diff --git a/browser/index.js b/browser/index.js
index 43469290..e49a381c 100644
--- a/browser/index.js
+++ b/browser/index.js
@@ -235,6 +235,8 @@ node = new bcoin.fullnode({
   coinCache: 30000000,
   logConsole: true,
   workers: true,
+  workerURL: '/bcoin-worker.js',
+  masterURL: '/bcoin-master.js',
   logger: logger
 });
 
diff --git a/lib/node/node.js b/lib/node/node.js
index 16ec7d6d..8e94c7cc 100644
--- a/lib/node/node.js
+++ b/lib/node/node.js
@@ -88,7 +88,10 @@ Node.prototype.initOptions = function initOptions() {
   this.workers = new WorkerPool({
     enabled: config.bool('workers'),
     size: config.num('workers-size'),
-    timeout: config.num('workers-timeout')
+    timeout: config.num('workers-timeout'),
+    workerFile: config.str('worker-file'),
+    workerURL: config.str('worker-url'),
+    masterURL: config.str('master-url')
   });
 };
 
diff --git a/lib/workers/master.js b/lib/workers/master.js
index 28e35d3f..6bf3785b 100644
--- a/lib/workers/master.js
+++ b/lib/workers/master.js
@@ -84,7 +84,9 @@ Master.prototype._initWebWorkers = function _initWebWorkers() {
   global.onmessage = (event) => {
     let data;
     if (typeof event.data !== 'string') {
-      data = event.data.buf;
+      assert(event.data && typeof event.data === 'object');
+      assert(event.data.data);
+      data = event.data.data;
       data.__proto__ = Buffer.prototype;
     } else {
       data = Buffer.from(event.data, 'hex');
@@ -110,7 +112,7 @@ Master.prototype._initChildProcess = function _initChildProcess() {
 
   process.on('uncaughtException', (err) => {
     this.send(new packets.ErrorPacket(err));
-    setImmediate(() => process.exit(1));
+    setTimeout(() => process.exit(1), 500);
   });
 };
 
@@ -133,7 +135,7 @@ Master.prototype.write = function write(data) {
   if (HAS_WORKERS) {
     if (global.postMessage.length === 2) {
       data.__proto__ = Uint8Array.prototype;
-      global.postMessage({ buf: data }, [data]);
+      global.postMessage({ data }, [data]);
     } else {
       global.postMessage(data.toString('hex'));
     }
diff --git a/lib/workers/workerpool.js b/lib/workers/workerpool.js
index b732e3e8..86e5b2eb 100644
--- a/lib/workers/workerpool.js
+++ b/lib/workers/workerpool.js
@@ -52,6 +52,10 @@ function WorkerPool(options) {
   this.nonce = 0;
   this.enabled = true;
 
+  this.workerFile = WorkerPool.WORKER_FILE;
+  this.workerURL = WorkerPool.WORKER_URL;
+  this.masterURL = WorkerPool.MASTER_URL;
+
   bindExit();
   pools.add(this);
 
@@ -72,21 +76,21 @@ WorkerPool.CORES = getCores();
  * @const {String}
  */
 
-WorkerPool.WORKER_FILE = 'worker.js';
+WorkerPool.WORKER_FILE = process.env.BCOIN_WORKER_FILE || 'worker.js';
 
 /**
  * Default worker URL.
  * @const {String}
  */
 
-WorkerPool.WORKER_URL = '/bcoin-worker.js';
+WorkerPool.WORKER_URL = process.env.BCOIN_WORKER_URL || '/bcoin-worker.js';
 
 /**
  * Default master URL.
  * @const {String}
  */
 
-WorkerPool.MASTER_URL = '/bcoin-master.js';
+WorkerPool.MASTER_URL = process.env.BCOIN_MASTER_URL || '/bcoin-master.js';
 
 /**
  * Set worker pool options.
@@ -113,6 +117,21 @@ WorkerPool.prototype.set = function set(options) {
     assert(options.timeout > 0);
     this.timeout = options.timeout;
   }
+
+  if (options.workerFile != null) {
+    assert(typeof options.workerFile === 'string');
+    this.workerFile = options.workerFile;
+  }
+
+  if (options.workerURL != null) {
+    assert(typeof options.workerURL === 'string');
+    this.workerURL = options.workerURL;
+  }
+
+  if (options.masterURL != null) {
+    assert(typeof options.masterURL === 'string');
+    this.masterURL = options.masterURL;
+  }
 };
 
 /**
@@ -414,7 +433,7 @@ function Worker(id) {
   this.pending = new Map();
 
   this.env = {
-    BCOIN_MASTER_URL: process.env.BCOIN_MASTER_URL || WorkerPool.MASTER_URL,
+    BCOIN_MASTER_URL: this.masterURL,
     BCOIN_WORKER_NETWORK: Network.type,
     BCOIN_WORKER_ISTTY: process.stdout
       ? (process.stdout.isTTY ? '1' : '0')
@@ -463,12 +482,7 @@ Worker.prototype._init = function _init() {
  */
 
 Worker.prototype._initWebWorkers = function _initWebWorkers() {
-  let file = WorkerPool.WORKER_URL;
-
-  if (process.env.BCOIN_WORKER_URL)
-    file = process.env.BCOIN_WORKER_URL;
-
-  this.child = new global.Worker(file);
+  this.child = new global.Worker(this.workerURL);
 
   this.child.onerror = (err) => {
     this.emit('error', err);
@@ -478,7 +492,9 @@ Worker.prototype._initWebWorkers = function _initWebWorkers() {
   this.child.onmessage = (event) => {
     let data;
     if (typeof event.data !== 'string') {
-      data = event.data.buf;
+      assert(event.data && typeof event.data === 'object');
+      assert(event.data.data);
+      data = event.data.data;
       data.__proto__ = Buffer.prototype;
     } else {
       data = Buffer.from(event.data, 'hex');
@@ -496,15 +512,10 @@ Worker.prototype._initWebWorkers = function _initWebWorkers() {
 
 Worker.prototype._initChildProcess = function _initChildProcess() {
   let bin = process.argv[0];
-  let file = WorkerPool.WORKER_FILE;
+  let file = path.resolve(__dirname, this.workerFile);
   let env = Object.assign({}, process.env, this.env);
   let options = { stdio: 'pipe', env: env };
 
-  if (process.env.BCOIN_WORKER_FILE)
-    file = process.env.BCOIN_WORKER_FILE;
-
-  file = path.resolve(__dirname, file);
-
   this.child = cp.spawn(bin, [file], options);
 
   this.child.unref();
@@ -601,7 +612,7 @@ Worker.prototype.write = function write(data) {
   if (HAS_WORKERS) {
     if (this.child.postMessage.length === 2) {
       data.__proto__ = Uint8Array.prototype;
-      this.child.postMessage({ buf: data }, [data]);
+      this.child.postMessage({ data }, [data]);
     } else {
       this.child.postMessage(data.toString('hex'));
     }