diff --git a/lib/bcoin/chain.js b/lib/bcoin/chain.js
index 61bcce70..81a9a1cd 100644
--- a/lib/bcoin/chain.js
+++ b/lib/bcoin/chain.js
@@ -266,6 +266,32 @@ Chain.prototype._preload = function _preload(callback) {
     };
   }
 
+  function save(entry) {
+    if (save.locked)
+      return save.queue.push(entry);
+
+    save.locked = true;
+
+    self.db.save(entry, null, true, function(err) {
+      if (err)
+        return callback(err, 0);
+
+      save.locked = false;
+
+      if (save.queue.length === 0) {
+        if (save.ended)
+          return callback(null, height + 1);
+        return;
+      }
+
+      save(save.queue.shift());
+    });
+  }
+
+  save.locked = false;
+  save.queue = [];
+  save.ended = false;
+
   this.db.getChainHeight(function(err, chainHeight) {
     if (err)
       return callback(err);
@@ -288,7 +314,7 @@ Chain.prototype._preload = function _preload(callback) {
       var start = Math.max(0, height - 2);
       self.reset(start, function(e) {
         if (e)
-          throw e;
+          return callback(e, 0);
         return callback(err, start + 1);
       });
     });
@@ -319,7 +345,12 @@ Chain.prototype._preload = function _preload(callback) {
       blocks.forEach(function(data) {
         var block, entry, start;
 
-        data = parseHeader(data);
+        try {
+          data = parseHeader(data);
+        } catch (e) {
+          return callback(e, Math.max(0, height - 2));
+        }
+
         data.height = height;
 
         // Make sure the genesis block is correct.
@@ -334,7 +365,7 @@ Chain.prototype._preload = function _preload(callback) {
           stream.destroy();
           return self.reset(start, function(err) {
             if (err)
-              throw err;
+              return callback(err, 0);
             return callback(new Error('Corrupt headers.'), start + 1);
           });
         }
@@ -349,7 +380,7 @@ Chain.prototype._preload = function _preload(callback) {
           stream.destroy();
           return self.reset(start, function(err) {
             if (err)
-              throw err;
+              return callback(err, 0);
             return callback(new Error('Bad headers.'), start + 1);
           });
         }
@@ -360,7 +391,7 @@ Chain.prototype._preload = function _preload(callback) {
         if (entry.height <= chainHeight)
           self.db.addCache(entry);
         else
-          self.db.save(entry, null, true);
+          save(entry);
 
         if ((height + 1) % 50000 === 0)
           utils.debug('Received %d headers from electrum.org.', height + 1);
@@ -371,7 +402,9 @@ Chain.prototype._preload = function _preload(callback) {
     });
 
     stream.on('end', function() {
-      return callback(null, height + 1);
+      save.ended = true;
+      if (!save.locked && save.queue.length === 0)
+        return callback(null, height + 1);
     });
   });
 };
@@ -909,8 +942,12 @@ Chain.prototype._setBestChain = function _setBestChain(entry, block, callback) {
 
   // We don't have a genesis block yet.
   if (!this.tip) {
-    if (entry.hash !== network.genesis.hash)
-      return utils.asyncify(callback)(new Error('Bad genesis block.'));
+    if (entry.hash !== network.genesis.hash) {
+      return utils.asyncify(callback)(new VerifyError(block,
+        'invalid',
+        'bad-genblk',
+        100));
+    }
 
     return done();
   }
@@ -946,13 +983,11 @@ Chain.prototype.reset = function reset(height, callback, force) {
   if (!unlock)
     return;
 
-  callback = utils.ensure(callback);
+  callback = utils.wrap(callback, unlock);
 
   this.db.reset(height, function(err, result) {
-    if (err) {
-      unlock();
+    if (err)
       return callback(err);
-    }
 
     // Reset the orphan map completely. There may
     // have been some orphans on a forked chain we
@@ -960,7 +995,6 @@ Chain.prototype.reset = function reset(height, callback, force) {
     self.purgeOrphans();
     self.purgePending();
 
-    unlock();
     callback(null, result);
   });
 };
@@ -972,25 +1006,16 @@ Chain.prototype.resetTime = function resetTime(ts, callback, force) {
   if (!unlock)
     return;
 
-  callback = utils.ensure(callback);
+  callback = utils.wrap(callback, unlock);
 
   this.byTime(ts, function(err, entry) {
-    if (err) {
-      unlock();
-      callback(err);
-      return;
-    }
+    if (err)
+      return callback(err);
 
-    if (!entry) {
-      unlock();
-      callback();
-      return;
-    }
+    if (!entry)
+      return callback();
 
-    self.reset(entry.height, function(err) {
-      unlock();
-      callback(err);
-    }, true);
+    self.reset(entry.height, callback, true);
   }, true);
 };
 
@@ -1009,6 +1034,8 @@ Chain.prototype.add = function add(block, callback, force) {
   if (!unlock)
     return;
 
+  callback = utils.wrap(callback, unlock);
+
   (function next(block, initial) {
     var hash = block.hash('hex');
     var prevHash = block.prevBlock;
@@ -1240,13 +1267,15 @@ Chain.prototype.add = function add(block, callback, force) {
 
             // Emit our block (and potentially resolved
             // orphan) only if it is on the main chain.
-            if (mainChain)
+            if (mainChain) {
               self.emit('block', block, entry);
-            else
+              if (!initial)
+                self.emit('resolved', block, entry);
+            } else {
               self.emit('competitor', block, entry);
-
-            if (!initial)
-              self.emit('resolved', block, entry);
+              if (!initial)
+                self.emit('competitor resolved', block, entry);
+            }
 
             // No orphan chain.
             if (!self.orphan.map[hash])
@@ -1285,8 +1314,6 @@ Chain.prototype.add = function add(block, callback, force) {
       if (self.isFull())
         self.emit('full');
 
-      unlock();
-
       if (err)
         callback(err);
       else
@@ -1368,31 +1395,23 @@ Chain.prototype.byTime = function byTime(ts, callback, force) {
   var end = this.height;
   var pos, delta;
 
-  var unlock = this._lock(byTime, [ts, callback], force);
-  if (!unlock)
-    return;
-
-  callback = utils.asyncify(callback);
+  // var unlock = this._lock(byTime, [ts, callback], force);
+  // if (!unlock)
+  //   return;
+  // callback = utils.wrap(callback, unlock);
 
   function done(err, result) {
-    if (err) {
-      unlock();
+    if (err)
       return callback(err);
-    }
 
-    if (result) {
-      unlock();
+    if (result)
       return callback(null, result);
-    }
 
-    self.db.get(start, function(err, entry) {
-      unlock();
-      callback(err, entry);
-    });
+    self.db.get(start, callback);
   }
 
   if (ts >= this.tip.ts)
-    return done(null, this.tip);
+    return utils.asyncify(done)(null, this.tip);
 
   // Do a binary search for a block
   // mined within an hour of the
@@ -1501,29 +1520,25 @@ Chain.prototype.getProgress = function getProgress() {
 Chain.prototype.getHashRange = function getHashRange(start, end, callback, force) {
   var self = this;
 
-  var unlock = this._lock(getHashRange, [start, end, callback], force);
-  if (!unlock)
-    return;
-
-  function done(err, result) {
-    unlock();
-    callback(err, result);
-  }
+  // var unlock = this._lock(getHashRange, [start, end, callback], force);
+  // if (!unlock)
+  //   return;
+  // callback = utils.wrap(callback, unlock);
 
   this.byTime(start, function(err, start) {
     if (err)
-      return done(err);
+      return callback(err);
 
     self.byTime(end, function(err, end) {
       var hashes;
 
       if (err)
-        return done(err);
+        return callback(err);
 
       hashes = [];
 
       if (!start || !end)
-        return done(null, hashes);
+        return callback(null, hashes);
 
       utils.forRange(start.height, end.height + 1, function(i, next) {
         self.db.get(i, function(err, entry) {
@@ -1539,8 +1554,8 @@ Chain.prototype.getHashRange = function getHashRange(start, end, callback, force
         });
       }, function(err) {
         if (err)
-          return done(err);
-        return done(null, hashes);
+          return callback(err);
+        return callback(null, hashes);
       });
     }, true);
   }, true);
@@ -1556,6 +1571,7 @@ Chain.prototype.getLocator = function getLocator(start, callback, force) {
   var unlock = this._lock(getLocator, [start, callback], force);
   if (!unlock)
     return;
+  callback = utils.wrap(callback, unlock);
 
   if (start) {
     if (Buffer.isBuffer(start))
@@ -1589,10 +1605,8 @@ Chain.prototype.getLocator = function getLocator(start, callback, force) {
   }
 
   return getTop(function(err, top) {
-    if (err) {
-      unlock();
+    if (err)
       return callback(err);
-    }
 
     i = top;
     for (;;) {
@@ -1622,7 +1636,6 @@ Chain.prototype.getLocator = function getLocator(start, callback, force) {
         next();
       });
     }, function(err) {
-      unlock();
       if (err)
         return callback(err);
       return callback(null, hashes);
@@ -1952,11 +1965,10 @@ Chain.prototype.isSegwitActive = function isSegwitActive(callback) {
   if (!this.tip)
     return utils.asyncify(callback)(null, false);
 
-  unlock = this._lock(isSegwitActive, [callback]);
-  if (!unlock)
-    return;
-
-  callback = utils.wrap(callback, unlock);
+  // unlock = this._lock(isSegwitActive, [callback]);
+  // if (!unlock)
+  //   return;
+  // callback = utils.wrap(callback, unlock);
 
   if (network.type === 'segnet4') {
     return this.tip.getPrevious(function(err, prev) {
@@ -2090,6 +2102,12 @@ Chain.prototype.evalLocks = function evalLocks(entry, minHeight, minTime, callba
 
 Chain.prototype.checkLocks = function checkLocks(tx, flags, entry, callback) {
   var self = this;
+
+  // var unlock = this._lock(checkLocks, [tx, flags, entry, callback], force);
+  // if (!unlock)
+  //   return;
+  // callback = utils.wrap(callback, unlock);
+
   this.getLocks(tx, flags, entry, function(err, minHeight, minTime) {
     if (err)
       return callback(err);
diff --git a/lib/bcoin/peer.js b/lib/bcoin/peer.js
index 17c9c14a..6cc26e84 100644
--- a/lib/bcoin/peer.js
+++ b/lib/bcoin/peer.js
@@ -140,6 +140,7 @@ Peer.prototype._init = function init() {
 
   this.parser.on('error', function(err) {
     utils.debug(err.stack + '');
+    peer.sendReject(null, 'malformed', 'error parsing message', 100);
     self._error(err);
     // Something is wrong here.
     // Ignore this peer.
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index d1cc5687..fab7a3d2 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -1925,19 +1925,28 @@ Pool.prototype.isMisbehaving = function isMisbehaving(host) {
 };
 
 Pool.prototype.reject = function reject(peer, obj, code, reason, score) {
+  if (obj) {
+    utils.debug('Rejecting %s %s from %s: ccode=%s reason=%s',
+      obj.type, obj.hash('hex'), peer.host, code, reason);
+
+    peer.reject({
+      ccode: code,
+      reason: reason,
+      data: obj.hash()
+    });
+  } else {
+    utils.debug('Rejecting packet from %s: ccode=%s reason=%s',
+      peer.host, code, reason);
+
+    peer.reject({
+      ccode: code,
+      reason: reason,
+      data: null
+    });
+  }
+
   if (score != null)
     peer.setMisbehavior(score);
-
-  utils.debug('Rejecting %s %s: ccode=%s reason=%s',
-    obj.type, obj.hash('hex'), code, reason);
-
-  peer.reject({
-    ccode: code,
-    reason: reason,
-    data: obj.hash()
-  });
-
-  return false;
 };
 
 /**