optimizerEnabled: constants.optimizerEnabled,
         specifiedContracts: new Set(constants.specifiedContracts),
diff --git a/packages/deployer/test/fixtures/contracts/Exchange.sol b/packages/deployer/test/fixtures/contracts/main/Exchange.sol
index 1b6819700..ea9ca3afa 100644
--- a/packages/deployer/test/fixtures/contracts/Exchange.sol
+++ b/packages/deployer/test/fixtures/contracts/main/Exchange.sol
@@ -1,6 +1,6 @@
 /*
 
-  Copyright 2017 ZeroEx Intl.
+  Copyright 2018 ZeroEx Intl.
 
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
@@ -19,8 +19,8 @@
 pragma solidity 0.4.14;
 
 import "./TokenTransferProxy.sol";
-import "./base/Token.sol";
-import "./base/SafeMath.sol";
+import "/base/Token.sol";
+import "/base/SafeMath.sol";
 
 /// @title Exchange - Facilitates exchange of ERC20 tokens.
 /// @author Amir Bandeali - <amir@0xProject.com>, Will Warren - <will@0xProject.com>
diff --git a/packages/deployer/test/fixtures/contracts/TokenTransferProxy.sol b/packages/deployer/test/fixtures/contracts/main/TokenTransferProxy.sol
index 90c8e7d66..99d16cb57 100644
--- a/packages/deployer/test/fixtures/contracts/TokenTransferProxy.sol
+++ b/packages/deployer/test/fixtures/contracts/main/TokenTransferProxy.sol
@@ -1,6 +1,6 @@
 /*
 
-  Copyright 2017 ZeroEx Intl.
+  Copyright 2018 ZeroEx Intl.
 
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
@@ -18,8 +18,8 @@
 
 pragma solidity 0.4.14;
 
-import "./base/Token.sol";
-import "./base/Ownable.sol";
+import "/base/Token.sol";
+import "/base/Ownable.sol";
 
 /// @title TokenTransferProxy - Transfers tokens on behalf of contracts that have been approved via decentralized governance.
 /// @author Amir Bandeali - <amir@0xProject.com>, Will Warren - <will@0xProject.com>
diff --git a/packages/json-schemas/README.md b/packages/json-schemas/README.md
index e8cece63b..ffa8e947a 100644
--- a/packages/json-schemas/README.md
+++ b/packages/json-schemas/README.md
@@ -2,7 +2,7 @@
 
 Contains 0x-related json schemas
 
-### Read the [Documentation](0xproject.com/docs/json-schemas).
+### Read the [Documentation](https://0xproject.com/docs/json-schemas).
 
 ## Installation
 
diff --git a/packages/metacoin/artifacts/Metacoin.json b/packages/metacoin/artifacts/Metacoin.json
index 46c3ee71c..69ec22cac 100644
--- a/packages/metacoin/artifacts/Metacoin.json
+++ b/packages/metacoin/artifacts/Metacoin.json
@@ -3,11 +3,50 @@
     "networks": {
         "50": {
             "solc_version": "0.4.21",
-            "keccak256": "0x2c3aa2e9dbef58abf57cecc148464d0852a83d7f30bbd2066f2a13b8bd3b1dd0",
-            "source_tree_hash": "0x2c3aa2e9dbef58abf57cecc148464d0852a83d7f30bbd2066f2a13b8bd3b1dd0",
+            "keccak256": "0x85fb29ea6c21adcf07f754b2ad06482dd6fcd62d31935e36041b4d064c6a038e",
+            "source_tree_hash": "0x85fb29ea6c21adcf07f754b2ad06482dd6fcd62d31935e36041b4d064c6a038e",
             "optimizer_enabled": false,
             "abi": [
                 {
+                    "constant": false,
+                    "inputs": [
+                        {
+                            "components": [
+                                {
+                                    "components": [
+                                        {
+                                            "name": "to",
+                                            "type": "address"
+                                        },
+                                        {
+                                            "name": "amount",
+                                            "type": "uint256"
+                                        }
+                                    ],
+                                    "name": "transferData",
+                                    "type": "tuple"
+                                },
+                                {
+                                    "name": "callback",
+                                    "type": "uint32"
+                                }
+                            ],
+                            "name": "nestedTransferData",
+                            "type": "tuple"
+                        }
+                    ],
+                    "name": "transfer",
+                    "outputs": [
+                        {
+                            "name": "",
+                            "type": "int256"
+                        }
+                    ],
+                    "payable": false,
+                    "stateMutability": "nonpayable",
+                    "type": "function"
+                },
+                {
                     "constant": true,
                     "inputs": [
                         {
@@ -56,6 +95,39 @@
                     "type": "function"
                 },
                 {
+                    "constant": false,
+                    "inputs": [
+                        {
+                            "components": [
+                                {
+                                    "name": "to",
+                                    "type": "address"
+                                },
+                                {
+                                    "name": "amount",
+                                    "type": "uint256"
+                                }
+                            ],
+                            "name": "transferData",
+                            "type": "tuple"
+                        },
+                        {
+                            "name": "callback",
+                            "type": "uint32"
+                        }
+                    ],
+                    "name": "transfer",
+                    "outputs": [
+                        {
+                            "name": "",
+                            "type": "int256"
+                        }
+                    ],
+                    "payable": false,
+                    "stateMutability": "nonpayable",
+                    "type": "function"
+                },
+                {
                     "inputs": [],
                     "payable": false,
                     "stateMutability": "nonpayable",
@@ -84,15 +156,14 @@
                     "type": "event"
                 }
             ],
-            "bytecode":
-                "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",
-            "runtime_bytecode":
-                "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",
-            "updated_at": 1522318279735,
-            "source_map": "60:662:0:-;;;290:72;;;;;;;;350:5;327:8;:20;336:10;327:20;;;;;;;;;;;;;;;:28;;;;60:662;;;;;;",
-            "source_map_runtime":
-                "60:662:0:-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;84:41;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;368:352;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;84:41;;;;;;;;;;;;;;;;;:::o;368:352::-;429:12;480;:19;;;457:8;:20;466:10;457:20;;;;;;;;;;;;;;;;:42;453:60;;;508:5;501:12;;;;453:60;547:12;:19;;;523:8;:20;532:10;523:20;;;;;;;;;;;;;;;;:43;;;;;;;;;;;605:12;:19;;;576:8;:25;585:12;:15;;;576:25;;;;;;;;;;;;;;;;:48;;;;;;;;;;;655:12;:15;;;634:58;;643:10;634:58;;;672:12;:19;;;634:58;;;;;;;;;;;;;;;709:4;702:11;;368:352;;;;:::o;5:118:-1:-;;72:46;110:6;97:20;72:46;;;63:55;;57:66;;;;;165:469;;282:4;270:9;265:3;261:19;257:30;254:2;;;300:1;297;290:12;254:2;318:20;333:4;318:20;;;309:29;;386:1;417:49;462:3;453:6;442:9;438:22;417:49;;;411:3;404:5;400:15;393:74;348:130;530:2;563:49;608:3;599:6;588:9;584:22;563:49;;;556:4;549:5;545:16;538:75;488:136;248:386;;;;;641:118;;708:46;746:6;733:20;708:46;;;699:55;;693:66;;;;;766:241;;870:2;858:9;849:7;845:23;841:32;838:2;;;886:1;883;876:12;838:2;921:1;938:53;983:7;974:6;963:9;959:22;938:53;;;928:63;;900:97;832:175;;;;;1014:297;;1146:2;1134:9;1125:7;1121:23;1117:32;1114:2;;;1162:1;1159;1152:12;1114:2;1197:1;1214:81;1287:7;1278:6;1267:9;1263:22;1214:81;;;1204:91;;1176:125;1108:203;;;;;1318:101;1385:28;1407:5;1385:28;;;1380:3;1373:41;1367:52;;;1426:110;1499:31;1524:5;1499:31;;;1494:3;1487:44;1481:55;;;1543:181;;1645:2;1634:9;1630:18;1622:26;;1659:55;1711:1;1700:9;1696:17;1687:6;1659:55;;;1616:108;;;;;1731:193;;1839:2;1828:9;1824:18;1816:26;;1853:61;1911:1;1900:9;1896:17;1887:6;1853:61;;;1810:114;;;;;1931:256;;1993:2;1987:9;1977:19;;2031:4;2023:6;2019:17;2130:6;2118:10;2115:22;2094:18;2082:10;2079:34;2076:62;2073:2;;;2151:1;2148;2141:12;2073:2;2171:10;2167:2;2160:22;1971:216;;;;;2194:92;;2274:5;2267:13;2260:21;2249:32;;2243:43;;;;2293:79;;2362:5;2351:16;;2345:27;;;;2379:128;;2459:42;2452:5;2448:54;2437:65;;2431:76;;;;2514:79;;2583:5;2572:16;;2566:27;;;",
-            "sources": ["Metacoin.sol"]
+            "bytecode": "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",
+            "runtime_bytecode": "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",
+            "updated_at": 1522966321930,
+            "source_map": "60:1093:0:-;;;389:72;;;;;;;;449:5;426:8;:20;435:10;426:20;;;;;;;;;;;;;;;:28;;;;60:1093;;;;;;",
+            "source_map_runtime": "60:1093:0:-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;978:172;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;84:41;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;467:352;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;825:147;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;978:172;1051:3;1073:70;1082:18;:31;;;1115:18;:27;;;1073:8;:70::i;:::-;1066:77;;978:172;;;:::o;84:41::-;;;;;;;;;;;;;;;;;:::o;467:352::-;528:12;579;:19;;;556:8;:20;565:10;556:20;;;;;;;;;;;;;;;;:42;552:60;;;607:5;600:12;;;;552:60;646:12;:19;;;622:8;:20;631:10;622:20;;;;;;;;;;;;;;;;:43;;;;;;;;;;;704:12;:19;;;675:8;:25;684:12;:15;;;675:25;;;;;;;;;;;;;;;;:48;;;;;;;;;;;754:12;:15;;;733:58;;742:10;733:58;;;771:12;:19;;;733:58;;;;;;;;;;;;;;;808:4;801:11;;467:352;;;;:::o;825:147::-;903:3;918:22;927:12;918:8;:22::i;:::-;;957:8;950:15;;;;825:147;;;;:::o;5:118:-1:-;;72:46;110:6;97:20;72:46;;;63:55;;57:66;;;;;171:510;;294:4;282:9;277:3;273:19;269:30;266:2;;;312:1;309;302:12;266:2;330:20;345:4;330:20;;;321:29;;408:1;439:73;508:3;499:6;488:9;484:22;439:73;;;433:3;426:5;422:15;415:98;360:164;578:2;611:48;655:3;646:6;635:9;631:22;611:48;;;604:4;597:5;593:16;586:74;534:137;260:421;;;;;723:465;;836:4;824:9;819:3;815:19;811:30;808:2;;;854:1;851;844:12;808:2;872:20;887:4;872:20;;;863:29;;940:1;971:49;1016:3;1007:6;996:9;992:22;971:49;;;965:3;958:5;954:15;947:74;902:130;1084:2;1117:49;1162:3;1153:6;1142:9;1138:22;1117:49;;;1110:4;1103:5;1099:16;1092:75;1042:136;802:386;;;;;1230:469;;1347:4;1335:9;1330:3;1326:19;1322:30;1319:2;;;1365:1;1362;1355:12;1319:2;1383:20;1398:4;1383:20;;;1374:29;;1451:1;1482:49;1527:3;1518:6;1507:9;1503:22;1482:49;;;1476:3;1469:5;1465:15;1458:74;1413:130;1595:2;1628:49;1673:3;1664:6;1653:9;1649:22;1628:49;;;1621:4;1614:5;1610:16;1603:75;1553:136;1313:386;;;;;1706:118;;1773:46;1811:6;1798:20;1773:46;;;1764:55;;1758:66;;;;;1831:116;;1897:45;1934:6;1921:20;1897:45;;;1888:54;;1882:65;;;;;1954:241;;2058:2;2046:9;2037:7;2033:23;2029:32;2026:2;;;2074:1;2071;2064:12;2026:2;2109:1;2126:53;2171:7;2162:6;2151:9;2147:22;2126:53;;;2116:63;;2088:97;2020:175;;;;;2202:309;;2340:2;2328:9;2319:7;2315:23;2311:32;2308:2;;;2356:1;2353;2346:12;2308:2;2391:1;2408:87;2487:7;2478:6;2467:9;2463:22;2408:87;;;2398:97;;2370:131;2302:209;;;;;2518:297;;2650:2;2638:9;2629:7;2625:23;2621:32;2618:2;;;2666:1;2663;2656:12;2618:2;2701:1;2718:81;2791:7;2782:6;2771:9;2767:22;2718:81;;;2708:91;;2680:125;2612:203;;;;;2822:420;;;2970:2;2958:9;2949:7;2945:23;2941:32;2938:2;;;2986:1;2983;2976:12;2938:2;3021:1;3038:81;3111:7;3102:6;3091:9;3087:22;3038:81;;;3028:91;;3000:125;3156:2;3174:52;3218:7;3209:6;3198:9;3194:22;3174:52;;;3164:62;;3135:97;2932:310;;;;;;3249:101;3316:28;3338:5;3316:28;;;3311:3;3304:41;3298:52;;;3357:107;3428:30;3452:5;3428:30;;;3423:3;3416:43;3410:54;;;3471:110;3544:31;3569:5;3544:31;;;3539:3;3532:44;3526:55;;;3588:181;;3690:2;3679:9;3675:18;3667:26;;3704:55;3756:1;3745:9;3741:17;3732:6;3704:55;;;3661:108;;;;;3776:189;;3882:2;3871:9;3867:18;3859:26;;3896:59;3952:1;3941:9;3937:17;3928:6;3896:59;;;3853:112;;;;;3972:193;;4080:2;4069:9;4065:18;4057:26;;4094:61;4152:1;4141:9;4137:17;4128:6;4094:61;;;4051:114;;;;;4172:256;;4234:2;4228:9;4218:19;;4272:4;4264:6;4260:17;4371:6;4359:10;4356:22;4335:18;4323:10;4320:34;4317:62;4314:2;;;4392:1;4389;4382:12;4314:2;4412:10;4408:2;4401:22;4212:216;;;;;4435:92;;4515:5;4508:13;4501:21;4490:32;;4484:43;;;;4534:78;;4602:5;4591:16;;4585:27;;;;4619:79;;4688:5;4677:16;;4671:27;;;;4705:128;;4785:42;4778:5;4774:54;4763:65;;4757:76;;;;4840:79;;4909:5;4898:16;;4892:27;;;;4926:95;;5005:10;4998:5;4994:22;4983:33;;4977:44;;;",
+            "sources": [
+                "/Metacoin.sol"
+            ]
         }
     }
-}
+}
\ No newline at end of file
diff --git a/packages/metacoin/contracts/Metacoin.sol b/packages/metacoin/contracts/Metacoin.sol
index 6b6814b21..ac212b32e 100644
--- a/packages/metacoin/contracts/Metacoin.sol
+++ b/packages/metacoin/contracts/Metacoin.sol
@@ -11,6 +11,11 @@ contract Metacoin {
         uint256 amount;
     }
 
+    struct NestedTransferData {
+        TransferData transferData;
+        uint32 callback;
+    }
+
     function Metacoin() public {
         balances[msg.sender] = 10000;
     }
@@ -22,4 +27,14 @@ contract Metacoin {
         Transfer(msg.sender, transferData.to, transferData.amount);
         return true;
     }
+
+    function transfer(TransferData transferData, uint32 callback) public returns (int) {
+        transfer(transferData);
+        return callback;
+    }
+
+    function transfer(NestedTransferData nestedTransferData) public returns (int) {
+        return transfer(nestedTransferData.transferData, nestedTransferData.callback);
+    }
+
 }
diff --git a/packages/metacoin/package.json b/packages/metacoin/package.json
index f63e1df61..8795be633 100644
--- a/packages/metacoin/package.json
+++ b/packages/metacoin/package.json
@@ -18,7 +18,7 @@
         "coverage:report:html": "istanbul report html && open coverage/index.html",
         "coverage:report:lcov": "istanbul report lcov",
         "test:circleci": "yarn test:coverage",
-        "compile": "node ../deployer/lib/src/cli.js compile --contracts Metacoin --contracts-dir contracts --artifacts-dir artifacts"
+        "compile": "node ../deployer/lib/src/cli.js compile --contracts Metacoin --contract-dirs contracts --artifacts-dir artifacts"
     },
     "author": "",
     "license": "Apache-2.0",
diff --git a/packages/metacoin/test/metacoin_test.ts b/packages/metacoin/test/metacoin_test.ts
index 73537d342..51830d1ef 100644
--- a/packages/metacoin/test/metacoin_test.ts
+++ b/packages/metacoin/test/metacoin_test.ts
@@ -36,12 +36,12 @@ describe('Metacoin', () => {
         });
     });
     describe('#transfer', () => {
-        it(`should successfully transfer tokens`, async () => {
+        it(`should successfully transfer tokens (via transfer1)`, async () => {
             const ZERO_ADDRESS = '0x0000000000000000000000000000000000000000';
             const amount = INITIAL_BALANCE.div(2);
             const oldBalance = await metacoin.balances.callAsync(ZERO_ADDRESS);
             expect(oldBalance).to.be.bignumber.equal(0);
-            const txHash = await metacoin.transfer.sendTransactionAsync(
+            const txHash = await metacoin.transfer1.sendTransactionAsync(
                 {
                     to: ZERO_ADDRESS,
                     amount,
@@ -58,5 +58,57 @@ describe('Metacoin', () => {
             const newBalance = await metacoin.balances.callAsync(ZERO_ADDRESS);
             expect(newBalance).to.be.bignumber.equal(amount);
         });
+
+        it(`should successfully transfer tokens (via transfer2)`, async () => {
+            const ZERO_ADDRESS = '0x0000000000000000000000000000000000000000';
+            const amount = INITIAL_BALANCE.div(2);
+            const oldBalance = await metacoin.balances.callAsync(ZERO_ADDRESS);
+            expect(oldBalance).to.be.bignumber.equal(0);
+            const callback = 59;
+            const txHash = await metacoin.transfer2.sendTransactionAsync(
+                {
+                    to: ZERO_ADDRESS,
+                    amount,
+                },
+                callback,
+                { from: devConstants.TESTRPC_FIRST_ADDRESS },
+            );
+            const txReceipt = await web3Wrapper.awaitTransactionMinedAsync(txHash);
+            const transferLogs = txReceipt.logs[0] as LogWithDecodedArgs<TransferContractEventArgs>;
+            expect(transferLogs.args).to.be.deep.equal({
+                _to: ZERO_ADDRESS,
+                _from: devConstants.TESTRPC_FIRST_ADDRESS,
+                _value: amount,
+            });
+            const newBalance = await metacoin.balances.callAsync(ZERO_ADDRESS);
+            expect(newBalance).to.be.bignumber.equal(amount);
+        });
+
+        it(`should successfully transfer tokens (via transfer3)`, async () => {
+            const ZERO_ADDRESS = '0x0000000000000000000000000000000000000000';
+            const amount = INITIAL_BALANCE.div(2);
+            const oldBalance = await metacoin.balances.callAsync(ZERO_ADDRESS);
+            expect(oldBalance).to.be.bignumber.equal(0);
+            const callback = 59;
+            const txHash = await metacoin.transfer3.sendTransactionAsync(
+                {
+                    transferData: {
+                        to: ZERO_ADDRESS,
+                        amount,
+                    },
+                    callback,
+                },
+                { from: devConstants.TESTRPC_FIRST_ADDRESS },
+            );
+            const txReceipt = await web3Wrapper.awaitTransactionMinedAsync(txHash);
+            const transferLogs = txReceipt.logs[0] as LogWithDecodedArgs<TransferContractEventArgs>;
+            expect(transferLogs.args).to.be.deep.equal({
+                _to: ZERO_ADDRESS,
+                _from: devConstants.TESTRPC_FIRST_ADDRESS,
+                _value: amount,
+            });
+            const newBalance = await metacoin.balances.callAsync(ZERO_ADDRESS);
+            expect(newBalance).to.be.bignumber.equal(amount);
+        });
     });
 });
diff --git a/packages/monorepo-scripts/package.json b/packages/monorepo-scripts/package.json
index b113b4b39..5c0e5a411 100644
--- a/packages/monorepo-scripts/package.json
+++ b/packages/monorepo-scripts/package.json
@@ -29,6 +29,7 @@
         "@0xproject/tslint-config": "0.4.13",
         "@types/glob": "^5.0.33",
         "@types/node": "^8.0.53",
+        "@types/opn": "^5.1.0",
         "@types/rimraf": "^2.0.2",
         "depcheck": "^0.6.9",
         "lerna-get-packages": "^1.0.0",
@@ -45,7 +46,9 @@
         "glob": "^7.1.2",
         "lodash": "^4.17.4",
         "moment": "2.21.0",
+        "opn": "^5.3.0",
         "promisify-child-process": "^1.0.5",
+        "prompt": "^1.0.0",
         "publish-release": "0xproject/publish-release",
         "rimraf": "^2.6.2",
         "semver-diff": "^2.1.0",
diff --git a/packages/monorepo-scripts/src/constants.ts b/packages/monorepo-scripts/src/constants.ts
index 74387a159..081a49332 100644
--- a/packages/monorepo-scripts/src/constants.ts
+++ b/packages/monorepo-scripts/src/constants.ts
@@ -2,4 +2,5 @@ import * as path from 'path';
 
 export const constants = {
     monorepoRootPath: path.join(__dirname, '../../..'),
+    stagingWebsite: 'http://staging-0xproject.s3-website-us-east-1.amazonaws.com',
 };
diff --git a/packages/monorepo-scripts/src/globals.d.ts b/packages/monorepo-scripts/src/globals.d.ts
index c5898d0f5..1693a6dbb 100644
--- a/packages/monorepo-scripts/src/globals.d.ts
+++ b/packages/monorepo-scripts/src/globals.d.ts
@@ -3,6 +3,11 @@ declare module 'publish-release';
 declare module 'es6-promisify';
 declare module 'semver-diff';
 
+declare module 'prompt' {
+    const start: () => void;
+    const get: (promptMessages: string[], callback: (err: Error, result: string) => void) => void;
+}
+
 // semver-sort declarations
 declare module 'semver-sort' {
     const desc: (versions: string[]) => string[];
@@ -15,6 +20,7 @@ declare interface LernaPackage {
         version: string;
         name: string;
         main?: string;
+        scripts?: { [command: string]: string };
         config?: {
             additionalTsTypings?: string[];
         };
diff --git a/packages/monorepo-scripts/src/publish.ts b/packages/monorepo-scripts/src/publish.ts
index adc1de64a..21c8b72c9 100644
--- a/packages/monorepo-scripts/src/publish.ts
+++ b/packages/monorepo-scripts/src/publish.ts
@@ -1,18 +1,23 @@
 #!/usr/bin/env node
 
+import * as promisify from 'es6-promisify';
 import * as fs from 'fs';
 import lernaGetPackages = require('lerna-get-packages');
 import * as _ from 'lodash';
 import * as moment from 'moment';
+import opn = require('opn');
 import * as path from 'path';
 import { exec as execAsync, spawn } from 'promisify-child-process';
+import * as prompt from 'prompt';
 import semverDiff = require('semver-diff');
 import semverSort = require('semver-sort');
 
 import { constants } from './constants';
-import { Changelog, Changes, SemVerIndex, UpdatedPackage } from './types';
+import { Changelog, Changes, PackageToVersionChange, SemVerIndex, UpdatedPackage } from './types';
 import { utils } from './utils';
 
+const DOC_GEN_COMMAND = 'docs:json';
+const NPM_NAMESPACE = '@0xproject/';
 const IS_DRY_RUN = process.env.IS_DRY_RUN === 'true';
 const TODAYS_TIMESTAMP = moment().unix();
 const LERNA_EXECUTABLE = './node_modules/lerna/bin/lerna.js';
@@ -21,8 +26,95 @@ const semverNameToIndex: { [semver: string]: number } = {
     minor: SemVerIndex.Minor,
     major: SemVerIndex.Major,
 };
+const packageNameToWebsitePath: { [name: string]: string } = {
+    '0x.js': '0xjs',
+    'web3-wrapper': 'web3_wrapper',
+    contracts: 'contracts',
+    connect: 'connect',
+    'json-schemas': 'json-schemas',
+    deployer: 'deployer',
+    'sol-cov': 'sol-cov',
+    subproviders: 'subproviders',
+};
 
 (async () => {
+    // Fetch public, updated Lerna packages
+    const updatedPublicLernaPackages = await getUpdatedPublicLernaPackagesAsync();
+
+    await confirmDocPagesRenderAsync(updatedPublicLernaPackages);
+
+    // Update CHANGELOGs
+    const updatedPublicLernaPackageNames = _.map(updatedPublicLernaPackages, pkg => pkg.package.name);
+    utils.log(`Will update CHANGELOGs and publish: \n${updatedPublicLernaPackageNames.join('\n')}\n`);
+    const packageToVersionChange = await updateChangeLogsAsync(updatedPublicLernaPackages);
+
+    // Push changelog changes to Github
+    if (!IS_DRY_RUN) {
+        await pushChangelogsToGithubAsync();
+    }
+
+    // Call LernaPublish
+    utils.log('Version updates to apply:');
+    _.each(packageToVersionChange, (versionChange: string, packageName: string) => {
+        utils.log(`${packageName} -> ${versionChange}`);
+    });
+    utils.log(`Calling 'lerna publish'...`);
+    await lernaPublishAsync(packageToVersionChange);
+})().catch(err => {
+    utils.log(err);
+    process.exit(1);
+});
+
+async function confirmDocPagesRenderAsync(packages: LernaPackage[]) {
+    // push docs to staging
+    utils.log("Upload all docJson's to S3 staging...");
+    await execAsync(`yarn lerna:stage_docs`, { cwd: constants.monorepoRootPath });
+
+    // deploy website to staging
+    utils.log('Deploy website to staging...');
+    const pathToWebsite = `${constants.monorepoRootPath}/packages/website`;
+    await execAsync(`yarn deploy_staging`, { cwd: pathToWebsite });
+
+    const packagesWithDocs = _.filter(packages, pkg => {
+        const scriptsIfExists = pkg.package.scripts;
+        if (_.isUndefined(scriptsIfExists)) {
+            throw new Error('Found a public package without any scripts in package.json');
+        }
+        return !_.isUndefined(scriptsIfExists[DOC_GEN_COMMAND]);
+    });
+    _.each(packagesWithDocs, pkg => {
+        const name = pkg.package.name;
+        const nameWithoutPrefix = _.startsWith(name, NPM_NAMESPACE) ? name.split('@0xproject/')[1] : name;
+        const docSegmentIfExists = packageNameToWebsitePath[nameWithoutPrefix];
+        if (_.isUndefined(docSegmentIfExists)) {
+            throw new Error(
+                `Found package '${name}' with doc commands but no corresponding docSegment in monorepo_scripts
+package.ts. Please add an entry for it and try again.`,
+            );
+        }
+        const link = `${constants.stagingWebsite}/docs/${docSegmentIfExists}`;
+        // tslint:disable-next-line:no-floating-promises
+        opn(link);
+    });
+
+    prompt.start();
+    const message = 'Do all the doc pages render properly? (yn)';
+    const result = await promisify(prompt.get)([message]);
+    const didConfirm = result[message] === 'y';
+    if (!didConfirm) {
+        utils.log('Publish process aborted.');
+        process.exit(0);
+    }
+}
+
+async function pushChangelogsToGithubAsync() {
+    await execAsync(`git add . --all`, { cwd: constants.monorepoRootPath });
+    await execAsync(`git commit -m "Updated CHANGELOGS"`, { cwd: constants.monorepoRootPath });
+    await execAsync(`git push`, { cwd: constants.monorepoRootPath });
+    utils.log(`Pushed CHANGELOG updates to Github`);
+}
+
+async function getUpdatedPublicLernaPackagesAsync(): Promise<LernaPackage[]> {
     const updatedPublicPackages = await getPublicLernaUpdatedPackagesAsync();
     const updatedPackageNames = _.map(updatedPublicPackages, pkg => pkg.name);
 
@@ -30,10 +122,11 @@ const semverNameToIndex: { [semver: string]: number } = {
     const updatedPublicLernaPackages = _.filter(allLernaPackages, pkg => {
         return _.includes(updatedPackageNames, pkg.package.name);
     });
-    const updatedPublicLernaPackageNames = _.map(updatedPublicLernaPackages, pkg => pkg.package.name);
-    utils.log(`Will update CHANGELOGs and publish: \n${updatedPublicLernaPackageNames.join('\n')}\n`);
+    return updatedPublicLernaPackages;
+}
 
-    const packageToVersionChange: { [name: string]: string } = {};
+async function updateChangeLogsAsync(updatedPublicLernaPackages: LernaPackage[]): Promise<PackageToVersionChange> {
+    const packageToVersionChange: PackageToVersionChange = {};
     for (const lernaPackage of updatedPublicLernaPackages) {
         const packageName = lernaPackage.package.name;
         const changelogJSONPath = path.join(lernaPackage.location, 'CHANGELOG.json');
@@ -88,23 +181,8 @@ const semverNameToIndex: { [semver: string]: number } = {
         utils.log(`${packageName}: Updated CHANGELOG.md`);
     }
 
-    if (!IS_DRY_RUN) {
-        await execAsync(`git add . --all`, { cwd: constants.monorepoRootPath });
-        await execAsync(`git commit -m "Updated CHANGELOGS"`, { cwd: constants.monorepoRootPath });
-        await execAsync(`git push`, { cwd: constants.monorepoRootPath });
-        utils.log(`Pushed CHANGELOG updates to Github`);
-    }
-
-    utils.log('Version updates to apply:');
-    _.each(packageToVersionChange, (versionChange: string, packageName: string) => {
-        utils.log(`${packageName} -> ${versionChange}`);
-    });
-    utils.log(`Calling 'lerna publish'...`);
-    await lernaPublishAsync(packageToVersionChange);
-})().catch(err => {
-    utils.log(err);
-    process.exit(1);
-});
+    return packageToVersionChange;
+}
 
 async function lernaPublishAsync(packageToVersionChange: { [name: string]: string }) {
     // HACK: Lerna publish does not provide a way to specify multiple package versions via
diff --git a/packages/monorepo-scripts/src/types.ts b/packages/monorepo-scripts/src/types.ts
index 9e6edd186..28d00d710 100644
--- a/packages/monorepo-scripts/src/types.ts
+++ b/packages/monorepo-scripts/src/types.ts
@@ -21,3 +21,7 @@ export enum SemVerIndex {
     Minor,
     Major,
 }
+
+export interface PackageToVersionChange {
+    [name: string]: string;
+}
diff --git a/packages/sol-cov/README.md b/packages/sol-cov/README.md
index 8cc7dca6c..3a0377521 100644
--- a/packages/sol-cov/README.md
+++ b/packages/sol-cov/README.md
@@ -2,7 +2,7 @@
 
 A Solidity code coverage tool.
 
-### Read the [Documentation](0xproject.com/docs/sol-cov).
+### Read the [Documentation](https://0xproject.com/docs/sol-cov).
 
 ## Installation
 
diff --git a/packages/subproviders/README.md b/packages/subproviders/README.md
index 2936be545..8c8807895 100644
--- a/packages/subproviders/README.md
+++ b/packages/subproviders/README.md
@@ -4,7 +4,7 @@ A few useful web3 subproviders including a LedgerSubprovider useful for adding L
 
 We have written up a [Wiki](https://0xproject.com/wiki#Web3-Provider-Examples) article detailing some use cases of this subprovider package.
 
-### Read the [Documentation](0xproject.com/docs/subproviders).
+### Read the [Documentation](https://0xproject.com/docs/subproviders).
 
 ## Installation
 
diff --git a/packages/utils/src/abi_utils.ts b/packages/utils/src/abi_utils.ts
new file mode 100644
index 000000000..c4533d42e
--- /dev/null
+++ b/packages/utils/src/abi_utils.ts
@@ -0,0 +1,71 @@
+import { AbiDefinition, AbiType, ConstructorAbi, ContractAbi, DataItem, MethodAbi } from '@0xproject/types';
+import * as _ from 'lodash';
+
+export const abiUtils = {
+    parseFunctionParam(param: DataItem): string {
+        if (param.type === 'tuple') {
+            // Parse out tuple types into {type_1, type_2, ..., type_N}
+            const tupleComponents = param.components;
+            const paramString = _.map(tupleComponents, component => this.parseFunctionParam(component));
+            const tupleParamString = `{${paramString}}`;
+            return tupleParamString;
+        }
+        return param.type;
+    },
+    getFunctionSignature(methodAbi: MethodAbi): string {
+        const functionName = methodAbi.name;
+        const parameterTypeList = _.map(methodAbi.inputs, (param: DataItem) => this.parseFunctionParam(param));
+        const functionSignature = `${functionName}(${parameterTypeList})`;
+        return functionSignature;
+    },
+    /**
+     * Solidity supports function overloading whereas TypeScript does not.
+     * See: https://solidity.readthedocs.io/en/v0.4.21/contracts.html?highlight=overload#function-overloading
+     * In order to support overloaded functions, we suffix overloaded function names with an index.
+     * This index should be deterministic, regardless of function ordering within the smart contract. To do so,
+     * we assign indexes based on the alphabetical order of function signatures.
+     *
+     * E.g
+     * ['f(uint)', 'f(uint,byte32)']
+     * Should always be renamed to:
+     * ['f1(uint)', 'f2(uint,byte32)']
+     * Regardless of the order in which these these overloaded functions are declared within the contract ABI.
+     */
+    renameOverloadedMethods(inputContractAbi: ContractAbi): ContractAbi {
+        const contractAbi = _.cloneDeep(inputContractAbi);
+        const methodAbis = contractAbi.filter((abi: AbiDefinition) => abi.type === AbiType.Function) as MethodAbi[];
+        // Sort method Abis into alphabetical order, by function signature
+        const methodAbisOrdered = _.sortBy(methodAbis, [
+            (methodAbi: MethodAbi) => {
+                const functionSignature = this.getFunctionSignature(methodAbi);
+                return functionSignature;
+            },
+        ]);
+        // Group method Abis by name (overloaded methods will be grouped together, in alphabetical order)
+        const methodAbisByName: { [key: string]: MethodAbi[] } = {};
+        _.each(methodAbisOrdered, methodAbi => {
+            (methodAbisByName[methodAbi.name] || (methodAbisByName[methodAbi.name] = [])).push(methodAbi);
+        });
+        // Rename overloaded methods to overloadedMethodName1, overloadedMethodName2, ...
+        _.each(methodAbisByName, methodAbisWithSameName => {
+            _.each(methodAbisWithSameName, (methodAbi, i: number) => {
+                if (methodAbisWithSameName.length > 1) {
+                    const overloadedMethodId = i + 1;
+                    const sanitizedMethodName = `${methodAbi.name}${overloadedMethodId}`;
+                    const indexOfExistingAbiWithSanitizedMethodNameIfExists = _.findIndex(
+                        methodAbis,
+                        currentMethodAbi => currentMethodAbi.name === sanitizedMethodName,
+                    );
+                    if (indexOfExistingAbiWithSanitizedMethodNameIfExists >= 0) {
+                        const methodName = methodAbi.name;
+                        throw new Error(
+                            `Failed to rename overloaded method '${methodName}' to '${sanitizedMethodName}'. A method with this name already exists.`,
+                        );
+                    }
+                    methodAbi.name = sanitizedMethodName;
+                }
+            });
+        });
+        return contractAbi;
+    },
+};
diff --git a/packages/utils/src/index.ts b/packages/utils/src/index.ts
index debcce746..0da4b265d 100644
--- a/packages/utils/src/index.ts
+++ b/packages/utils/src/index.ts
@@ -5,3 +5,4 @@ export { intervalUtils } from './interval_utils';
 export { BigNumber } from './configured_bignumber';
 export { AbiDecoder } from './abi_decoder';
 export { logUtils } from './log_utils';
+export { abiUtils } from './abi_utils';
diff --git a/packages/web3-wrapper/README.md b/packages/web3-wrapper/README.md
index 1ff85420a..a38f49e6e 100644
--- a/packages/web3-wrapper/README.md
+++ b/packages/web3-wrapper/README.md
@@ -2,7 +2,7 @@
 
 Wrapped version of web3 with a nicer interface that is used across 0x projects and packages.
 
-### Read the [Documentation](0xproject.com/docs/web3_wrapper).
+### Read the [Documentation](https://0xproject.com/docs/web3_wrapper).
 
 ## Installation
 
diff --git a/packages/web3-wrapper/package.json b/packages/web3-wrapper/package.json
index 910d4725e..5b5f42434 100644
--- a/packages/web3-wrapper/package.json
+++ b/packages/web3-wrapper/package.json
@@ -6,7 +6,7 @@
     "types": "lib/src/index.d.ts",
     "scripts": {
         "build:watch": "tsc -w",
-        "build": "tsc && copyfiles -u 2 './lib/monorepo_scripts/**/*' ./scripts",
+        "build": "tsc && copyfiles -u 3 './lib/src/monorepo_scripts/**/*' ./scripts",
         "clean": "shx rm -rf lib scripts",
         "lint": "tslint --project . 'src/**/*.ts'",
         "test": "run-s clean build run_mocha",