diff --git a/lib/bcoin/block.js b/lib/bcoin/block.js
index 62649e66..7c010f61 100644
--- a/lib/bcoin/block.js
+++ b/lib/bcoin/block.js
@@ -100,47 +100,54 @@ Block.prototype.getMerkleRoot = function getMerkleRoot() {
   root = utils.getMerkleRoot(leaves);
 
   if (!root)
-    return utils.toHex(constants.zeroHash);
+    return;
 
   return utils.toHex(root);
 };
 
-Block.prototype.getWitnessRoot = function getWitnessRoot() {
+Block.prototype.getCommitmentHash = function getCommitmentHash() {
   var leaves = [];
-  var i, root;
+  var i, witnessNonce, witnessRoot, commitmentHash;
+
+  witnessNonce = this.txs[0].inputs[0].witness[0];
+
+  if (!witnessNonce)
+    return;
 
   for (i = 0; i < this.txs.length; i++)
     leaves.push(this.txs[i].witnessHash());
 
-  root = utils.getMerkleRoot(leaves);
+  witnessRoot = utils.getMerkleRoot(leaves);
 
-  if (!root)
-    return utils.toHex(constants.zeroHash);
+  if (!witnessRoot)
+    return;
 
-  return utils.toHex(root);
+  commitmentHash = utils.dsha256(Buffer.concat([witnessRoot, witnessNonce]));
+
+  return utils.toHex(commitmentHash);
 };
 
-Block.prototype.__defineGetter__('witnessRoot', function() {
-  var coinbase, i, commitment, witnessRoot;
+Block.prototype.__defineGetter__('commitmentHash', function() {
+  var coinbase, i, commitment, witnessNonce, commitmentHash;
 
-  if (this._witnessRoot)
-    return this._witnessRoot;
+  if (this._commitmentHash)
+    return this._commitmentHash;
 
-  coinbase = block.txs[0];
+  coinbase = this.txs[0];
 
   // Find the fucking commitment for segregated shitness
   for (i = 0; i < coinbase.outputs.length; i++) {
     commitment = coinbase.outputs[i].script;
     if (bcoin.script.isCommitment(commitment)) {
-      witnessRoot = bcoin.script.getWitnessRoot(commitment);
+      commitmentHash = bcoin.script.getCommitmentHash(commitment);
       break;
     }
   }
 
-  if (witnessRoot)
-    this._witnessRoot = utils.toHex(witnessRoot);
+  if (commitmentHash)
+    this._commitmentHash = utils.toHex(commitmentHash);
 
-  return this._witnessRoot;
+  return this._commitmentHash;
 });
 
 Block.prototype._verify = function _verify() {
@@ -296,7 +303,7 @@ Block.prototype.inspect = function inspect() {
     version: this.version,
     prevBlock: utils.revHex(this.prevBlock),
     merkleRoot: utils.revHex(this.merkleRoot),
-    witnessRoot: utils.revHex(this.witnessRoot),
+    commitmentHash: this.commitmentHash ? utils.revHex(this.commitmentHash) : null,
     ts: this.ts,
     bits: this.bits,
     nonce: this.nonce,
@@ -313,7 +320,7 @@ Block.prototype.toJSON = function toJSON() {
     version: this.version,
     prevBlock: utils.revHex(this.prevBlock),
     merkleRoot: utils.revHex(this.merkleRoot),
-    witnessRoot: utils.revHex(this.witnessRoot),
+    commitmentHash: this.commitmentHash ? utils.revHex(this.commitmentHash) : null,
     ts: this.ts,
     bits: this.bits,
     nonce: this.nonce,
diff --git a/lib/bcoin/chain.js b/lib/bcoin/chain.js
index 894f8e9e..7e6d2f71 100644
--- a/lib/bcoin/chain.js
+++ b/lib/bcoin/chain.js
@@ -455,7 +455,7 @@ Chain.prototype._verifyContext = function _verifyContext(block, prev, callback)
 Chain.prototype._verify = function _verify(block, prev) {
   var flags = constants.flags.MANDATORY_VERIFY_FLAGS;
   var height, ts, i, tx, cb, coinbaseHeight, medianTime;
-  var locktimeMedian, coinbase, commitment, segwit, witnessRoot;
+  var locktimeMedian, coinbase, commitment, segwit;
 
   if (!block.verify())
     return flags;
@@ -534,8 +534,10 @@ Chain.prototype._verify = function _verify(block, prev) {
   // }
 
   // Make sure the height contained in the coinbase is correct.
-  if (block.version >= 2 && prev.isUpgraded(2))
-    coinbaseHeight = true;
+  if (network.block.bip34height !== -1 && height >= network.block.bip34height) {
+    if (block.version >= 2 && prev.isUpgraded(2))
+      coinbaseHeight = true;
+  }
 
   // Signature validation is now enforced (bip66)
   if (block.version >= 3 && prev.isUpgraded(3))
@@ -546,8 +548,8 @@ Chain.prototype._verify = function _verify(block, prev) {
     flags |= constants.flags.VERIFY_CHECKLOCKTIMEVERIFY;
 
   // Segregrated witness is now usable (the-bip-that-really-needs-to-be-rewritten)
-  if (height >= network.segwitHeight) {
-    if (block.witness && block.version >= 5 && prev.isUpgraded(5) ) {
+  if (network.segwitHeight !== -1 && height >= network.segwitHeight) {
+    if (block.version >= 5 && prev.isUpgraded(5) ) {
       flags |= constants.flags.VERIFY_WITNESS;
       segwit = true;
     }
@@ -573,8 +575,8 @@ Chain.prototype._verify = function _verify(block, prev) {
     }
   }
 
-  if (segwit && block.witness) {
-    if (block.witnessRoot !== block.getWitnessRoot()) {
+  if (segwit) {
+    if (block._witness && block.commitmentHash !== block.getCommitmentHash()) {
       utils.debug('Block failed witnessroot test: %s', block.rhash);
       return false;
     }
diff --git a/lib/bcoin/hd.js b/lib/bcoin/hd.js
index 93401e1e..dd45e04d 100644
--- a/lib/bcoin/hd.js
+++ b/lib/bcoin/hd.js
@@ -505,7 +505,7 @@ HDPrivateKey.isExtended = function isExtended(data) {
   if (typeof data !== 'string')
     return false;
 
-  return data.indexOf('xprv') === 0 || data.indexOf('tprv') === 0;
+  return network.xprivkeys[data.slice(0, 4)];
 };
 
 HDPrivateKey.prototype._normalize = function _normalize(data) {
@@ -978,7 +978,7 @@ HDPublicKey.isExtended = function isExtended(data) {
   if (typeof data !== 'string')
     return false;
 
-  return data.indexOf('xpub') === 0 || data.indexOf('tpub') === 0;
+  return network.xpubkeys[data.slice(0, 4)];
 };
 
 HDPublicKey.prototype._normalize = HDPrivateKey.prototype._normalize;
diff --git a/lib/bcoin/input.js b/lib/bcoin/input.js
index be5a548f..93b3b19f 100644
--- a/lib/bcoin/input.js
+++ b/lib/bcoin/input.js
@@ -82,7 +82,7 @@ Input.prototype.getRedeem = function getRedeem() {
 
   if (type === 'scripthash') {
     redeem = bcoin.script.getRedeem(this.script);
-    if (script.isWitnessScripthash(redeem))
+    if (bcoin.script.isWitnessScripthash(redeem))
       return bcoin.script.getRedeem(this.witness);
     return redeem;
   }
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index 80a26773..536632fc 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -114,9 +114,15 @@ function Pool(options) {
 
   this.tx = {
     state: {},
-    count: 0
+    count: 0,
+    type: 'tx'
   };
 
+  if (network.type === 'segnet') {
+    this.block.type = 'witness' + this.block.type;
+    this.tx.type = 'witness' + this.tx.type;
+  }
+
   this.request = {
     map: {},
     active: 0,
@@ -695,7 +701,8 @@ Pool.prototype._handleBlock = function _handleBlock(block, peer, callback) {
       if (self.chain.height % 20 === 0) {
         utils.debug(
           'Status: tip=%s ts=%s height=%d blocks=%d orphans=%d active=%d'
-          + ' queue=%d target=%s peers=%d pending=%d highest=%d jobs=%d',
+          + ' queue=%d target=%s peers=%d pending=%d highest=%d jobs=%d'
+          + ' blockdelta=%d',
           block.rhash,
           new Date(block.ts * 1000).toISOString().slice(0, -5) + 'Z',
           self.chain.height,
@@ -707,7 +714,8 @@ Pool.prototype._handleBlock = function _handleBlock(block, peer, callback) {
           self.peers.all.length,
           self.chain.pending.length,
           self.chain.bestHeight,
-          self.chain.jobs.length);
+          self.chain.jobs.length,
+          self.chain.blockDelta);
       }
 
       return callback(null, true);
@@ -805,7 +813,7 @@ Pool.prototype._createPeer = function _createPeer(options) {
     txs.forEach(function(hash) {
       hash = utils.toHex(hash);
       if (self.markTX(hash, 0))
-        self.getData(peer, 'tx', hash);
+        self.getData(peer, self.tx.type, hash);
     });
   });
 
@@ -1473,7 +1481,7 @@ Pool.prototype.getData = function getData(peer, type, hash, options, callback) {
     return;
   }
 
-  if (!options.force && type !== 'tx') {
+  if (!options.force && type !== self.tx.type) {
     if (this.chain.has(hash))
       return;
   }
@@ -1483,7 +1491,7 @@ Pool.prototype.getData = function getData(peer, type, hash, options, callback) {
 
   item = new LoadRequest(this, peer, type, hash, callback);
 
-  if (type === 'tx') {
+  if (type === self.tx.type) {
     if (peer.queue.tx.length === 0) {
       utils.nextTick(function() {
         utils.debug(
@@ -1614,7 +1622,7 @@ Pool.prototype.getTX = function getTX(hash, range, callback) {
   // Add request without queueing it to get notification at the time of load
   tx = null;
   found = false;
-  this.getData(this.peers.load, 'tx', hash, { noQueue: true }, function(t) {
+  this.getData(this.peers.load, self.tx.type, hash, { noQueue: true }, function(t) {
     found = true;
     tx = t;
   });
@@ -1926,7 +1934,7 @@ LoadRequest.prototype.start = function start() {
   this.peer.on('close', this._finish);
 
   this.pool.request.active++;
-  if (this.type === 'tx')
+  if (this.type === this.pool.tx.type)
     this.pool.request.activeTX++;
   else
     this.pool.request.activeBlocks++;
@@ -1940,13 +1948,13 @@ LoadRequest.prototype.finish = function finish() {
   if (this.pool.request.map[this.hash]) {
     delete this.pool.request.map[this.hash];
     this.pool.request.active--;
-    if (this.type === 'tx')
+    if (this.type === this.pool.tx.type)
       this.pool.request.activeTX--;
     else
       this.pool.request.activeBlocks--;
   }
 
-  if (this.type === 'tx') {
+  if (this.type === this.pool.tx.type) {
     index = this.peer.queue.tx.indexOf(this);
     if (index !== -1)
       this.peer.queue.tx.splice(index, 1);
diff --git a/lib/bcoin/protocol/network.js b/lib/bcoin/protocol/network.js
index 5c4c0f28..a681e4d2 100644
--- a/lib/bcoin/protocol/network.js
+++ b/lib/bcoin/protocol/network.js
@@ -21,6 +21,8 @@ network.set = function set(type) {
   utils.merge(network, net);
 };
 
+network.types = ['main', 'testnet', 'regtest', 'segnet'];
+
 /**
  * Main
  */
@@ -139,7 +141,8 @@ main.powNoRetargeting = false;
 main.block = {
   majorityEnforceUpgrade: 750,
   majorityRejectOutdated: 950,
-  majorityWindow: 1000
+  majorityWindow: 1000,
+  bip34height: 227931
 };
 
 main.segwitHeight = 2000000000;
@@ -251,7 +254,8 @@ testnet.powNoRetargeting = false;
 testnet.block = {
   majorityEnforceUpgrade: 51,
   majorityRejectOutdated: 75,
-  majorityWindow: 100
+  majorityWindow: 100,
+  bip34height: 21111
 };
 
 testnet.segwitHeight = 2000000000;
@@ -345,7 +349,8 @@ regtest.powNoRetargeting = true;
 regtest.block = {
   majorityEnforceUpgrade: 750,
   majorityRejectOutdated: 950,
-  majorityWindow: 1000
+  majorityWindow: 1000,
+  bip34height: -1
 };
 
 regtest.segwitHeight = 0;
@@ -437,7 +442,7 @@ segnet.genesis = {
   nonce: 0
 };
 
-segnet.magic = 0x99f57166;
+segnet.magic = 0xcaea962e;
 
 segnet.powLimit = new bn(
   '00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff',
@@ -452,9 +457,28 @@ segnet.powNoRetargeting = false;
 segnet.block = {
   majorityEnforceUpgrade: 7,
   majorityRejectOutdated: 9,
-  majorityWindow: 10
+  majorityWindow: 10,
+  bip34height: -1
 };
 
 segnet.segwitHeight = 0;
 
 segnet.genesisBlock = '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';
+
+network.xprivkeys = {
+  '76066276': 'main',
+  '70615956': 'testnet',
+  '87393172': 'segnet',
+  xprv: 'main',
+  tprv: 'testnet',
+  '2791': 'segnet'
+};
+
+network.xpubkeys = {
+  '76067358': 'main',
+  '70617039': 'testnet',
+  '87394255': 'segnet',
+  xpub: 'main',
+  tpub: 'testnet',
+  '2793': 'segnet'
+};
diff --git a/lib/bcoin/script.js b/lib/bcoin/script.js
index 75ab1ff0..a4a9441b 100644
--- a/lib/bcoin/script.js
+++ b/lib/bcoin/script.js
@@ -393,7 +393,7 @@ script.verify = function verify(input, witness, output, tx, i, flags) {
 };
 
 script.verifyProgram = function verifyProgram(witness, output, tx, i, flags) {
-  var program, witnessScript, script, stack, j;
+  var program, witnessScript, redeem, stack, j;
 
   assert((flags & constants.flags.VERIFY_WITNESS) !== 0);
   assert(script.isWitnessProgram(output));
@@ -433,7 +433,7 @@ script.verifyProgram = function verifyProgram(witness, output, tx, i, flags) {
     if (stack[0].length > 520 || stack[1].length > 520)
       return false;
 
-    script = ['dup', 'hash160', program.data, 'equalverify', 'checksig'];
+    redeem = ['dup', 'hash160', program.data, 'equalverify', 'checksig'];
   } else if (program.type === 'witnessscripthash') {
     if (stack.length === 0)
       return false;
@@ -449,25 +449,31 @@ script.verifyProgram = function verifyProgram(witness, output, tx, i, flags) {
     if (!utils.isEqual(utils.sha256(witnessScript), program.data))
       return false;
 
-    script = script.decode(witnessScript);
+    redeem = script.decode(witnessScript);
   } else {
     assert(false);
   }
 
   for (j = 0; j < stack.length; j++) {
-    if (stack[j].length > constants.script.maxSize)
+    if (stack[j].length > constants.script.maxSize) {
+      throw new Eror('max size');
       return false;
+    }
   }
 
-  res = script.execute(script, stack, tx, i, flags);
+  res = script.execute(redeem, stack, tx, i, flags);
 
   // Verify the script did not fail as well as the stack values
-  if (!res || stack.length === 0 || !script.bool(stack.pop()))
+  if (!res || stack.length === 0 || !script.bool(stack.pop())) {
+    throw new Error('script failed');
     return false;
+  }
 
   // Witnesses always require cleanstack
-  if (stack.length !== 0)
+  if (stack.length !== 0) {
+    throw new Error('cleanstack');
     return false;
+  }
 
   return true;
 };
@@ -1114,12 +1120,12 @@ script.execute = function execute(data, stack, tx, index, flags, recurse) {
             succ++;
         }
 
+        if (stack.length < 1)
+          return false;
+
+        val = stack.pop();
+
         if (flags & constants.flags.VERIFY_NULLDUMMY) {
-          if (stack.length < 1)
-            return false;
-
-          val = stack.pop();
-
           if (!script.isDummy(val))
             return false;
         }
@@ -1975,10 +1981,10 @@ script.isCommitment = function isCommitment(s) {
     && s[0] === 'return'
     && Buffer.isBuffer(s[1])
     && s[1].length === 36
-    && utils.readU32(s[1], 0) === 0xeda921aa24;
+    && utils.readU32BE(s[1], 0) === 0xaa21a9ed;
 };
 
-script.getWitnessRoot = function getWitnessRoot(s) {
+script.getCommitmentHash = function getCommitmentHash(s) {
   if (!script.isCommitment(s))
     return;
 
diff --git a/lib/bcoin/tx.js b/lib/bcoin/tx.js
index a3d7649e..f060899d 100644
--- a/lib/bcoin/tx.js
+++ b/lib/bcoin/tx.js
@@ -114,6 +114,12 @@ TX.prototype.hash = function hash(enc) {
 };
 
 TX.prototype.witnessHash = function witnessHash(enc) {
+  if (this.isCoinbase()) {
+    return enc === 'hex'
+      ? utils.toHex(constants.zeroHash)
+      : new Buffer(constants.zeroHash);
+  }
+
   if (!this._whash)
     this._whash = utils.dsha256(this.renderWitness());
 
@@ -805,6 +811,8 @@ TX.prototype.inspect = function inspect() {
   return {
     type: this.type,
     hash: utils.revHex(this.hash('hex')),
+    witnessHash: utils.revHex(this.witnessHash('hex')),
+    witness: this._witness,
     height: this.height,
     value: utils.btc(this.getValue()),
     fee: utils.btc(this.getFee()),