diff --git a/README.md b/README.md
index 007191d..2c0ee66 100644
--- a/README.md
+++ b/README.md
@@ -11,16 +11,20 @@ npm install --save-dev webpack-config-plugin
 
 ```js
 // webpack.config.js
-var path = require("path")
-var ConfigPlugin = require("webpack-config-plugin")
+var path = require('path');
+var ConfigPlugin = require('webpack-config-plugin');
 
 module.exports = {
   // [...]
   plugins: [
     // [...]
     new ConfigPlugin({
-      // Configuration directory
-      dir: path.join(__dirname, "config")
+
+      // Configuration directory (required)
+      dir: path.join(__dirname, 'config'),
+
+      // Filter expression(s) (optional)
+      filter: [ '-secret.property' ]
     })
   ]
 }
@@ -31,3 +35,6 @@ module.exports = {
 When the plugin has been configured it enables a faux-module `config` which
 is a merge between a default configuration, an environment-specific
 configuration, and a local configuration.
+
+Please see [json-property-filter](https://www.npmjs.com/package/json-property-filter)
+for documentation of filter expressions.
diff --git a/lib/config-loader.js b/lib/config-loader.js
index 4050df9..a819e15 100644
--- a/lib/config-loader.js
+++ b/lib/config-loader.js
@@ -1,4 +1,14 @@
-module.exports = function() {
-  var config = JSON.parse(this.query.slice(1))
-  return "module.exports = " + JSON.stringify(config)
-}
+const { JsonPropertyFilter } = require('json-property-filter');
+
+module.exports = function () {
+  const { config, filter = [] } = JSON.parse(this.query.slice(1));
+
+  if (Array.isArray(filter) && filter.length > 0) {
+    const propertyFilter = new JsonPropertyFilter(filter);
+    const filteredOutput = propertyFilter.apply(config);
+
+    return `module.exports = ${JSON.stringify(filteredOutput)}`;
+  }
+
+  return `module.exports = ${JSON.stringify(config)}`;
+};
diff --git a/lib/config-plugin.js b/lib/config-plugin.js
index 08f2d71..24b2c58 100644
--- a/lib/config-plugin.js
+++ b/lib/config-plugin.js
@@ -1,76 +1,103 @@
-var _ = require("lodash")
-var path = require("path")
-
-// Load configuration file
-function loadFile(dir, filename) {
-  if (filename == null) return {}
-  filename = path.join(dir, filename)
-  try {
-    return require(filename)
-  } catch(e) {
-    return {}
+const assert = require('assert');
+const path = require('path');
+const merge = require('lodash/merge');
+
+class Config {
+
+  // Load configuration file.
+  // Fails gracefully by returning an empty object.
+  static loadConfigFile(dir, filename) {
+    if (!filename) {
+      return {};
+    }
+
+    try {
+      const pathname = path.resolve(dir, filename);
+
+      return require(pathname);
+    } catch (error) {
+      return {};
+    }
   }
-}
 
-module.exports = Config
-function Config(options) {
-  this.options = options
-  this._config = null
+  constructor(options = {}) {
+    assert(typeof options.dir === 'string', 'WebpackConfigPlugin: "options.dir" must be provided');
+    assert(!options.filter || Array.isArray(options.filter), 'WebpackConfigPlugin: "options.filter" must be an array. See "json-property-filter" package for more details');
+
+    this.options = options;
+    this.config = null;
 
-  if (this.options.environment == null) {
-    this.options.environment = process.env.NODE_ENV || "development"
+    if (!this.options.environment) {
+      this.options.environment = process.env.NODE_ENV || 'development';
+    }
   }
-}
 
-Config.prototype.getConfig = function () {
-  if (!this._config) {
-    this._config = _.merge({},
-      loadFile(this.options.dir, "default"),
-      loadFile(this.options.dir, this.options.environment),
-      loadFile(this.options.dir, "local")
-    )
+  getConfig() {
+    if (!this.config) {
+      const { dir, environment } = this.options;
+
+      this.config = merge(
+        {},
+        Config.loadConfigFile(dir, 'default'),
+        Config.loadConfigFile(dir, environment),
+        Config.loadConfigFile(dir, 'local')
+      );
+    }
+
+    return this.config;
   }
-  return this._config
-}
 
-Config.prototype.apply = function(compiler) {
-  // Build the configuration object
-  var config = this.getConfig()
-
-  compiler.plugin('compilation', function(compilation) {
-    // Setup a resolver to faux-resolve a request for "config"
-    compilation.resolvers.normal.plugin("module", function(request, next) {
-      if (request.request !== "config") {
-        // This plugin only resolves for the explicit module "config"
-        return next()
-      }
-
-      return next(null, {
-        // This path is not actually used but must be set to a real file
-        path: "package.json",
-        resolved: true
-      })
-    })
-  })
-
-  // Setup a module-factory to direct the flow to the loader (
-  // which outputs the configuration JSON)
-  compiler.plugin("normal-module-factory", function(nmf) {
-    nmf.plugin("after-resolve", function(data, next) {
-      if (data.rawRequest !== "config") {
-        // This plugin only resolves for the explicit module "config"
-        return next(null, data)
-      }
-
-      // console.log(data)
-      // NOTE: Parameters are passed via query string to the loader
-      //       at `this.query`
-      data.loaders = [
-        path.join(__dirname, "./config-loader.js") + "?" +
-        JSON.stringify(config)
-      ]
-
-      return next(null, data)
-    })
-  })
+  apply(compiler) {
+
+    // Build the configuration object
+    const config = this.getConfig();
+
+    compiler.plugin('compilation', compilation => {
+
+      // Setup a resolver to faux-resolve a request for "config"
+      compilation.resolvers.normal.plugin('module', (request, next) => {
+        if (request.request !== 'config') {
+
+          // This plugin only resolves for the explicit module "config"
+          return next();
+        }
+
+        return next(null, {
+
+          // This path is not actually used but must be set to a real file
+          path: 'package.json',
+          resolved: true
+        });
+      });
+    });
+
+    // Setup a module-factory to direct the flow to the loader (
+    // which outputs the configuration JSON)
+    compiler.plugin('normal-module-factory', factory => {
+      factory.plugin('after-resolve', (data, next) => {
+        if (data.rawRequest !== 'config') {
+
+          // This plugin only resolves for the explicit module "config"
+          return next(null, data);
+        }
+
+        const { filter } = this.options;
+        const loaderPathname = path.resolve(__dirname, 'config-loader.js');
+        const loaderQuery = {
+          config,
+          filter
+        };
+
+        // NOTE: Parameters are passed via query string to the loader
+        //       at `this.query`
+        data.loaders = [
+          `${loaderPathname}?${JSON.stringify(loaderQuery)}`
+        ];
+
+        return next(null, data);
+      });
+    });
+  }
 }
+
+module.exports = Config;
\ No newline at end of file
diff --git a/package.json b/package.json
index be55602..e2e7fe8 100644
--- a/package.json
+++ b/package.json
@@ -1,10 +1,10 @@
 {
   "name": "webpack-config-plugin",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "description": "Configuration plugin (in the style of node-config) for webpack.",
   "main": "lib/config-plugin.js",
-  "peerDependencies": {
-    "webpack": ">=1.4.0"
+  "engines": {
+    "node": ">=6"
   },
   "repository": {
     "type": "git",
@@ -20,12 +20,22 @@
     "email": "leckey.ryan@gmail.com",
     "url": "https://github.com/mehcode"
   },
+  "contributors": [
+    {
+      "name": "J. Snaras",
+      "email": "j@snaras.com"
+    }
+  ],
   "license": "MIT",
   "bugs": {
     "url": "https://github.com/mehcode/webpack-config-plugin/issues"
   },
   "homepage": "https://github.com/mehcode/webpack-config-plugin",
   "dependencies": {
-    "lodash": "^3.10.1"
+    "json-property-filter": "^1.3.1",
+    "lodash": "^4.17.4"
+  },
+  "peerDependencies": {
+    "webpack": ">=1.4.0"
   }
 }