diff --git a/README.md b/README.md
index 7db5abf1..2c496a1c 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ Docs need to be rewritten. They're coming soon. I promise.
 ### High-level usage for Node object
 
 ``` js
-var bcoin = require('bcoin');
+var bcoin = require('bcoin')('main');
 
 var node = bcoin.fullnode({
   prune: false,
@@ -136,8 +136,7 @@ $ node bin/bcoin-cli mempool
 ### Creating a blockchain and mempool
 
 ``` js
-var bcoin = require('bcoin');
-bcoin.protocol.network.set('regtest');
+var bcoin = require('bcoin')('regtest');
 var chain = new bcoin.chain({ db: 'memory' });
 var mempool = new bcoin.mempool({ chain: chain, db: 'memory' });
 var miner = new bcoin.miner({ chain: chain, mempool: mempool });
diff --git a/lib/bcoin/ldb.js b/lib/bcoin/ldb.js
index 7f1edadb..98f694dc 100644
--- a/lib/bcoin/ldb.js
+++ b/lib/bcoin/ldb.js
@@ -36,6 +36,7 @@ function ldb(options) {
       maxOpenFiles: options.maxOpenFiles || 8192,
       filterBits: 0,
       paranoidChecks: false,
+      memory: false,
 
       // For LMDB if we decide to use it:
       sync: options.sync || false,
diff --git a/lib/bcoin/miner.js b/lib/bcoin/miner.js
index 540a163f..ae2450f3 100644
--- a/lib/bcoin/miner.js
+++ b/lib/bcoin/miner.js
@@ -110,25 +110,22 @@ Miner.prototype._init = function _init() {
       stat.best);
   });
 
-  this.chain.open(function(err) {
+  function done(err) {
     if (err)
       return self.emit('error', err);
     self.loaded = true;
     self.emit('open');
-  });
+  }
+
+  if (this.mempool)
+    this.mempool.open(done);
+  else
+    this.chain.open(done);
 };
 
 Miner.prototype.start = function start() {
   var self = this;
 
-  // Wait for `tip`.
-  if (!this.chain.tip) {
-    this.chain.on('tip', function(tip) {
-      self.start();
-    });
-    return;
-  }
-
   this.stop();
 
   this.running = true;
@@ -189,6 +186,17 @@ Miner.prototype.createBlock = function createBlock(callback) {
   var ts = Math.max(utils.now(), this.chain.tip.ts + 1);
   var attempt;
 
+  if (!this.loaded) {
+    this.open(function(err) {
+      if (err)
+        return callback(err);
+      self.createBlock(callback);
+    });
+    return;
+  }
+
+  assert(this.chain.tip);
+
   // Find target
   this.chain.getTargetAsync(this.chain.tip, ts, function(err, target) {
     if (err)
@@ -520,7 +528,6 @@ function rcmp(a, b) {
  * Expose
  */
 
-var exports = Miner;
-exports.minerblock = MinerBlock;
-return exports;
+Miner.minerblock = MinerBlock;
+return Miner;
 };
diff --git a/lib/bcoin/mtx.js b/lib/bcoin/mtx.js
index 98f90986..73299e75 100644
--- a/lib/bcoin/mtx.js
+++ b/lib/bcoin/mtx.js
@@ -37,7 +37,7 @@ function MTX(options) {
   this.ts = 0;
   this.block = null;
   this.index = -1;
-  this.ps = this.ts === 0 ? utils.now() : 0;
+  this.ps = options.ps != null ? options.ps : utils.now();
   this.changeIndex = options.changeIndex != null ? options.changeIndex : -1;
   this.height = -1;
 
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index 05ac2110..da026bf9 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -43,6 +43,13 @@ function Pool(options) {
       options.relay = true;
   }
 
+  if (options.headers == null) {
+    if (options.spv)
+      options.headers = true;
+    else
+      options.headers = false;
+  }
+
   seeds = (options.seeds || network.seeds).slice();
 
   if (process.env.BCOIN_SEED)
@@ -59,14 +66,6 @@ function Pool(options) {
   this.size = options.size || 8;
   this.connected = false;
 
-  if (options.spv) {
-    if (options.headers == null)
-      options.headers = true;
-  } else {
-    if (options.headers == null)
-      options.headers = false;
-  }
-
   this.syncing = false;
   this.synced = false;
   this._scheduled = false;
@@ -140,7 +139,7 @@ function Pool(options) {
     timeout: options.invTimeout || 60000
   };
 
-  this.chain.open(function(err) {
+  function done(err) {
     if (err)
       return self.emit('error', err);
 
@@ -148,7 +147,12 @@ function Pool(options) {
     self.emit('open');
 
     self._init();
-  });
+  }
+
+  if (this.mempool)
+    this.mempool.open(done);
+  else
+    this.chain.open(done);
 }
 
 utils.inherits(Pool, EventEmitter);
diff --git a/lib/bcoin/tx.js b/lib/bcoin/tx.js
index 959d57d2..6240cfb0 100644
--- a/lib/bcoin/tx.js
+++ b/lib/bcoin/tx.js
@@ -40,7 +40,7 @@ function TX(data, block, index) {
   this.ts = data.ts || 0;
   this.block = data.block || null;
   this.index = data.index != null ? data.index : -1;
-  this.ps = this.ts === 0 ? utils.now() : 0;
+  this.ps = this.ts === 0 ? (data.ps != null ? data.ps : utils.now()) : 0;
   this.height = data.height != null ? data.height : -1;
 
   this._hash = null;
@@ -1223,7 +1223,9 @@ TX.prototype.inspect = function inspect() {
     date: new Date(this.ts * 1000).toISOString(),
     block: this.block ? utils.revHex(this.block) : null,
     ts: this.ts,
+    ps: this.ps,
     index: this.index,
+    changeIndex: this.changeIndex || -1,
     version: this.version,
     inputs: this.inputs,
     outputs: this.outputs,