diff --git a/lib/bcoin.js b/lib/bcoin.js
index 6aa91fee..dc8ad7ac 100644
--- a/lib/bcoin.js
+++ b/lib/bcoin.js
@@ -11,9 +11,26 @@ bcoin.isBrowser =
   (typeof process !== 'undefined' && process.browser)
   || typeof window !== 'undefined';
 
+bcoin.prefix = process.env.BCOIN_PREFIX || process.env.HOME + '/.bcoin';
 bcoin.debug = +process.env.BCOIN_DEBUG === 1;
 bcoin.debugFile = +process.env.BCOIN_DEBUGFILE !== 0;
 
+bcoin.ensurePrefix = function ensurePrefix() {
+  if (!bcoin.fs)
+    return;
+
+  if (bcoin._ensured)
+    return;
+
+  bcoin._ensured = true;
+
+  try {
+    bcoin.fs.statSync(bcoin.prefix);
+  } catch (e) {
+    bcoin.fs.mkdirSync(bcoin.prefix, 0750);
+  }
+};
+
 bcoin.bn = require('bn.js');
 bcoin.elliptic = require('elliptic');
 
@@ -32,16 +49,6 @@ if (!bcoin.isBrowser) {
   bcoin.hash = require('hash.js');
 }
 
-bcoin.dir = process.env.HOME + '/.bcoin';
-
-if (bcoin.fs) {
-  try {
-    bcoin.fs.statSync(bcoin.dir, 0o750);
-  } catch (e) {
-    bcoin.fs.mkdirSync(bcoin.dir);
-  }
-}
-
 bcoin.ecdsa = bcoin.elliptic.ec('secp256k1');
 assert(!bcoin.ecdsa.signature);
 bcoin.ecdsa.signature = require('elliptic/lib/elliptic/ec/signature');
diff --git a/lib/bcoin/blockdb.js b/lib/bcoin/blockdb.js
index 471d348c..5154dd38 100644
--- a/lib/bcoin/blockdb.js
+++ b/lib/bcoin/blockdb.js
@@ -32,8 +32,10 @@ function BlockDB(options) {
 
   this.file = options.indexFile;
 
+  bcoin.ensurePrefix();
+
   if (!this.file)
-    this.file = bcoin.dir + '/index-' + network.type + '.db';
+    this.file = bcoin.prefix + '/index-' + network.type + '.db';
 
   this.options = options;
 
@@ -1078,8 +1080,10 @@ function BlockData(options) {
   this.options = options;
   this.file = options.blockFile;
 
+  bcoin.ensurePrefix();
+
   if (!this.file)
-    this.file = bcoin.dir + '/block-' + network.type + '.db';
+    this.file = bcoin.prefix + '/block-' + network.type + '.db';
 
   this.bufferPool = { used: {} };
   this.size = 0;
diff --git a/lib/bcoin/chaindb.js b/lib/bcoin/chaindb.js
index b93034f8..15b4c9cc 100644
--- a/lib/bcoin/chaindb.js
+++ b/lib/bcoin/chaindb.js
@@ -34,7 +34,7 @@ function ChainDB(chain, options) {
   this.file = options.file;
 
   if (!this.file)
-    this.file = bcoin.dir + '/chain-' + network.type + '.db';
+    this.file = bcoin.prefix + '/chain-' + network.type + '.db';
 
   this.heightLookup = {};
   this.queue = {};
@@ -81,6 +81,8 @@ ChainDB.prototype._init = function _init() {
     return;
   }
 
+  bcoin.ensurePrefix();
+
   if (+process.env.BCOIN_FRESH === 1) {
     try {
       fs.unlinkSync(this.file);
diff --git a/lib/bcoin/utils.js b/lib/bcoin/utils.js
index 3631423c..912a7aa0 100644
--- a/lib/bcoin/utils.js
+++ b/lib/bcoin/utils.js
@@ -766,8 +766,9 @@ utils.debug = function debug() {
 
   if (bcoin.debugFile && bcoin.fs) {
     if (!bcoin._debug) {
+      bcoin.ensurePrefix();
       bcoin._debug = bcoin.fs.createWriteStream(
-        bcoin.dir + '/debug.log', { flags: 'a' });
+        bcoin.prefix + '/debug.log', { flags: 'a' });
     }
     msg = utils.format(args, false);
     bcoin._debug.write(process.pid + ': ' + msg);
diff --git a/lib/bcoin/walletdb.js b/lib/bcoin/walletdb.js
index 424625c2..c522ecff 100644
--- a/lib/bcoin/walletdb.js
+++ b/lib/bcoin/walletdb.js
@@ -37,11 +37,13 @@ function WalletDB(options) {
   this.dir = options.dir;
   this.type = options.type;
 
+  bcoin.ensurePrefix();
+
   if (!this.file)
-    this.file = bcoin.dir + '/wallet-' + network.type + '.db';
+    this.file = bcoin.prefix + '/wallet-' + network.type + '.db';
 
   if (!this.dir)
-    this.dir = bcoin.dir + '/wallet-' + network.type;
+    this.dir = bcoin.prefix + '/wallet-' + network.type;
 
   if (!this.type)
     this.type = 'leveldb';
@@ -66,9 +68,9 @@ WalletDB.prototype._init = function _init() {
   if (this.type === 'file') {
     if (bcoin.fs) {
       try {
-        bcoin.fs.statSync(this.dir, 0o750);
+        bcoin.fs.statSync(this.dir);
       } catch (e) {
-        bcoin.fs.mkdirSync(this.dir);
+        bcoin.fs.mkdirSync(this.dir, 0750);
       }
     }
     if (+process.env.BCOIN_FRESH === 1) {
@@ -160,7 +162,7 @@ WalletDB.prototype.saveFile = function saveFile(id, json, callback) {
 
   options = {
     encoding: 'utf8',
-    mode: 0o600
+    mode: 0600
   };
 
   fs.writeFile(file, json, options, function(err) {