diff --git a/blockdag/accept.go b/blockdag/accept.go
index 4bbc22e90..8ac923d39 100644
--- a/blockdag/accept.go
+++ b/blockdag/accept.go
@@ -29,7 +29,7 @@ func (dag *BlockDAG) maybeAcceptBlock(block *util.Block, flags BehaviorFlags) er
 	}
 
 	bluestParent := parents.bluest()
-	blockHeight := int32(0)
+	blockHeight := uint64(0)
 	if !block.IsGenesis() {
 		blockHeight = parents.maxHeight() + 1
 	}
diff --git a/blockdag/blocknode.go b/blockdag/blocknode.go
index b7b022fdb..0c4e07ee5 100644
--- a/blockdag/blocknode.go
+++ b/blockdag/blocknode.go
@@ -94,10 +94,10 @@ type blockNode struct {
 	workSum *big.Int
 
 	// height is the position in the block DAG.
-	height int32
+	height uint64
 
 	// chainHeight is the number of hops you need to go down the selected parent chain in order to get to the genesis block.
-	chainHeight uint32
+	chainHeight uint64
 
 	// Some fields from block headers to aid in best chain selection and
 	// reconstructing headers from memory.  These must be treated as
@@ -151,11 +151,11 @@ func initBlockNode(node *blockNode, blockHeader *wire.BlockHeader, parents block
 	}
 }
 
-func calculateNodeHeight(node *blockNode) int32 {
+func calculateNodeHeight(node *blockNode) uint64 {
 	return node.parents.maxHeight() + 1
 }
 
-func calculateChainHeight(node *blockNode) uint32 {
+func calculateChainHeight(node *blockNode) uint64 {
 	if node.isGenesis() {
 		return 0
 	}
@@ -202,7 +202,7 @@ func (node *blockNode) Header() *wire.BlockHeader {
 // that is lower than requested height would be returned.
 //
 // This function is safe for concurrent access.
-func (node *blockNode) SelectedAncestor(height int32) *blockNode {
+func (node *blockNode) SelectedAncestor(height uint64) *blockNode {
 	if height < 0 || height > node.height {
 		return nil
 	}
@@ -220,7 +220,7 @@ func (node *blockNode) SelectedAncestor(height int32) *blockNode {
 // height minus provided distance.
 //
 // This function is safe for concurrent access.
-func (node *blockNode) RelativeAncestor(distance int32) *blockNode {
+func (node *blockNode) RelativeAncestor(distance uint64) *blockNode {
 	return node.SelectedAncestor(node.height - distance)
 }
 
diff --git a/blockdag/blocknode_test.go b/blockdag/blocknode_test.go
index 0eec8a01a..59a83d5b7 100644
--- a/blockdag/blocknode_test.go
+++ b/blockdag/blocknode_test.go
@@ -26,7 +26,7 @@ func TestChainHeight(t *testing.T) {
 
 	tests := []struct {
 		node                *blockNode
-		expectedChainHeight uint32
+		expectedChainHeight uint64
 	}{
 		{
 			node:                node0,
diff --git a/blockdag/blockset.go b/blockdag/blockset.go
index 88e39300a..49c1901aa 100644
--- a/blockdag/blockset.go
+++ b/blockdag/blockset.go
@@ -24,8 +24,8 @@ func setFromSlice(blocks ...*blockNode) blockSet {
 }
 
 // maxHeight returns the height of the highest block in the block set
-func (bs blockSet) maxHeight() int32 {
-	var maxHeight int32
+func (bs blockSet) maxHeight() uint64 {
+	var maxHeight uint64
 	for _, node := range bs {
 		if maxHeight < node.height {
 			maxHeight = node.height
diff --git a/blockdag/checkpoints.go b/blockdag/checkpoints.go
index 2fb6e6533..90bfad893 100644
--- a/blockdag/checkpoints.go
+++ b/blockdag/checkpoints.go
@@ -67,7 +67,7 @@ func (dag *BlockDAG) LatestCheckpoint() *dagconfig.Checkpoint {
 // verifyCheckpoint returns whether the passed block height and hash combination
 // match the checkpoint data.  It also returns true if there is no checkpoint
 // data for the passed block height.
-func (dag *BlockDAG) verifyCheckpoint(height int32, hash *daghash.Hash) bool {
+func (dag *BlockDAG) verifyCheckpoint(height uint64, hash *daghash.Hash) bool {
 	if !dag.HasCheckpoints() {
 		return true
 	}
diff --git a/blockdag/common_test.go b/blockdag/common_test.go
index a8ebbbfea..4eae34cd8 100644
--- a/blockdag/common_test.go
+++ b/blockdag/common_test.go
@@ -47,7 +47,7 @@ func loadBlocks(filename string) (blocks []*util.Block, err error) {
 	var block *util.Block
 
 	err = nil
-	for height := 0; err == nil; height++ {
+	for height := uint64(0); err == nil; height++ {
 		var rintbuf uint32
 		err = binary.Read(dr, binary.LittleEndian, &rintbuf)
 		if err == io.EOF {
@@ -74,7 +74,7 @@ func loadBlocks(filename string) (blocks []*util.Block, err error) {
 		if err != nil {
 			return
 		}
-		block.SetHeight(int32(height))
+		block.SetHeight(height)
 		blocks = append(blocks, block)
 	}
 
@@ -151,7 +151,7 @@ func loadUTXOSet(filename string) (UTXOSet, error) {
 
 // TestSetBlockRewardMaturity makes the ability to set the block reward maturity
 // available when running tests.
-func (dag *BlockDAG) TestSetBlockRewardMaturity(maturity uint16) {
+func (dag *BlockDAG) TestSetBlockRewardMaturity(maturity uint64) {
 	dag.dagParams.BlockRewardMaturity = maturity
 }
 
@@ -174,7 +174,7 @@ func newTestDAG(params *dagconfig.Params) *BlockDAG {
 		timeSource:          NewMedianTime(),
 		minRetargetTimespan: targetTimespan / adjustmentFactor,
 		maxRetargetTimespan: targetTimespan * adjustmentFactor,
-		blocksPerRetarget:   int32(targetTimespan / targetTimePerBlock),
+		blocksPerRetarget:   uint64(targetTimespan / targetTimePerBlock),
 		index:               index,
 		virtual:             newVirtualBlock(setFromSlice(node), params.K),
 		genesis:             index.LookupNode(params.GenesisHash),
diff --git a/blockdag/dag.go b/blockdag/dag.go
index 5962f069a..7118357d1 100644
--- a/blockdag/dag.go
+++ b/blockdag/dag.go
@@ -63,7 +63,7 @@ type BlockDAG struct {
 	// be changed afterwards, so there is no need to protect them with a
 	// separate mutex.
 	checkpoints         []dagconfig.Checkpoint
-	checkpointsByHeight map[int32]*dagconfig.Checkpoint
+	checkpointsByHeight map[uint64]*dagconfig.Checkpoint
 	db                  database.DB
 	dagParams           *dagconfig.Params
 	timeSource          MedianTimeSource
@@ -75,9 +75,9 @@ type BlockDAG struct {
 	// parameters.  They are also set when the instance is created and
 	// can't be changed afterwards, so there is no need to protect them with
 	// a separate mutex.
-	minRetargetTimespan int64 // target timespan / adjustment factor
-	maxRetargetTimespan int64 // target timespan * adjustment factor
-	blocksPerRetarget   int32 // target timespan / target time per block
+	minRetargetTimespan int64  // target timespan / adjustment factor
+	maxRetargetTimespan int64  // target timespan * adjustment factor
+	blocksPerRetarget   uint64 // target timespan / target time per block
 
 	// dagLock protects concurrent access to the vast majority of the
 	// fields in this struct below this point.
@@ -333,7 +333,7 @@ func (dag *BlockDAG) addOrphanBlock(block *util.Block) {
 // 'BlockHeight' has been reached.
 type SequenceLock struct {
 	Seconds     int64
-	BlockHeight int32
+	BlockHeight int64
 }
 
 // CalcSequenceLock computes a relative lock-time SequenceLock for the passed
@@ -440,7 +440,7 @@ func (dag *BlockDAG) calcSequenceLock(node *blockNode, utxoSet UTXOSet, tx *util
 			// the input's height as its converted absolute
 			// lock-time. We subtract one from the relative lock in
 			// order to maintain the original lockTime semantics.
-			blockHeight := inputHeight + int32(relativeLock-1)
+			blockHeight := int64(inputHeight) + relativeLock - 1
 			if blockHeight > sequenceLock.BlockHeight {
 				sequenceLock.BlockHeight = blockHeight
 			}
@@ -1131,7 +1131,7 @@ func (dag *BlockDAG) IsInSelectedPathChain(blockHash *daghash.Hash) bool {
 }
 
 // Height returns the height of the highest tip in the DAG
-func (dag *BlockDAG) Height() int32 {
+func (dag *BlockDAG) Height() uint64 {
 	return dag.virtual.tips().maxHeight()
 }
 
@@ -1231,10 +1231,10 @@ func (dag *BlockDAG) blockLocator(node *blockNode) BlockLocator {
 
 	// Requested hash itself + genesis block.
 	// Then floor(log2(height-10)) entries for the skip portion.
-	maxEntries := 2 + util.FastLog2Floor(uint32(node.height))
+	maxEntries := 2 + util.FastLog2Floor(node.height)
 	locator := make(BlockLocator, 0, maxEntries)
 
-	step := int32(1)
+	step := uint64(1)
 	for node != nil {
 		locator = append(locator, node.hash)
 
@@ -1264,7 +1264,7 @@ func (dag *BlockDAG) blockLocator(node *blockNode) BlockLocator {
 // DAG.
 //
 // This function is safe for concurrent access.
-func (dag *BlockDAG) BlockHeightByHash(hash *daghash.Hash) (int32, error) {
+func (dag *BlockDAG) BlockHeightByHash(hash *daghash.Hash) (uint64, error) {
 	node := dag.index.LookupNode(hash)
 	if node == nil {
 		str := fmt.Sprintf("block %s is not in the DAG", hash)
@@ -1295,7 +1295,7 @@ func (dag *BlockDAG) ChildHashesByHash(hash *daghash.Hash) ([]*daghash.Hash, err
 // end hash must belong to a block that is known to be valid.
 //
 // This function is safe for concurrent access.
-func (dag *BlockDAG) HeightToHashRange(startHeight int32,
+func (dag *BlockDAG) HeightToHashRange(startHeight uint64,
 	endHash *daghash.Hash, maxResults int) ([]*daghash.Hash, error) {
 
 	endNode := dag.index.LookupNode(endHash)
@@ -1335,7 +1335,7 @@ func (dag *BlockDAG) HeightToHashRange(startHeight int32,
 // endHash where the block height is a positive multiple of interval.
 //
 // This function is safe for concurrent access.
-func (dag *BlockDAG) IntervalBlockHashes(endHash *daghash.Hash, interval int,
+func (dag *BlockDAG) IntervalBlockHashes(endHash *daghash.Hash, interval uint64,
 ) ([]*daghash.Hash, error) {
 
 	endNode := dag.index.LookupNode(endHash)
@@ -1347,15 +1347,15 @@ func (dag *BlockDAG) IntervalBlockHashes(endHash *daghash.Hash, interval int,
 	}
 	endHeight := endNode.height
 
-	resultsLength := int(endHeight) / interval
+	resultsLength := endHeight / interval
 	hashes := make([]*daghash.Hash, resultsLength)
 
 	dag.virtual.mtx.Lock()
 	defer dag.virtual.mtx.Unlock()
 
 	blockNode := endNode
-	for index := int(endHeight) / interval; index > 0; index-- {
-		blockHeight := int32(index * interval)
+	for index := endHeight / interval; index > 0; index-- {
+		blockHeight := index * interval
 		blockNode = blockNode.SelectedAncestor(blockHeight)
 
 		hashes[index-1] = blockNode.hash
@@ -1654,10 +1654,10 @@ func New(config *Config) (*BlockDAG, error) {
 
 	// Generate a checkpoint by height map from the provided checkpoints
 	// and assert the provided checkpoints are sorted by height as required.
-	var checkpointsByHeight map[int32]*dagconfig.Checkpoint
-	var prevCheckpointHeight int32
+	var checkpointsByHeight map[uint64]*dagconfig.Checkpoint
+	var prevCheckpointHeight uint64
 	if len(config.Checkpoints) > 0 {
-		checkpointsByHeight = make(map[int32]*dagconfig.Checkpoint)
+		checkpointsByHeight = make(map[uint64]*dagconfig.Checkpoint)
 		for i := range config.Checkpoints {
 			checkpoint := &config.Checkpoints[i]
 			if checkpoint.Height <= prevCheckpointHeight {
@@ -1685,7 +1685,7 @@ func New(config *Config) (*BlockDAG, error) {
 		indexManager:        config.IndexManager,
 		minRetargetTimespan: targetTimespan / adjustmentFactor,
 		maxRetargetTimespan: targetTimespan * adjustmentFactor,
-		blocksPerRetarget:   int32(targetTimespan / targetTimePerBlock),
+		blocksPerRetarget:   uint64(targetTimespan / targetTimePerBlock),
 		index:               index,
 		virtual:             newVirtualBlock(nil, params.K),
 		orphans:             make(map[daghash.Hash]*orphanBlock),
diff --git a/blockdag/dag_test.go b/blockdag/dag_test.go
index fd5928d7e..8afd7daba 100644
--- a/blockdag/dag_test.go
+++ b/blockdag/dag_test.go
@@ -231,8 +231,8 @@ func TestCalcSequenceLock(t *testing.T) {
 	dag := newTestDAG(netParams)
 	node := dag.selectedTip()
 	blockTime := node.Header().Timestamp
-	numBlocksToGenerate := uint32(5)
-	for i := uint32(0); i < numBlocksToGenerate; i++ {
+	numBlocksToGenerate := 5
+	for i := 0; i < numBlocksToGenerate; i++ {
 		blockTime = blockTime.Add(time.Second)
 		node = newTestNode(setFromSlice(node), blockVersion, 0, blockTime, netParams.K)
 		dag.index.AddNode(node)
@@ -245,7 +245,7 @@ func TestCalcSequenceLock(t *testing.T) {
 	msgTx := wire.NewNativeMsgTx(wire.TxVersion, nil, []*wire.TxOut{{PkScript: nil, Value: 10}})
 	targetTx := util.NewTx(msgTx)
 	utxoSet := NewFullUTXOSet()
-	utxoSet.AddTx(targetTx.MsgTx(), int32(numBlocksToGenerate)-4)
+	utxoSet.AddTx(targetTx.MsgTx(), uint64(numBlocksToGenerate)-4)
 
 	// Create a utxo that spends the fake utxo created above for use in the
 	// transactions created in the tests.  It has an age of 4 blocks.  Note
@@ -256,7 +256,7 @@ func TestCalcSequenceLock(t *testing.T) {
 		TxID:  *targetTx.ID(),
 		Index: 0,
 	}
-	prevUtxoHeight := int32(numBlocksToGenerate) - 4
+	prevUtxoHeight := uint64(numBlocksToGenerate) - 4
 
 	// Obtain the median time past from the PoV of the input created above.
 	// The MTP for the input is the MTP from the PoV of the block *prior*
@@ -348,7 +348,7 @@ func TestCalcSequenceLock(t *testing.T) {
 			utxoSet: utxoSet,
 			want: &SequenceLock{
 				Seconds:     medianTime + (5 << wire.SequenceLockTimeGranularity) - 1,
-				BlockHeight: prevUtxoHeight + 3,
+				BlockHeight: int64(prevUtxoHeight) + 3,
 			},
 		},
 		// Transaction with a single input.  The input's sequence number
@@ -360,7 +360,7 @@ func TestCalcSequenceLock(t *testing.T) {
 			utxoSet: utxoSet,
 			want: &SequenceLock{
 				Seconds:     -1,
-				BlockHeight: prevUtxoHeight + 2,
+				BlockHeight: int64(prevUtxoHeight) + 2,
 			},
 		},
 		// A transaction with two inputs with lock times expressed in
@@ -397,7 +397,7 @@ func TestCalcSequenceLock(t *testing.T) {
 			utxoSet: utxoSet,
 			want: &SequenceLock{
 				Seconds:     -1,
-				BlockHeight: prevUtxoHeight + 10,
+				BlockHeight: int64(prevUtxoHeight) + 10,
 			},
 		},
 		// A transaction with multiple inputs.  Two inputs are time
@@ -422,7 +422,7 @@ func TestCalcSequenceLock(t *testing.T) {
 			utxoSet: utxoSet,
 			want: &SequenceLock{
 				Seconds:     medianTime + (13 << wire.SequenceLockTimeGranularity) - 1,
-				BlockHeight: prevUtxoHeight + 8,
+				BlockHeight: int64(prevUtxoHeight) + 8,
 			},
 		},
 		// A transaction with a single unconfirmed input.  As the input
@@ -437,7 +437,7 @@ func TestCalcSequenceLock(t *testing.T) {
 			mempool: true,
 			want: &SequenceLock{
 				Seconds:     -1,
-				BlockHeight: nextBlockHeight + 1,
+				BlockHeight: int64(nextBlockHeight) + 1,
 			},
 		},
 		// A transaction with a single unconfirmed input.  The input has
@@ -587,7 +587,7 @@ func TestHeightToHashRange(t *testing.T) {
 
 	tests := []struct {
 		name        string
-		startHeight int32           // locator for requested inventory
+		startHeight uint64          // locator for requested inventory
 		endHash     *daghash.Hash   // stop hash for locator
 		maxResults  int             // max to locate, 0 = wire const
 		hashes      []*daghash.Hash // expected located hashes
@@ -680,7 +680,7 @@ func TestIntervalBlockHashes(t *testing.T) {
 	tests := []struct {
 		name        string
 		endHash     *daghash.Hash
-		interval    int
+		interval    uint64
 		hashes      []*daghash.Hash
 		expectError bool
 	}{
diff --git a/blockdag/dagio.go b/blockdag/dagio.go
index 68efa3186..02109320e 100644
--- a/blockdag/dagio.go
+++ b/blockdag/dagio.go
@@ -292,7 +292,7 @@ func deserializeUTXOEntry(serialized []byte) (*UTXOEntry, error) {
 	// Bit 0 indicates whether the containing transaction is a block reward.
 	// Bits 1-x encode height of containing transaction.
 	isBlockReward := code&0x01 != 0
-	blockHeight := int32(code >> 1)
+	blockHeight := code >> 1
 
 	// Decode the compressed unspent transaction output.
 	amount, pkScript, _, err := decodeCompressedTxOut(serialized[offset:])
@@ -371,10 +371,10 @@ func dbPutUTXODiff(dbTx database.Tx, diff *UTXODiff) error {
 // dbPutBlockIndex uses an existing database transaction to update or add the
 // block index entries for the hash to height and height to hash mappings for
 // the provided values.
-func dbPutBlockIndex(dbTx database.Tx, hash *daghash.Hash, height int32) error {
+func dbPutBlockIndex(dbTx database.Tx, hash *daghash.Hash, height uint64) error {
 	// Serialize the height for use in the index entries.
-	var serializedHeight [4]byte
-	byteOrder.PutUint32(serializedHeight[:], uint32(height))
+	var serializedHeight [8]byte
+	byteOrder.PutUint64(serializedHeight[:], height)
 
 	// Add the block hash to height mapping to the index.
 	meta := dbTx.Metadata()
diff --git a/blockdag/fullblocktests/generate.go b/blockdag/fullblocktests/generate.go
index 6375cada4..7803c6a58 100644
--- a/blockdag/fullblocktests/generate.go
+++ b/blockdag/fullblocktests/generate.go
@@ -67,7 +67,7 @@ type TestInstance interface {
 type AcceptedBlock struct {
 	Name     string
 	Block    *wire.MsgBlock
-	Height   int32
+	Height   uint64
 	IsOrphan bool
 }
 
@@ -85,7 +85,7 @@ func (b AcceptedBlock) FullBlockTestInstance() {}
 type RejectedBlock struct {
 	Name       string
 	Block      *wire.MsgBlock
-	Height     int32
+	Height     uint64
 	RejectCode blockdag.ErrorCode
 }
 
@@ -107,7 +107,7 @@ func (b RejectedBlock) FullBlockTestInstance() {}
 type OrphanOrRejectedBlock struct {
 	Name   string
 	Block  *wire.MsgBlock
-	Height int32
+	Height uint64
 }
 
 // Ensure ExpectedTip implements the TestInstance interface.
@@ -124,7 +124,7 @@ func (b OrphanOrRejectedBlock) FullBlockTestInstance() {}
 type ExpectedTip struct {
 	Name   string
 	Block  *wire.MsgBlock
-	Height int32
+	Height uint64
 }
 
 // Ensure ExpectedTip implements the TestInstance interface.
@@ -141,7 +141,7 @@ func (b ExpectedTip) FullBlockTestInstance() {}
 type RejectedNonCanonicalBlock struct {
 	Name     string
 	RawBlock []byte
-	Height   int32
+	Height   uint64
 }
 
 // FullBlockTestInstance only exists to allow RejectedNonCanonicalBlock to be treated as
@@ -182,10 +182,10 @@ type testGenerator struct {
 	params       *dagconfig.Params
 	tip          *wire.MsgBlock
 	tipName      string
-	tipHeight    int32
+	tipHeight    uint64
 	blocks       map[daghash.Hash]*wire.MsgBlock
 	blocksByName map[string]*wire.MsgBlock
-	blockHeights map[string]int32
+	blockHeights map[string]uint64
 
 	// Used for tracking spendable coinbase outputs.
 	spendableOuts     []spendableOut
@@ -205,7 +205,7 @@ func makeTestGenerator(params *dagconfig.Params) (testGenerator, error) {
 		params:       params,
 		blocks:       map[daghash.Hash]*wire.MsgBlock{*genesisHash: genesis},
 		blocksByName: map[string]*wire.MsgBlock{"genesis": genesis},
-		blockHeights: map[string]int32{"genesis": 0},
+		blockHeights: map[string]uint64{"genesis": 0},
 		tip:          genesis,
 		tipName:      "genesis",
 		tipHeight:    0,
@@ -243,7 +243,7 @@ func pushDataScript(items ...[]byte) []byte {
 // standardCoinbaseScript returns a standard script suitable for use as the
 // signature script of the coinbase transaction of a new block.  In particular,
 // it starts with the block height that is required by version 2 blocks.
-func standardCoinbaseScript(blockHeight int32, extraNonce uint64) ([]byte, error) {
+func standardCoinbaseScript(blockHeight uint64, extraNonce uint64) ([]byte, error) {
 	return txscript.NewScriptBuilder().AddInt64(int64(blockHeight)).
 		AddInt64(int64(extraNonce)).Script()
 }
@@ -275,7 +275,7 @@ func uniqueOpReturnScript() []byte {
 // createCoinbaseTx returns a coinbase transaction paying an appropriate
 // subsidy based on the passed block height.  The coinbase signature script
 // conforms to the requirements of version 2 blocks.
-func (g *testGenerator) createCoinbaseTx(blockHeight int32) *wire.MsgTx {
+func (g *testGenerator) createCoinbaseTx(blockHeight uint64) *wire.MsgTx {
 	extraNonce := uint64(0)
 	coinbaseScript, err := standardCoinbaseScript(blockHeight, extraNonce)
 	if err != nil {
@@ -912,7 +912,7 @@ func Generate(includeLargeReorg bool) (tests [][]TestInstance, err error) {
 
 	coinbaseMaturity := g.params.BlockRewardMaturity
 	var testInstances []TestInstance
-	for i := uint16(0); i < coinbaseMaturity; i++ {
+	for i := uint64(0); i < coinbaseMaturity; i++ {
 		blockName := fmt.Sprintf("bm%d", i)
 		g.nextBlock(blockName, nil)
 		g.saveTipCoinbaseOut()
@@ -923,7 +923,7 @@ func Generate(includeLargeReorg bool) (tests [][]TestInstance, err error) {
 
 	// Collect spendable outputs.  This simplifies the code below.
 	var outs []*spendableOut
-	for i := uint16(0); i < coinbaseMaturity; i++ {
+	for i := uint64(0); i < coinbaseMaturity; i++ {
 		op := g.oldestCoinbaseOut()
 		outs = append(outs, &op)
 	}
@@ -2059,7 +2059,7 @@ func Generate(includeLargeReorg bool) (tests [][]TestInstance, err error) {
 	// Collect all of the spendable coinbase outputs from the previous
 	// collection point up to the current tip.
 	g.saveSpendableCoinbaseOuts()
-	spendableOutOffset := g.tipHeight - int32(coinbaseMaturity)
+	spendableOutOffset := g.tipHeight - coinbaseMaturity
 
 	// Extend the main chain by a large number of max size blocks.
 	//
@@ -2068,7 +2068,7 @@ func Generate(includeLargeReorg bool) (tests [][]TestInstance, err error) {
 	reorgSpend := *outs[spendableOutOffset]
 	reorgStartBlockName := g.tipName
 	chain1TipName := g.tipName
-	for i := int32(0); i < numLargeReorgBlocks; i++ {
+	for i := uint64(0); i < numLargeReorgBlocks; i++ {
 		chain1TipName = fmt.Sprintf("br%d", i)
 		g.nextBlock(chain1TipName, &reorgSpend, func(b *wire.MsgBlock) {
 			bytesToMaxSize := maxBlockSize - b.SerializeSize() - 3
@@ -2083,7 +2083,7 @@ func Generate(includeLargeReorg bool) (tests [][]TestInstance, err error) {
 		// Use the next available spendable output.  First use up any
 		// remaining spendable outputs that were already popped into the
 		// outs slice, then just pop them from the stack.
-		if spendableOutOffset+1+i < int32(len(outs)) {
+		if spendableOutOffset+1+i < uint64(len(outs)) {
 			reorgSpend = *outs[spendableOutOffset+1+i]
 		} else {
 			reorgSpend = g.oldestCoinbaseOut()
diff --git a/blockdag/test_utils.go b/blockdag/test_utils.go
index f3cd6d778..e22696bf2 100644
--- a/blockdag/test_utils.go
+++ b/blockdag/test_utils.go
@@ -140,7 +140,7 @@ func createTxForTest(numInputs uint32, numOutputs uint32, outputValue uint64, su
 // outputs paying an appropriate subsidy based on the passed block height to the
 // address associated with the harness.  It automatically uses a standard
 // signature script that starts with the block height
-func createCoinbaseTxForTest(blockHeight int32, numOutputs uint32, extraNonce int64, params *dagconfig.Params) (*wire.MsgTx, error) {
+func createCoinbaseTxForTest(blockHeight uint64, numOutputs uint32, extraNonce int64, params *dagconfig.Params) (*wire.MsgTx, error) {
 	// Create standard coinbase script.
 	coinbaseScript, err := txscript.NewScriptBuilder().
 		AddInt64(int64(blockHeight)).AddInt64(extraNonce).Script()
diff --git a/blockdag/thresholdstate.go b/blockdag/thresholdstate.go
index 6875cbb0e..7c4358f9a 100644
--- a/blockdag/thresholdstate.go
+++ b/blockdag/thresholdstate.go
@@ -77,11 +77,11 @@ type thresholdConditionChecker interface {
 
 	// RuleChangeActivationThreshold is the number of blocks for which the
 	// condition must be true in order to lock in a rule change.
-	RuleChangeActivationThreshold() uint32
+	RuleChangeActivationThreshold() uint64
 
 	// MinerConfirmationWindow is the number of blocks in each threshold
 	// state retarget window.
-	MinerConfirmationWindow() uint32
+	MinerConfirmationWindow() uint64
 
 	// Condition returns whether or not the rule change activation condition
 	// has been met.  This typically involves checking whether or not the
@@ -129,7 +129,7 @@ func newThresholdCaches(numCaches uint32) []thresholdStateCache {
 func (dag *BlockDAG) thresholdState(prevNode *blockNode, checker thresholdConditionChecker, cache *thresholdStateCache) (ThresholdState, error) {
 	// The threshold state for the window that contains the genesis block is
 	// defined by definition.
-	confirmationWindow := int32(checker.MinerConfirmationWindow())
+	confirmationWindow := checker.MinerConfirmationWindow()
 	if prevNode == nil || (prevNode.height+1) < confirmationWindow {
 		return ThresholdDefined, nil
 	}
@@ -218,9 +218,9 @@ func (dag *BlockDAG) thresholdState(prevNode *blockNode, checker thresholdCondit
 			// At this point, the rule change is still being voted
 			// on by the miners, so iterate backwards through the
 			// confirmation window to count all of the votes in it.
-			var count uint32
+			var count uint64
 			countNode := prevNode
-			for i := int32(0); i < confirmationWindow; i++ {
+			for i := uint64(0); i < confirmationWindow; i++ {
 				condition, err := checker.Condition(countNode)
 				if err != nil {
 					return ThresholdFailed, err
diff --git a/blockdag/utxoset.go b/blockdag/utxoset.go
index 95ba39ffd..7f3bf9b4f 100644
--- a/blockdag/utxoset.go
+++ b/blockdag/utxoset.go
@@ -22,7 +22,7 @@ type UTXOEntry struct {
 
 	amount      uint64
 	pkScript    []byte // The public key script for the output.
-	blockHeight int32  // Height of block containing tx.
+	blockHeight uint64 // Height of block containing tx.
 
 	// packedFlags contains additional info about output such as whether it
 	// is a block reward, and whether it has been modified
@@ -38,7 +38,7 @@ func (entry *UTXOEntry) IsBlockReward() bool {
 }
 
 // BlockHeight returns the height of the block containing the output.
-func (entry *UTXOEntry) BlockHeight() int32 {
+func (entry *UTXOEntry) BlockHeight() uint64 {
 	return entry.blockHeight
 }
 
@@ -305,7 +305,7 @@ func (d UTXODiff) String() string {
 }
 
 // NewUTXOEntry creates a new utxoEntry representing the given txOut
-func NewUTXOEntry(txOut *wire.TxOut, isBlockReward bool, blockHeight int32) *UTXOEntry {
+func NewUTXOEntry(txOut *wire.TxOut, isBlockReward bool, blockHeight uint64) *UTXOEntry {
 	entry := &UTXOEntry{
 		amount:      txOut.Value,
 		pkScript:    txOut.PkScript,
@@ -336,7 +336,7 @@ type UTXOSet interface {
 	diffFrom(other UTXOSet) (*UTXODiff, error)
 	WithDiff(utxoDiff *UTXODiff) (UTXOSet, error)
 	diffFromTx(tx *wire.MsgTx, node *blockNode) (*UTXODiff, error)
-	AddTx(tx *wire.MsgTx, blockHeight int32) (ok bool)
+	AddTx(tx *wire.MsgTx, blockHeight uint64) (ok bool)
 	clone() UTXOSet
 	Get(outPoint wire.OutPoint) (*UTXOEntry, bool)
 }
@@ -401,7 +401,7 @@ func (fus *FullUTXOSet) WithDiff(other *UTXODiff) (UTXOSet, error) {
 }
 
 // AddTx adds a transaction to this utxoSet and returns true iff it's valid in this UTXO's context
-func (fus *FullUTXOSet) AddTx(tx *wire.MsgTx, blockHeight int32) bool {
+func (fus *FullUTXOSet) AddTx(tx *wire.MsgTx, blockHeight uint64) bool {
 	isBlockReward := tx.IsBlockReward()
 	if !isBlockReward {
 		if !fus.containsInputs(tx) {
@@ -493,7 +493,7 @@ func (dus *DiffUTXOSet) WithDiff(other *UTXODiff) (UTXOSet, error) {
 }
 
 // AddTx adds a transaction to this utxoSet and returns true iff it's valid in this UTXO's context
-func (dus *DiffUTXOSet) AddTx(tx *wire.MsgTx, blockHeight int32) bool {
+func (dus *DiffUTXOSet) AddTx(tx *wire.MsgTx, blockHeight uint64) bool {
 	isBlockReward := tx.IsBlockReward()
 	if !isBlockReward && !dus.containsInputs(tx) {
 		return false
@@ -504,7 +504,7 @@ func (dus *DiffUTXOSet) AddTx(tx *wire.MsgTx, blockHeight int32) bool {
 	return true
 }
 
-func (dus *DiffUTXOSet) appendTx(tx *wire.MsgTx, blockHeight int32, isBlockReward bool) {
+func (dus *DiffUTXOSet) appendTx(tx *wire.MsgTx, blockHeight uint64, isBlockReward bool) {
 	if !isBlockReward {
 
 		for _, txIn := range tx.TxIn {
diff --git a/blockdag/utxoset_test.go b/blockdag/utxoset_test.go
index 0b8c78e6f..7f1726130 100644
--- a/blockdag/utxoset_test.go
+++ b/blockdag/utxoset_test.go
@@ -663,7 +663,7 @@ func TestDiffUTXOSet_addTx(t *testing.T) {
 	tests := []struct {
 		name        string
 		startSet    *DiffUTXOSet
-		startHeight int32
+		startHeight uint64
 		toAdd       []*wire.MsgTx
 		expectedSet *DiffUTXOSet
 	}{
@@ -776,7 +776,7 @@ func TestDiffUTXOSet_addTx(t *testing.T) {
 
 		// Apply all transactions to diffSet, in order, with the initial block height startHeight
 		for i, transaction := range test.toAdd {
-			diffSet.AddTx(transaction, test.startHeight+int32(i))
+			diffSet.AddTx(transaction, test.startHeight+uint64(i))
 		}
 
 		// Make sure that the result diffSet equals to the expectedSet
diff --git a/blockdag/validate.go b/blockdag/validate.go
index 043d3d6ae..7dae024eb 100644
--- a/blockdag/validate.go
+++ b/blockdag/validate.go
@@ -83,14 +83,14 @@ func IsFeeTransaction(tx *util.Tx) bool {
 // SequenceLockActive determines if a transaction's sequence locks have been
 // met, meaning that all the inputs of a given transaction have reached a
 // height or time sufficient for their relative lock-time maturity.
-func SequenceLockActive(sequenceLock *SequenceLock, blockHeight int32,
+func SequenceLockActive(sequenceLock *SequenceLock, blockHeight uint64,
 	medianTimePast time.Time) bool {
 
 	// If either the seconds, or height relative-lock time has not yet
 	// reached, then the transaction is not yet mature according to its
 	// sequence locks.
 	if sequenceLock.Seconds >= medianTimePast.Unix() ||
-		sequenceLock.BlockHeight >= blockHeight {
+		sequenceLock.BlockHeight >= int64(blockHeight) {
 		return false
 	}
 
@@ -98,7 +98,7 @@ func SequenceLockActive(sequenceLock *SequenceLock, blockHeight int32,
 }
 
 // IsFinalizedTransaction determines whether or not a transaction is finalized.
-func IsFinalizedTransaction(tx *util.Tx, blockHeight int32, blockTime time.Time) bool {
+func IsFinalizedTransaction(tx *util.Tx, blockHeight uint64, blockTime time.Time) bool {
 	msgTx := tx.MsgTx()
 
 	// Lock time of zero means the transaction is finalized.
@@ -142,7 +142,7 @@ func IsFinalizedTransaction(tx *util.Tx, blockHeight int32, blockTime time.Time)
 //
 // At the target block generation rate for the main network, this is
 // approximately every 4 years.
-func CalcBlockSubsidy(height int32, dagParams *dagconfig.Params) uint64 {
+func CalcBlockSubsidy(height uint64, dagParams *dagconfig.Params) uint64 {
 	if dagParams.SubsidyReductionInterval == 0 {
 		return baseSubsidy
 	}
@@ -615,7 +615,7 @@ func (dag *BlockDAG) CheckBlockSanity(block *util.Block, powLimit *big.Int,
 
 // ExtractCoinbaseHeight attempts to extract the height of the block from the
 // scriptSig of a coinbase transaction.
-func ExtractCoinbaseHeight(coinbaseTx *util.Tx) (int32, error) {
+func ExtractCoinbaseHeight(coinbaseTx *util.Tx) (uint64, error) {
 	sigScript := coinbaseTx.MsgTx().TxIn[0].SignatureScript
 	if len(sigScript) < 1 {
 		str := "the coinbase signature script" +
@@ -631,7 +631,7 @@ func ExtractCoinbaseHeight(coinbaseTx *util.Tx) (int32, error) {
 		return 0, nil
 	}
 	if opcode >= txscript.Op1 && opcode <= txscript.Op16 {
-		return int32(opcode - (txscript.Op1 - 1)), nil
+		return uint64(opcode - (txscript.Op1 - 1)), nil
 	}
 
 	// Otherwise, the opcode is the length of the following bytes which
@@ -648,7 +648,7 @@ func ExtractCoinbaseHeight(coinbaseTx *util.Tx) (int32, error) {
 	copy(serializedHeightBytes, sigScript[1:serializedLen+1])
 	serializedHeight := binary.LittleEndian.Uint64(serializedHeightBytes)
 
-	return int32(serializedHeight), nil
+	return serializedHeight, nil
 }
 
 // checkSerializedHeight checks if the signature script in the passed
@@ -678,7 +678,7 @@ func checkSerializedHeight(block *util.Block) error {
 //    the checkpoints are not performed.
 //
 // This function MUST be called with the dag state lock held (for writes).
-func (dag *BlockDAG) checkBlockHeaderContext(header *wire.BlockHeader, bluestParent *blockNode, blockHeight int32, fastAdd bool) error {
+func (dag *BlockDAG) checkBlockHeaderContext(header *wire.BlockHeader, bluestParent *blockNode, blockHeight uint64, fastAdd bool) error {
 	if !fastAdd {
 		if err := dag.validateDifficulty(header, bluestParent); err != nil {
 			return err
@@ -692,7 +692,7 @@ func (dag *BlockDAG) checkBlockHeaderContext(header *wire.BlockHeader, bluestPar
 	return dag.validateCheckpoints(header, blockHeight)
 }
 
-func (dag *BlockDAG) validateCheckpoints(header *wire.BlockHeader, blockHeight int32) error {
+func (dag *BlockDAG) validateCheckpoints(header *wire.BlockHeader, blockHeight uint64) error {
 	// Ensure dag matches up to predetermined checkpoints.
 	blockHash := header.BlockHash()
 	if !dag.verifyCheckpoint(blockHeight, blockHash) {
@@ -753,7 +753,7 @@ func (dag *BlockDAG) validateDifficulty(header *wire.BlockHeader, bluestParent *
 
 // validateParents validates that no parent is an ancestor of another parent
 func validateParents(blockHeader *wire.BlockHeader, parents blockSet) error {
-	minHeight := int32(math.MaxInt32)
+	minHeight := uint64(math.MaxUint64)
 	queue := newDownHeap()
 	visited := newSet()
 	for _, parent := range parents {
@@ -895,7 +895,7 @@ func ensureNoDuplicateTx(block *blockNode, utxoSet UTXOSet,
 //
 // NOTE: The transaction MUST have already been sanity checked with the
 // CheckTransactionSanity function prior to calling this function.
-func CheckTransactionInputsAndCalulateFee(tx *util.Tx, txHeight int32, utxoSet UTXOSet, dagParams *dagconfig.Params, fastAdd bool) (
+func CheckTransactionInputsAndCalulateFee(tx *util.Tx, txHeight uint64, utxoSet UTXOSet, dagParams *dagconfig.Params, fastAdd bool) (
 	txFeeInSatoshi uint64, err error) {
 
 	// Block reward transactions (a.k.a. coinbase or fee transactions)
@@ -976,20 +976,19 @@ func CheckTransactionInputsAndCalulateFee(tx *util.Tx, txHeight int32, utxoSet U
 	return txFeeInSatoshi, nil
 }
 
-func validateBlockRewardMaturity(dagParams *dagconfig.Params, entry *UTXOEntry, txHeight int32, txIn *wire.TxIn) error {
+func validateBlockRewardMaturity(dagParams *dagconfig.Params, entry *UTXOEntry, txHeight uint64, txIn *wire.TxIn) error {
 	// Ensure the transaction is not spending coins which have not
 	// yet reached the required block reward maturity.
 	if entry.IsBlockReward() {
 		originHeight := entry.BlockHeight()
 		blocksSincePrev := txHeight - originHeight
-		blockRewardMaturity := int32(dagParams.BlockRewardMaturity)
-		if blocksSincePrev < blockRewardMaturity {
+		if blocksSincePrev < dagParams.BlockRewardMaturity {
 			str := fmt.Sprintf("tried to spend block reward "+
 				"transaction output %s from height %d "+
 				"at height %d before required maturity "+
 				"of %d blocks", txIn.PreviousOutPoint,
 				originHeight, txHeight,
-				blockRewardMaturity)
+				dagParams.BlockRewardMaturity)
 			return ruleError(ErrImmatureSpend, str)
 		}
 	}
diff --git a/blockdag/validate_test.go b/blockdag/validate_test.go
index 5731ecad5..67e4a19e3 100644
--- a/blockdag/validate_test.go
+++ b/blockdag/validate_test.go
@@ -20,7 +20,7 @@ import (
 // TestSequenceLocksActive tests the SequenceLockActive function to ensure it
 // works as expected in all possible combinations/scenarios.
 func TestSequenceLocksActive(t *testing.T) {
-	seqLock := func(h int32, s int64) *SequenceLock {
+	seqLock := func(h int64, s int64) *SequenceLock {
 		return &SequenceLock{
 			Seconds:     s,
 			BlockHeight: h,
@@ -29,7 +29,7 @@ func TestSequenceLocksActive(t *testing.T) {
 
 	tests := []struct {
 		seqLock     *SequenceLock
-		blockHeight int32
+		blockHeight uint64
 		mtp         time.Time
 
 		want bool
@@ -488,7 +488,7 @@ func TestCheckSerializedHeight(t *testing.T) {
 
 	tests := []struct {
 		sigScript  []byte // Serialized data
-		wantHeight int32  // Expected height
+		wantHeight uint64 // Expected height
 		err        error  // Expected error type
 	}{
 		// No serialized height length.
diff --git a/blockdag/versionbits.go b/blockdag/versionbits.go
index 924803f6c..34b3c70ef 100644
--- a/blockdag/versionbits.go
+++ b/blockdag/versionbits.go
@@ -78,7 +78,7 @@ func (c bitConditionChecker) EndTime() uint64 {
 // is associated with.
 //
 // This is part of the thresholdConditionChecker interface implementation.
-func (c bitConditionChecker) RuleChangeActivationThreshold() uint32 {
+func (c bitConditionChecker) RuleChangeActivationThreshold() uint64 {
 	return c.chain.dagParams.RuleChangeActivationThreshold
 }
 
@@ -89,7 +89,7 @@ func (c bitConditionChecker) RuleChangeActivationThreshold() uint32 {
 // is associated with.
 //
 // This is part of the thresholdConditionChecker interface implementation.
-func (c bitConditionChecker) MinerConfirmationWindow() uint32 {
+func (c bitConditionChecker) MinerConfirmationWindow() uint64 {
 	return c.chain.dagParams.MinerConfirmationWindow
 }
 
@@ -159,7 +159,7 @@ func (c deploymentChecker) EndTime() uint64 {
 // is associated with.
 //
 // This is part of the thresholdConditionChecker interface implementation.
-func (c deploymentChecker) RuleChangeActivationThreshold() uint32 {
+func (c deploymentChecker) RuleChangeActivationThreshold() uint64 {
 	return c.chain.dagParams.RuleChangeActivationThreshold
 }
 
@@ -170,7 +170,7 @@ func (c deploymentChecker) RuleChangeActivationThreshold() uint32 {
 // is associated with.
 //
 // This is part of the thresholdConditionChecker interface implementation.
-func (c deploymentChecker) MinerConfirmationWindow() uint32 {
+func (c deploymentChecker) MinerConfirmationWindow() uint64 {
 	return c.chain.dagParams.MinerConfirmationWindow
 }
 
@@ -250,7 +250,7 @@ func (dag *BlockDAG) warnUnknownRuleActivations(node *blockNode) error {
 			}
 
 		case ThresholdLockedIn:
-			window := int32(checker.MinerConfirmationWindow())
+			window := checker.MinerConfirmationWindow()
 			activationHeight := window - (node.height % window)
 			log.Warnf("Unknown new rules are about to activate in "+
 				"%d blocks (bit %d)", activationHeight, bit)
diff --git a/btcjson/dagsvrcmds.go b/btcjson/dagsvrcmds.go
index ac8994813..69a9b1f43 100644
--- a/btcjson/dagsvrcmds.go
+++ b/btcjson/dagsvrcmds.go
@@ -719,8 +719,8 @@ func NewValidateAddressCmd(address string) *ValidateAddressCmd {
 
 // VerifyDAGCmd defines the verifyDag JSON-RPC command.
 type VerifyDAGCmd struct {
-	CheckLevel *int32 `jsonrpcdefault:"3"`
-	CheckDepth *int32 `jsonrpcdefault:"288"` // 0 = all
+	CheckLevel *uint64 `jsonrpcdefault:"3"`
+	CheckDepth *uint64 `jsonrpcdefault:"288"` // 0 = all
 }
 
 // NewVerifyDAGCmd returns a new instance which can be used to issue a
@@ -728,7 +728,7 @@ type VerifyDAGCmd struct {
 //
 // The parameters which are pointers indicate they are optional.  Passing nil
 // for optional parameters will use the default value.
-func NewVerifyDAGCmd(checkLevel, checkDepth *int32) *VerifyDAGCmd {
+func NewVerifyDAGCmd(checkLevel, checkDepth *uint64) *VerifyDAGCmd {
 	return &VerifyDAGCmd{
 		CheckLevel: checkLevel,
 		CheckDepth: checkDepth,
diff --git a/btcjson/dagsvrcmds_test.go b/btcjson/dagsvrcmds_test.go
index e68bcd311..7c60b68a8 100644
--- a/btcjson/dagsvrcmds_test.go
+++ b/btcjson/dagsvrcmds_test.go
@@ -1027,8 +1027,8 @@ func TestDAGSvrCmds(t *testing.T) {
 			},
 			marshalled: `{"jsonrpc":"1.0","method":"verifyDag","params":[],"id":1}`,
 			unmarshalled: &btcjson.VerifyDAGCmd{
-				CheckLevel: btcjson.Int32(3),
-				CheckDepth: btcjson.Int32(288),
+				CheckLevel: btcjson.Uint64(3),
+				CheckDepth: btcjson.Uint64(288),
 			},
 		},
 		{
@@ -1037,12 +1037,12 @@ func TestDAGSvrCmds(t *testing.T) {
 				return btcjson.NewCmd("verifyDag", 2)
 			},
 			staticCmd: func() interface{} {
-				return btcjson.NewVerifyDAGCmd(btcjson.Int32(2), nil)
+				return btcjson.NewVerifyDAGCmd(btcjson.Uint64(2), nil)
 			},
 			marshalled: `{"jsonrpc":"1.0","method":"verifyDag","params":[2],"id":1}`,
 			unmarshalled: &btcjson.VerifyDAGCmd{
-				CheckLevel: btcjson.Int32(2),
-				CheckDepth: btcjson.Int32(288),
+				CheckLevel: btcjson.Uint64(2),
+				CheckDepth: btcjson.Uint64(288),
 			},
 		},
 		{
@@ -1051,12 +1051,12 @@ func TestDAGSvrCmds(t *testing.T) {
 				return btcjson.NewCmd("verifyDag", 2, 500)
 			},
 			staticCmd: func() interface{} {
-				return btcjson.NewVerifyDAGCmd(btcjson.Int32(2), btcjson.Int32(500))
+				return btcjson.NewVerifyDAGCmd(btcjson.Uint64(2), btcjson.Uint64(500))
 			},
 			marshalled: `{"jsonrpc":"1.0","method":"verifyDag","params":[2,500],"id":1}`,
 			unmarshalled: &btcjson.VerifyDAGCmd{
-				CheckLevel: btcjson.Int32(2),
-				CheckDepth: btcjson.Int32(500),
+				CheckLevel: btcjson.Uint64(2),
+				CheckDepth: btcjson.Uint64(500),
 			},
 		},
 		{
diff --git a/btcjson/dagsvrresults.go b/btcjson/dagsvrresults.go
index 5f0f2dad9..817b4ec6f 100644
--- a/btcjson/dagsvrresults.go
+++ b/btcjson/dagsvrresults.go
@@ -12,7 +12,7 @@ import "encoding/json"
 type GetBlockHeaderVerboseResult struct {
 	Hash          string   `json:"hash"`
 	Confirmations uint64   `json:"confirmations"`
-	Height        int32    `json:"height"`
+	Height        uint64   `json:"height"`
 	Version       int32    `json:"version"`
 	VersionHex    string   `json:"versionHex"`
 	MerkleRoot    string   `json:"merkleRoot"`
@@ -31,7 +31,7 @@ type GetBlockVerboseResult struct {
 	Hash          string        `json:"hash"`
 	Confirmations uint64        `json:"confirmations"`
 	Size          int32         `json:"size"`
-	Height        int64         `json:"height"`
+	Height        uint64        `json:"height"`
 	Version       int32         `json:"version"`
 	VersionHex    string        `json:"versionHex"`
 	MerkleRoot    string        `json:"merkleRoot"`
@@ -99,14 +99,14 @@ type Bip9SoftForkDescription struct {
 // command.
 type GetBlockDAGInfoResult struct {
 	DAG                  string                              `json:"dag"`
-	Blocks               int32                               `json:"blocks"`
-	Headers              int32                               `json:"headers"`
+	Blocks               uint64                              `json:"blocks"`
+	Headers              uint64                              `json:"headers"`
 	TipHashes            []string                            `json:"tipHashes"`
 	Difficulty           float64                             `json:"difficulty"`
 	MedianTime           int64                               `json:"medianTime"`
 	VerificationProgress float64                             `json:"verificationProgress,omitempty"`
 	Pruned               bool                                `json:"pruned"`
-	PruneHeight          int32                               `json:"pruneHeight,omitempty"`
+	PruneHeight          uint64                              `json:"pruneHeight,omitempty"`
 	DAGWork              string                              `json:"dagWork,omitempty"`
 	SoftForks            []*SoftForkDescription              `json:"softForks"`
 	Bip9SoftForks        map[string]*Bip9SoftForkDescription `json:"bip9SoftForks"`
@@ -135,7 +135,7 @@ type GetBlockTemplateResult struct {
 	// CoinbaseTxn or CoinbaseValue must be specified, but not both.
 	Bits          string                     `json:"bits"`
 	CurTime       int64                      `json:"curTime"`
-	Height        int64                      `json:"height"`
+	Height        uint64                     `json:"height"`
 	ParentHashes  []string                   `json:"parentHashes"`
 	SigOpLimit    int64                      `json:"sigOpLimit,omitempty"`
 	SizeLimit     int64                      `json:"sizeLimit,omitempty"`
@@ -173,7 +173,7 @@ type GetMempoolEntryResult struct {
 	Fee              float64  `json:"fee"`
 	ModifiedFee      float64  `json:"modifiedFee"`
 	Time             int64    `json:"time"`
-	Height           int64    `json:"height"`
+	Height           uint64   `json:"height"`
 	StartingPriority float64  `json:"startingPriority"`
 	CurrentPriority  float64  `json:"currentPriority"`
 	DescendantCount  int64    `json:"descendantCount"`
@@ -257,7 +257,7 @@ type GetRawMempoolVerboseResult struct {
 	Size             int32    `json:"size"`
 	Fee              float64  `json:"fee"`
 	Time             int64    `json:"time"`
-	Height           int64    `json:"height"`
+	Height           uint64   `json:"height"`
 	StartingPriority float64  `json:"startingPriority"`
 	CurrentPriority  float64  `json:"currentPriority"`
 	Depends          []string `json:"depends"`
@@ -426,7 +426,7 @@ type GetWorkResult struct {
 type InfoDAGResult struct {
 	Version         int32   `json:"version"`
 	ProtocolVersion int32   `json:"protocolVersion"`
-	Blocks          int32   `json:"blocks"`
+	Blocks          uint64  `json:"blocks"`
 	TimeOffset      int64   `json:"timeOffset"`
 	Connections     int32   `json:"connections"`
 	Proxy           string  `json:"proxy"`
diff --git a/btcjson/dagsvrwsntfns.go b/btcjson/dagsvrwsntfns.go
index cbf8132a2..b963dded8 100644
--- a/btcjson/dagsvrwsntfns.go
+++ b/btcjson/dagsvrwsntfns.go
@@ -62,14 +62,14 @@ const (
 // FilteredBlockAddedNtfn defines the filteredBlockAdded JSON-RPC
 // notification.
 type FilteredBlockAddedNtfn struct {
-	Height        int32
+	Height        uint64
 	Header        string
 	SubscribedTxs []string
 }
 
 // NewFilteredBlockAddedNtfn returns a new instance which can be used to
 // issue a filteredBlockAdded JSON-RPC notification.
-func NewFilteredBlockAddedNtfn(height int32, header string, subscribedTxs []string) *FilteredBlockAddedNtfn {
+func NewFilteredBlockAddedNtfn(height uint64, header string, subscribedTxs []string) *FilteredBlockAddedNtfn {
 	return &FilteredBlockAddedNtfn{
 		Height:        height,
 		Header:        header,
@@ -79,7 +79,7 @@ func NewFilteredBlockAddedNtfn(height int32, header string, subscribedTxs []stri
 
 // BlockDetails describes details of a tx in a block.
 type BlockDetails struct {
-	Height int32  `json:"height"`
+	Height uint64 `json:"height"`
 	Hash   string `json:"hash"`
 	Index  int    `json:"index"`
 	Time   int64  `json:"time"`
@@ -132,7 +132,7 @@ func NewRedeemingTxNtfn(hexTx string, block *BlockDetails) *RedeemingTxNtfn {
 // NOTE: Deprecated. Not used with rescanblocks command.
 type RescanFinishedNtfn struct {
 	Hash   string
-	Height int32
+	Height uint64
 	Time   int64
 }
 
@@ -140,7 +140,7 @@ type RescanFinishedNtfn struct {
 // rescanFinished JSON-RPC notification.
 //
 // NOTE: Deprecated. Not used with rescanblocks command.
-func NewRescanFinishedNtfn(hash string, height int32, time int64) *RescanFinishedNtfn {
+func NewRescanFinishedNtfn(hash string, height uint64, time int64) *RescanFinishedNtfn {
 	return &RescanFinishedNtfn{
 		Hash:   hash,
 		Height: height,
@@ -153,7 +153,7 @@ func NewRescanFinishedNtfn(hash string, height int32, time int64) *RescanFinishe
 // NOTE: Deprecated. Not used with rescanblocks command.
 type RescanProgressNtfn struct {
 	Hash   string
-	Height int32
+	Height uint64
 	Time   int64
 }
 
@@ -161,7 +161,7 @@ type RescanProgressNtfn struct {
 // rescanProgress JSON-RPC notification.
 //
 // NOTE: Deprecated. Not used with rescanblocks command.
-func NewRescanProgressNtfn(hash string, height int32, time int64) *RescanProgressNtfn {
+func NewRescanProgressNtfn(hash string, height uint64, time int64) *RescanProgressNtfn {
 	return &RescanProgressNtfn{
 		Hash:   hash,
 		Height: height,
diff --git a/btcjson/walletsvrresults.go b/btcjson/walletsvrresults.go
index 578b2820d..4a9ab4d4e 100644
--- a/btcjson/walletsvrresults.go
+++ b/btcjson/walletsvrresults.go
@@ -157,5 +157,5 @@ type ValidateAddressWalletResult struct {
 // GetBestBlockResult models the data from the getbestblock command.
 type GetBestBlockResult struct {
 	Hash   string `json:"hash"`
-	Height int32  `json:"height"`
+	Height uint64 `json:"height"`
 }
diff --git a/cmd/findcheckpoint/findcheckpoint.go b/cmd/findcheckpoint/findcheckpoint.go
index 013571244..a4f9304e4 100644
--- a/cmd/findcheckpoint/findcheckpoint.go
+++ b/cmd/findcheckpoint/findcheckpoint.go
@@ -58,7 +58,7 @@ func findCandidates(dag *blockdag.BlockDAG, highestTipHash *daghash.Hash) ([]*da
 
 	// The latest known block must be at least the last known checkpoint
 	// plus required checkpoint confirmations.
-	checkpointConfirmations := int32(blockdag.CheckpointConfirmations)
+	checkpointConfirmations := uint64(blockdag.CheckpointConfirmations)
 	requiredHeight := latestCheckpoint.Height + checkpointConfirmations
 	if block.Height() < requiredHeight {
 		return nil, fmt.Errorf("the block database is only at height "+
@@ -83,7 +83,7 @@ func findCandidates(dag *blockdag.BlockDAG, highestTipHash *daghash.Hash) ([]*da
 
 	// Loop backwards through the DAG to find checkpoint candidates.
 	candidates := make([]*dagconfig.Checkpoint, 0, cfg.NumCandidates)
-	numTested := int32(0)
+	numTested := uint64(0)
 	for len(candidates) < cfg.NumCandidates && block.Height() > requiredHeight {
 		// Display progress.
 		if numTested%progressInterval == 0 {
diff --git a/config/config.go b/config/config.go
index e0a001150..647f5e28f 100644
--- a/config/config.go
+++ b/config/config.go
@@ -226,7 +226,7 @@ func newCheckpointFromStr(checkpoint string) (dagconfig.Checkpoint, error) {
 			checkpoint)
 	}
 
-	height, err := strconv.ParseInt(parts[0], 10, 32)
+	height, err := strconv.ParseInt(parts[0], 10, 64)
 	if err != nil {
 		return dagconfig.Checkpoint{}, fmt.Errorf("unable to parse "+
 			"checkpoint %q due to malformed height", checkpoint)
@@ -243,7 +243,7 @@ func newCheckpointFromStr(checkpoint string) (dagconfig.Checkpoint, error) {
 	}
 
 	return dagconfig.Checkpoint{
-		Height: int32(height),
+		Height: uint64(height),
 		Hash:   hash,
 	}, nil
 }
diff --git a/dagconfig/params.go b/dagconfig/params.go
index 69255d80e..edbcbfba4 100644
--- a/dagconfig/params.go
+++ b/dagconfig/params.go
@@ -57,7 +57,7 @@ const phantomK = 10
 // documentation for blockchain.IsCheckpointCandidate for details on the
 // selection criteria.
 type Checkpoint struct {
-	Height int32
+	Height uint64
 	Hash   *daghash.Hash
 }
 
@@ -130,11 +130,11 @@ type Params struct {
 
 	// BlockRewardMaturity is the number of blocks required before newly mined
 	// coins (coinbase or fee transactions) can be spent.
-	BlockRewardMaturity uint16
+	BlockRewardMaturity uint64
 
 	// SubsidyReductionInterval is the interval of blocks before the subsidy
 	// is reduced.
-	SubsidyReductionInterval int32
+	SubsidyReductionInterval uint64
 
 	// TargetTimespan is the desired amount of time that should elapse
 	// before the block difficulty requirement is examined to determine how
@@ -182,8 +182,8 @@ type Params struct {
 	//
 	// Deployments define the specific consensus rule changes to be voted
 	// on.
-	RuleChangeActivationThreshold uint32
-	MinerConfirmationWindow       uint32
+	RuleChangeActivationThreshold uint64
+	MinerConfirmationWindow       uint64
 	Deployments                   [DefinedDeployments]ConsensusDeployment
 
 	// Mempool parameters
diff --git a/integration/bip0009_test.go b/integration/bip0009_test.go
index ecf062d92..3a0b82909 100644
--- a/integration/bip0009_test.go
+++ b/integration/bip0009_test.go
@@ -52,12 +52,12 @@ func assertVersionBit(r *rpctest.Harness, t *testing.T, hash *daghash.Hash, bit
 
 // assertChainHeight retrieves the current chain height from the given test
 // harness and ensures it matches the provided expected height.
-func assertChainHeight(r *rpctest.Harness, t *testing.T, expectedHeight uint32) {
+func assertChainHeight(r *rpctest.Harness, t *testing.T, expectedHeight uint64) {
 	height, err := r.Node.GetBlockCount()
 	if err != nil {
 		t.Fatalf("failed to retrieve block height: %v", err)
 	}
-	if uint32(height) != expectedHeight {
+	if height != expectedHeight {
 		_, _, line, _ := runtime.Caller(1)
 		t.Fatalf("assertion failed at line %d: block height of %d "+
 			"is not the expected %d", line, height, expectedHeight)
diff --git a/integration/rpctest/blockgen.go b/integration/rpctest/blockgen.go
index 506fdfd59..eba2e93fd 100644
--- a/integration/rpctest/blockgen.go
+++ b/integration/rpctest/blockgen.go
@@ -88,14 +88,14 @@ func solveBlock(header *wire.BlockHeader, targetDifficulty *big.Int) bool {
 // standardCoinbaseScript returns a standard script suitable for use as the
 // signature script of the coinbase transaction of a new block. In particular,
 // it starts with the block height that is required by version 2 blocks.
-func standardCoinbaseScript(nextBlockHeight int32, extraNonce uint64) ([]byte, error) {
+func standardCoinbaseScript(nextBlockHeight uint64, extraNonce uint64) ([]byte, error) {
 	return txscript.NewScriptBuilder().AddInt64(int64(nextBlockHeight)).
 		AddInt64(int64(extraNonce)).Script()
 }
 
 // createCoinbaseTx returns a coinbase transaction paying an appropriate
 // subsidy based on the passed block height to the provided address.
-func createCoinbaseTx(coinbaseScript []byte, nextBlockHeight int32,
+func createCoinbaseTx(coinbaseScript []byte, nextBlockHeight uint64,
 	addr util.Address, mineTo []wire.TxOut,
 	net *dagconfig.Params) (*util.Tx, error) {
 
@@ -139,7 +139,7 @@ func CreateBlock(parentBlock *util.Block, inclusionTxs []*util.Tx,
 
 	var (
 		parentHash      *daghash.Hash
-		blockHeight     int32
+		blockHeight     uint64
 		parentBlockTime time.Time
 	)
 
diff --git a/integration/rpctest/memwallet.go b/integration/rpctest/memwallet.go
index 1c5fe4407..4b7e2f12b 100644
--- a/integration/rpctest/memwallet.go
+++ b/integration/rpctest/memwallet.go
@@ -39,20 +39,20 @@ type utxo struct {
 	pkScript       []byte
 	value          util.Amount
 	keyIndex       uint32
-	maturityHeight int32
+	maturityHeight uint64
 	isLocked       bool
 }
 
 // isMature returns true if the target utxo is considered "mature" at the
 // passed block height. Otherwise, false is returned.
-func (u *utxo) isMature(height int32) bool {
+func (u *utxo) isMature(height uint64) bool {
 	return height >= u.maturityHeight
 }
 
 // dagUpdate encapsulates an update to the current DAG. This struct is
 // used to sync up the memWallet each time a new block is connected to the DAG.
 type dagUpdate struct {
-	blockHeight  int32
+	blockHeight  uint64
 	filteredTxns []*util.Tx
 	isConnect    bool // True if connect, false if disconnect
 }
@@ -80,7 +80,7 @@ type memWallet struct {
 
 	// currentHeight is the latest height the wallet is known to be synced
 	// to.
-	currentHeight int32
+	currentHeight uint64
 
 	// addrs tracks all addresses belonging to the wallet. The addresses
 	// are indexed by their keypath from the hdRoot.
@@ -93,7 +93,7 @@ type memWallet struct {
 	// received. Once a block is disconnected, the undo entry for the
 	// particular height is evaluated, thereby rewinding the effect of the
 	// disconnected block on the wallet's set of spendable utxos.
-	reorgJournal map[int32]*undoEntry
+	reorgJournal map[uint64]*undoEntry
 
 	dagUpdates      []*dagUpdate
 	dagUpdateSignal chan struct{}
@@ -150,7 +150,7 @@ func newMemWallet(net *dagconfig.Params, harnessID uint32) (*memWallet, error) {
 		addrs:           addrs,
 		utxos:           make(map[wire.OutPoint]*utxo),
 		dagUpdateSignal: make(chan struct{}),
-		reorgJournal:    make(map[int32]*undoEntry),
+		reorgJournal:    make(map[uint64]*undoEntry),
 	}, nil
 }
 
@@ -162,7 +162,7 @@ func (m *memWallet) Start() {
 // SyncedHeight returns the height the wallet is known to be synced to.
 //
 // This function is safe for concurrent access.
-func (m *memWallet) SyncedHeight() int32 {
+func (m *memWallet) SyncedHeight() uint64 {
 	m.RLock()
 	defer m.RUnlock()
 	return m.currentHeight
@@ -177,7 +177,7 @@ func (m *memWallet) SetRPCClient(rpcClient *rpcclient.Client) {
 // IngestBlock is a call-back which is to be triggered each time a new block is
 // connected to the blockDAG. It queues the update for the DAG syncer,
 // calling the private version in sequential order.
-func (m *memWallet) IngestBlock(height int32, header *wire.BlockHeader, filteredTxns []*util.Tx) {
+func (m *memWallet) IngestBlock(height uint64, header *wire.BlockHeader, filteredTxns []*util.Tx) {
 	// Append this new DAG update to the end of the queue of new DAG
 	// updates.
 	m.dagMtx.Lock()
@@ -260,9 +260,9 @@ func (m *memWallet) evalOutputs(outputs []*wire.TxOut, txID *daghash.TxID,
 			// If this is a coinbase output, then we mark the
 			// maturity height at the proper block height in the
 			// future.
-			var maturityHeight int32
+			var maturityHeight uint64
 			if isCoinbase {
-				maturityHeight = m.currentHeight + int32(m.net.BlockRewardMaturity)
+				maturityHeight = m.currentHeight + m.net.BlockRewardMaturity
 			}
 
 			op := wire.OutPoint{TxID: *txID, Index: uint32(i)}
diff --git a/integration/rpctest/rpc_harness.go b/integration/rpctest/rpc_harness.go
index 0252af2d5..e3bc20fdc 100644
--- a/integration/rpctest/rpc_harness.go
+++ b/integration/rpctest/rpc_harness.go
@@ -171,7 +171,7 @@ func New(activeNet *dagconfig.Params, handlers *rpcclient.NotificationHandlers,
 	// callback.
 	if handlers.OnFilteredBlockAdded != nil {
 		obc := handlers.OnFilteredBlockAdded
-		handlers.OnFilteredBlockAdded = func(height int32, header *wire.BlockHeader, filteredTxns []*util.Tx) {
+		handlers.OnFilteredBlockAdded = func(height uint64, header *wire.BlockHeader, filteredTxns []*util.Tx) {
 			wallet.IngestBlock(height, header, filteredTxns)
 			obc(height, header, filteredTxns)
 		}
diff --git a/integration/rpctest/utils.go b/integration/rpctest/utils.go
index 2430c6fa5..1d776841b 100644
--- a/integration/rpctest/utils.go
+++ b/integration/rpctest/utils.go
@@ -81,7 +81,7 @@ func syncBlocks(nodes []*Harness) error {
 retry:
 	for !blocksMatch {
 		var parentHash *daghash.Hash
-		var prevHeight int32
+		var prevHeight uint64
 		for _, node := range nodes {
 			blockHash, blockHeight, err := node.Node.GetBestBlock()
 			if err != nil {
diff --git a/mempool/estimatefee.go b/mempool/estimatefee.go
index fede4d6ef..a6b822766 100644
--- a/mempool/estimatefee.go
+++ b/mempool/estimatefee.go
@@ -100,11 +100,11 @@ type observedTransaction struct {
 	feeRate SatoshiPerByte
 
 	// The block height when it was observed.
-	observed int32
+	observed uint64
 
 	// The height of the block in which it was mined.
 	// If the transaction has not yet been mined, it is zero.
-	mined int32
+	mined uint64
 }
 
 func (o *observedTransaction) Serialize(w io.Writer) {
@@ -163,7 +163,7 @@ type FeeEstimator struct {
 	minRegisteredBlocks uint32
 
 	// The last known height.
-	lastKnownHeight int32
+	lastKnownHeight uint64
 
 	// The number of blocks that have been registered.
 	numBlocksRegistered uint32
@@ -327,7 +327,7 @@ func (ef *FeeEstimator) RegisterBlock(block *util.Block) error {
 }
 
 // LastKnownHeight returns the height of the last block which was registered.
-func (ef *FeeEstimator) LastKnownHeight() int32 {
+func (ef *FeeEstimator) LastKnownHeight() uint64 {
 	ef.mtx.Lock()
 	defer ef.mtx.Unlock()
 
diff --git a/mempool/estimatefee_test.go b/mempool/estimatefee_test.go
index 8ce61fc5e..4e556f19b 100644
--- a/mempool/estimatefee_test.go
+++ b/mempool/estimatefee_test.go
@@ -42,7 +42,7 @@ type estimateFeeTester struct {
 	ef      *FeeEstimator
 	t       *testing.T
 	version int32
-	height  int32
+	height  uint64
 	last    *lastBlock
 }
 
diff --git a/mempool/mempool.go b/mempool/mempool.go
index ca44dff8b..44f95125e 100644
--- a/mempool/mempool.go
+++ b/mempool/mempool.go
@@ -66,7 +66,7 @@ type Config struct {
 
 	// BestHeight defines the function to use to access the block height of
 	// the current best chain.
-	BestHeight func() int32
+	BestHeight func() uint64
 
 	// MedianTimePast defines the function to use in order to access the
 	// median time past calculated from the point-of-view of the current
@@ -606,7 +606,10 @@ func (mp *TxPool) RemoveDoubleSpends(tx *util.Tx) {
 // helper for maybeAcceptTransaction.
 //
 // This function MUST be called with the mempool lock held (for writes).
-func (mp *TxPool) addTransaction(tx *util.Tx, height int32, fee uint64, parentsInPool []*wire.OutPoint) *TxDesc {
+func (mp *TxPool) addTransaction(tx *util.Tx, height uint64, fee uint64, parentsInPool []*wire.OutPoint) *TxDesc {
+	mp.cfg.DAG.RLock()
+	defer mp.cfg.DAG.RUnlock()
+
 	// Add the transaction to the pool and mark the referenced outpoints
 	// as spent by the pool.
 	txD := &TxDesc{
@@ -1284,7 +1287,7 @@ func (mp *TxPool) RawMempoolVerbose() map[string]*btcjson.GetRawMempoolVerboseRe
 			Size:             int32(tx.MsgTx().SerializeSize()),
 			Fee:              util.Amount(desc.Fee).ToBTC(),
 			Time:             desc.Added.Unix(),
-			Height:           int64(desc.Height),
+			Height:           desc.Height,
 			StartingPriority: desc.StartingPriority,
 			CurrentPriority:  currentPriority,
 			Depends:          make([]string, 0),
diff --git a/mempool/mempool_test.go b/mempool/mempool_test.go
index db647cb1b..b92871b9a 100644
--- a/mempool/mempool_test.go
+++ b/mempool/mempool_test.go
@@ -35,13 +35,13 @@ import (
 // transactions to appear as though they are spending completely valid utxos.
 type fakeChain struct {
 	sync.RWMutex
-	currentHeight  int32
+	currentHeight  uint64
 	medianTimePast time.Time
 }
 
 // BestHeight returns the current height associated with the fake chain
 // instance.
-func (s *fakeChain) BestHeight() int32 {
+func (s *fakeChain) BestHeight() uint64 {
 	s.RLock()
 	height := s.currentHeight
 	s.RUnlock()
@@ -49,7 +49,7 @@ func (s *fakeChain) BestHeight() int32 {
 }
 
 // SetHeight sets the current height associated with the fake chain instance.
-func (s *fakeChain) SetHeight(height int32) {
+func (s *fakeChain) SetHeight(height uint64) {
 	s.Lock()
 	s.currentHeight = height
 	s.Unlock()
@@ -121,7 +121,7 @@ type poolHarness struct {
 // address associated with the harness.  It automatically uses a standard
 // signature script that starts with the block height that is required by
 // version 2 blocks.
-func (p *poolHarness) CreateCoinbaseTx(blockHeight int32, numOutputs uint32) (*util.Tx, error) {
+func (p *poolHarness) CreateCoinbaseTx(blockHeight uint64, numOutputs uint32) (*util.Tx, error) {
 	// Create standard coinbase script.
 	extraNonce := int64(0)
 	coinbaseScript, err := txscript.NewScriptBuilder().
@@ -344,7 +344,7 @@ func newPoolHarness(dagParams *dagconfig.Params, numOutputs uint32, dbName strin
 		outpoints = append(outpoints, txOutToSpendableOutpoint(coinbase, i))
 	}
 	if dagParams.BlockRewardMaturity != 0 {
-		harness.chain.SetHeight(int32(dagParams.BlockRewardMaturity) + curHeight)
+		harness.chain.SetHeight(dagParams.BlockRewardMaturity + curHeight)
 	} else {
 		harness.chain.SetHeight(curHeight + 1)
 	}
diff --git a/mempool/policy.go b/mempool/policy.go
index ba8d8ed9f..5d95ab729 100644
--- a/mempool/policy.go
+++ b/mempool/policy.go
@@ -245,7 +245,7 @@ func isDust(txOut *wire.TxOut, minRelayTxFee util.Amount) bool {
 // finalized, conforming to more stringent size constraints, having scripts
 // of recognized forms, and not containing "dust" outputs (those that are
 // so small it costs more to process them than they are worth).
-func checkTransactionStandard(tx *util.Tx, height int32,
+func checkTransactionStandard(tx *util.Tx, height uint64,
 	medianTimePast time.Time, policy *Policy) error {
 
 	// The transaction must be a currently supported version.
diff --git a/mempool/policy_test.go b/mempool/policy_test.go
index af05826d7..766be6a94 100644
--- a/mempool/policy_test.go
+++ b/mempool/policy_test.go
@@ -307,7 +307,7 @@ func TestCheckTransactionStandard(t *testing.T) {
 	tests := []struct {
 		name       string
 		tx         *wire.MsgTx
-		height     int32
+		height     uint64
 		isStandard bool
 		code       wire.RejectCode
 	}{
diff --git a/mining/cpuminer/cpuminer.go b/mining/cpuminer/cpuminer.go
index 892603055..4d97d8775 100644
--- a/mining/cpuminer/cpuminer.go
+++ b/mining/cpuminer/cpuminer.go
@@ -206,7 +206,7 @@ func (m *CPUMiner) submitBlock(block *util.Block) bool {
 // This function will return early with false when conditions that trigger a
 // stale block such as a new block showing up or periodically when there are
 // new transactions and enough time has elapsed without finding a solution.
-func (m *CPUMiner) solveBlock(msgBlock *wire.MsgBlock, blockHeight int32,
+func (m *CPUMiner) solveBlock(msgBlock *wire.MsgBlock, blockHeight uint64,
 	ticker *time.Ticker, quit chan struct{}) bool {
 
 	// Create some convenience variables.
diff --git a/mining/mining.go b/mining/mining.go
index a4244d1d8..3bd3bb420 100644
--- a/mining/mining.go
+++ b/mining/mining.go
@@ -46,7 +46,7 @@ type TxDesc struct {
 
 	// Height is the block height when the entry was added to the the source
 	// pool.
-	Height int32
+	Height uint64
 
 	// Fee is the total fee the transaction associated with the entry pays.
 	Fee uint64
@@ -198,9 +198,8 @@ type BlockTemplate struct {
 	// transaction in the generated template performs.
 	SigOpCounts []int64
 
-	// Height is the height at which the block template connects to the main
-	// chain.
-	Height int32
+	// Height is the height at which the block template connects to the DAG
+	Height uint64
 
 	// ValidPayAddress indicates whether or not the template coinbase pays
 	// to an address or is redeemable by anyone.  See the documentation on
@@ -213,7 +212,7 @@ type BlockTemplate struct {
 // signature script of the coinbase transaction of a new block.  In particular,
 // it starts with the block height that is required by version 2 blocks and adds
 // the extra nonce as well as additional coinbase flags.
-func StandardCoinbaseScript(nextBlockHeight int32, extraNonce uint64) ([]byte, error) {
+func StandardCoinbaseScript(nextBlockHeight uint64, extraNonce uint64) ([]byte, error) {
 	return txscript.NewScriptBuilder().AddInt64(int64(nextBlockHeight)).
 		AddInt64(int64(extraNonce)).AddData([]byte(CoinbaseFlags)).
 		Script()
@@ -225,7 +224,7 @@ func StandardCoinbaseScript(nextBlockHeight int32, extraNonce uint64) ([]byte, e
 //
 // See the comment for NewBlockTemplate for more information about why the nil
 // address handling is useful.
-func CreateCoinbaseTx(params *dagconfig.Params, coinbaseScript []byte, nextBlockHeight int32, addr util.Address) (*util.Tx, error) {
+func CreateCoinbaseTx(params *dagconfig.Params, coinbaseScript []byte, nextBlockHeight uint64, addr util.Address) (*util.Tx, error) {
 	// Create the script to pay to the provided payment address if one was
 	// specified.  Otherwise create a script that allows the coinbase to be
 	// redeemable by anyone.
@@ -721,7 +720,7 @@ func (g *BlkTmplGenerator) UpdateBlockTime(msgBlock *wire.MsgBlock) error {
 // block by regenerating the coinbase script with the passed value and block
 // height.  It also recalculates and updates the new merkle root that results
 // from changing the coinbase script.
-func (g *BlkTmplGenerator) UpdateExtraNonce(msgBlock *wire.MsgBlock, blockHeight int32, extraNonce uint64) error {
+func (g *BlkTmplGenerator) UpdateExtraNonce(msgBlock *wire.MsgBlock, blockHeight uint64, extraNonce uint64) error {
 	coinbaseScript, err := StandardCoinbaseScript(blockHeight, extraNonce)
 	if err != nil {
 		return err
@@ -749,7 +748,7 @@ func (g *BlkTmplGenerator) UpdateExtraNonce(msgBlock *wire.MsgBlock, blockHeight
 }
 
 // DAGHeight returns the DAG's height
-func (g *BlkTmplGenerator) DAGHeight() int32 {
+func (g *BlkTmplGenerator) DAGHeight() uint64 {
 	return g.dag.Height()
 }
 
diff --git a/mining/mining_test.go b/mining/mining_test.go
index 4f02fcf44..4af584148 100644
--- a/mining/mining_test.go
+++ b/mining/mining_test.go
@@ -148,7 +148,7 @@ func TestNewBlockTemplate(t *testing.T) {
 	}
 
 	var createCoinbaseTxPatch *monkey.PatchGuard
-	createCoinbaseTxPatch = monkey.Patch(CreateCoinbaseTx, func(params *dagconfig.Params, coinbaseScript []byte, nextBlockHeight int32, addr util.Address) (*util.Tx, error) {
+	createCoinbaseTxPatch = monkey.Patch(CreateCoinbaseTx, func(params *dagconfig.Params, coinbaseScript []byte, nextBlockHeight uint64, addr util.Address) (*util.Tx, error) {
 		createCoinbaseTxPatch.Unpatch()
 		defer createCoinbaseTxPatch.Restore()
 		tx, err := CreateCoinbaseTx(params, coinbaseScript, nextBlockHeight, addr)
@@ -298,7 +298,7 @@ func TestNewBlockTemplate(t *testing.T) {
 	standardCoinbaseScriptErrString := "standardCoinbaseScript err"
 
 	var standardCoinbaseScriptPatch *monkey.PatchGuard
-	standardCoinbaseScriptPatch = monkey.Patch(StandardCoinbaseScript, func(nextBlockHeight int32, extraNonce uint64) ([]byte, error) {
+	standardCoinbaseScriptPatch = monkey.Patch(StandardCoinbaseScript, func(nextBlockHeight uint64, extraNonce uint64) ([]byte, error) {
 		return nil, errors.New(standardCoinbaseScriptErrString)
 	})
 	defer standardCoinbaseScriptPatch.Unpatch()
diff --git a/mining/policy.go b/mining/policy.go
index d0b8944e7..87d7535b0 100644
--- a/mining/policy.go
+++ b/mining/policy.go
@@ -54,7 +54,7 @@ func minInt(a, b int) int {
 // age is the sum of this value for each txin.  Any inputs to the transaction
 // which are currently in the mempool and hence not mined into a block yet,
 // contribute no additional input age to the transaction.
-func calcInputValueAge(tx *wire.MsgTx, utxoSet blockdag.UTXOSet, nextBlockHeight int32) float64 {
+func calcInputValueAge(tx *wire.MsgTx, utxoSet blockdag.UTXOSet, nextBlockHeight uint64) float64 {
 	var totalInputAge float64
 	for _, txIn := range tx.TxIn {
 		// Don't attempt to accumulate the total input age if the
@@ -65,7 +65,7 @@ func calcInputValueAge(tx *wire.MsgTx, utxoSet blockdag.UTXOSet, nextBlockHeight
 			// have their block height set to a special constant.
 			// Their input age should computed as zero since their
 			// parent hasn't made it into a block yet.
-			var inputAge int32
+			var inputAge uint64
 			originHeight := entry.BlockHeight()
 			if originHeight == UnminedHeight {
 				inputAge = 0
@@ -86,7 +86,7 @@ func calcInputValueAge(tx *wire.MsgTx, utxoSet blockdag.UTXOSet, nextBlockHeight
 // of each of its input values multiplied by their age (# of confirmations).
 // Thus, the final formula for the priority is:
 // sum(inputValue * inputAge) / adjustedTxSize
-func CalcPriority(tx *wire.MsgTx, utxoSet blockdag.UTXOSet, nextBlockHeight int32) float64 {
+func CalcPriority(tx *wire.MsgTx, utxoSet blockdag.UTXOSet, nextBlockHeight uint64) float64 {
 	// In order to encourage spending multiple old unspent transaction
 	// outputs thereby reducing the total set, don't count the constant
 	// overhead for each input as well as enough bytes of the signature
diff --git a/mining/policy_test.go b/mining/policy_test.go
index dd62a54b6..a2b1b4cc7 100644
--- a/mining/policy_test.go
+++ b/mining/policy_test.go
@@ -46,7 +46,7 @@ func hexToBytes(s string) []byte {
 // provided source transactions as if there were available at the respective
 // block height specified in the heights slice.  The length of the source txns
 // and source tx heights must match or it will panic.
-func newUTXOSet(sourceTxns []*wire.MsgTx, sourceTxHeights []int32) blockdag.UTXOSet {
+func newUTXOSet(sourceTxns []*wire.MsgTx, sourceTxHeights []uint64) blockdag.UTXOSet {
 	if len(sourceTxns) != len(sourceTxHeights) {
 		panic("each transaction must have its block height specified")
 	}
@@ -130,14 +130,14 @@ func TestCalcPriority(t *testing.T) {
 		name       string           // test description
 		tx         *wire.MsgTx      // tx to calc priority for
 		utxoSet    blockdag.UTXOSet // inputs to tx
-		nextHeight int32            // height for priority calc
+		nextHeight uint64           // height for priority calc
 		want       float64          // expected priority
 	}{
 		{
 			name: "one height 7 input, prio tx height 169",
 			tx:   commonRedeemTx1,
 			utxoSet: newUTXOSet([]*wire.MsgTx{commonSourceTx1},
-				[]int32{7}),
+				[]uint64{7}),
 			nextHeight: 169,
 			want:       1.125e+10,
 		},
@@ -145,7 +145,7 @@ func TestCalcPriority(t *testing.T) {
 			name: "one height 100 input, prio tx height 169",
 			tx:   commonRedeemTx1,
 			utxoSet: newUTXOSet([]*wire.MsgTx{commonSourceTx1},
-				[]int32{100}),
+				[]uint64{100}),
 			nextHeight: 169,
 			want:       4.791666666666667e+09,
 		},
@@ -153,7 +153,7 @@ func TestCalcPriority(t *testing.T) {
 			name: "one height 7 input, prio tx height 100000",
 			tx:   commonRedeemTx1,
 			utxoSet: newUTXOSet([]*wire.MsgTx{commonSourceTx1},
-				[]int32{7}),
+				[]uint64{7}),
 			nextHeight: 100000,
 			want:       6.943958333333333e+12,
 		},
@@ -161,7 +161,7 @@ func TestCalcPriority(t *testing.T) {
 			name: "one height 100 input, prio tx height 100000",
 			tx:   commonRedeemTx1,
 			utxoSet: newUTXOSet([]*wire.MsgTx{commonSourceTx1},
-				[]int32{100}),
+				[]uint64{100}),
 			nextHeight: 100000,
 			want:       6.9375e+12,
 		},
diff --git a/mining/simulator/client.go b/mining/simulator/client.go
index f5df3228f..b9914fe74 100644
--- a/mining/simulator/client.go
+++ b/mining/simulator/client.go
@@ -19,7 +19,7 @@ func newSimulatorClient(address string, connCfg *rpcclient.ConnConfig) (*simulat
 		onBlockAdded: make(chan struct{}, 1),
 	}
 	notificationHandlers := &rpcclient.NotificationHandlers{
-		OnFilteredBlockAdded: func(height int32, header *wire.BlockHeader,
+		OnFilteredBlockAdded: func(height uint64, header *wire.BlockHeader,
 			txs []*util.Tx) {
 			if client.notifyForNewBlocks {
 				client.onBlockAdded <- struct{}{}
diff --git a/netsync/manager.go b/netsync/manager.go
index 44d771f39..0e0319c65 100644
--- a/netsync/manager.go
+++ b/netsync/manager.go
@@ -123,7 +123,7 @@ type pauseMsg struct {
 // headerNode is used as a node in a list of headers that are linked together
 // between checkpoints.
 type headerNode struct {
-	height int32
+	height uint64
 	hash   *daghash.Hash
 }
 
@@ -180,7 +180,7 @@ type SyncManager struct {
 
 // resetHeaderState sets the headers-first mode state to values appropriate for
 // syncing from a new peer.
-func (sm *SyncManager) resetHeaderState(newestHash *daghash.Hash, newestHeight int32) {
+func (sm *SyncManager) resetHeaderState(newestHash *daghash.Hash, newestHeight uint64) {
 	sm.headersFirstMode = false
 	sm.headerList.Init()
 	sm.startHeader = nil
@@ -198,7 +198,7 @@ func (sm *SyncManager) resetHeaderState(newestHash *daghash.Hash, newestHeight i
 // It returns nil when there is not one either because the height is already
 // later than the final checkpoint or some other reason such as disabled
 // checkpoints.
-func (sm *SyncManager) findNextHeaderCheckpoint(height int32) *dagconfig.Checkpoint {
+func (sm *SyncManager) findNextHeaderCheckpoint(height uint64) *dagconfig.Checkpoint {
 	checkpoints := sm.dag.Checkpoints()
 	if len(checkpoints) == 0 {
 		return nil
diff --git a/rpcclient/dag.go b/rpcclient/dag.go
index 9ee24a263..2a5b9c003 100644
--- a/rpcclient/dag.go
+++ b/rpcclient/dag.go
@@ -640,7 +640,7 @@ func (c *Client) VerifyDAG() (bool, error) {
 // the returned instance.
 //
 // See VerifyDAGLevel for the blocking version and more details.
-func (c *Client) VerifyDAGLevelAsync(checkLevel int32) FutureVerifyDAGResult {
+func (c *Client) VerifyDAGLevelAsync(checkLevel uint64) FutureVerifyDAGResult {
 	cmd := btcjson.NewVerifyDAGCmd(&checkLevel, nil)
 	return c.sendCmd(cmd)
 }
@@ -654,7 +654,7 @@ func (c *Client) VerifyDAGLevelAsync(checkLevel int32) FutureVerifyDAGResult {
 //
 // See VerifyDAG to use the default check level and VerifyDAGBlocks to
 // override the number of blocks to verify.
-func (c *Client) VerifyDAGLevel(checkLevel int32) (bool, error) {
+func (c *Client) VerifyDAGLevel(checkLevel uint64) (bool, error) {
 	return c.VerifyDAGLevelAsync(checkLevel).Receive()
 }
 
@@ -663,7 +663,7 @@ func (c *Client) VerifyDAGLevel(checkLevel int32) (bool, error) {
 // the returned instance.
 //
 // See VerifyDAGBlocks for the blocking version and more details.
-func (c *Client) VerifyDAGBlocksAsync(checkLevel, numBlocks int32) FutureVerifyDAGResult {
+func (c *Client) VerifyDAGBlocksAsync(checkLevel, numBlocks uint64) FutureVerifyDAGResult {
 	cmd := btcjson.NewVerifyDAGCmd(&checkLevel, &numBlocks)
 	return c.sendCmd(cmd)
 }
@@ -679,7 +679,7 @@ func (c *Client) VerifyDAGBlocksAsync(checkLevel, numBlocks int32) FutureVerifyD
 // current longest dag.
 //
 // See VerifyDAG and VerifyDAGLevel to use defaults.
-func (c *Client) VerifyDAGBlocks(checkLevel, numBlocks int32) (bool, error) {
+func (c *Client) VerifyDAGBlocks(checkLevel, numBlocks uint64) (bool, error) {
 	return c.VerifyDAGBlocksAsync(checkLevel, numBlocks).Receive()
 }
 
diff --git a/rpcclient/examples/btcdwebsockets/main.go b/rpcclient/examples/btcdwebsockets/main.go
index b13a51216..310a6ea68 100644
--- a/rpcclient/examples/btcdwebsockets/main.go
+++ b/rpcclient/examples/btcdwebsockets/main.go
@@ -21,7 +21,7 @@ func main() {
 	// for notifications.  See the documentation of the rpcclient
 	// NotificationHandlers type for more details about each handler.
 	ntfnHandlers := rpcclient.NotificationHandlers{
-		OnFilteredBlockAdded: func(height int32, header *wire.BlockHeader, txns []*util.Tx) {
+		OnFilteredBlockAdded: func(height uint64, header *wire.BlockHeader, txns []*util.Tx) {
 			log.Printf("Block added: %s (%d) %s",
 				header.BlockHash(), height, header.Timestamp)
 		},
diff --git a/rpcclient/extensions.go b/rpcclient/extensions.go
index dbca5e1ee..13bc0231a 100644
--- a/rpcclient/extensions.go
+++ b/rpcclient/extensions.go
@@ -152,7 +152,7 @@ type FutureGetBestBlockResult chan *response
 
 // Receive waits for the response promised by the future and returns the hash
 // and height of the block in the longest (best) chain.
-func (r FutureGetBestBlockResult) Receive() (*daghash.Hash, int32, error) {
+func (r FutureGetBestBlockResult) Receive() (*daghash.Hash, uint64, error) {
 	res, err := receiveFuture(r)
 	if err != nil {
 		return nil, 0, err
@@ -190,7 +190,7 @@ func (c *Client) GetBestBlockAsync() FutureGetBestBlockResult {
 // chain.
 //
 // NOTE: This is a btcd extension.
-func (c *Client) GetBestBlock() (*daghash.Hash, int32, error) {
+func (c *Client) GetBestBlock() (*daghash.Hash, uint64, error) {
 	return c.GetBestBlockAsync().Receive()
 }
 
diff --git a/rpcclient/notify.go b/rpcclient/notify.go
index 3fb88f317..bd633f00d 100644
--- a/rpcclient/notify.go
+++ b/rpcclient/notify.go
@@ -104,7 +104,7 @@ type NotificationHandlers struct {
 	// NotifyBlocks has been made to register for the notification and the
 	// function is non-nil.  Its parameters differ from OnBlockAdded: it
 	// receives the block's height, header, and relevant transactions.
-	OnFilteredBlockAdded func(height int32, header *wire.BlockHeader,
+	OnFilteredBlockAdded func(height uint64, header *wire.BlockHeader,
 		txs []*util.Tx)
 
 	// OnRecvTx is invoked when a transaction that receives funds to a
@@ -464,7 +464,7 @@ func parseDAGNtfnParams(params []json.RawMessage) (*daghash.Hash,
 //
 // NOTE: This is a btcd extension ported from github.com/decred/dcrrpcclient
 // and requires a websocket connection.
-func parseFilteredBlockAddedParams(params []json.RawMessage) (int32,
+func parseFilteredBlockAddedParams(params []json.RawMessage) (uint64,
 	*wire.BlockHeader, []*util.Tx, error) {
 
 	if len(params) < 3 {
@@ -472,7 +472,7 @@ func parseFilteredBlockAddedParams(params []json.RawMessage) (int32,
 	}
 
 	// Unmarshal first parameter as an integer.
-	var blockHeight int32
+	var blockHeight uint64
 	err := json.Unmarshal(params[0], &blockHeight)
 	if err != nil {
 		return 0, nil, nil, err
diff --git a/server/p2p/p2p.go b/server/p2p/p2p.go
index 3e0c6b14e..2c7555dbd 100644
--- a/server/p2p/p2p.go
+++ b/server/p2p/p2p.go
@@ -762,7 +762,7 @@ func (sp *Peer) OnGetCFilters(_ *peer.Peer, msg *wire.MsgGetCFilters) {
 		return
 	}
 
-	hashes, err := sp.server.DAG.HeightToHashRange(int32(msg.StartHeight),
+	hashes, err := sp.server.DAG.HeightToHashRange(msg.StartHeight,
 		msg.StopHash, wire.MaxGetCFiltersReqRange)
 	if err != nil {
 		peerLog.Debugf("Invalid getcfilters request: %s", err)
@@ -793,7 +793,7 @@ func (sp *Peer) OnGetCFHeaders(_ *peer.Peer, msg *wire.MsgGetCFHeaders) {
 		return
 	}
 
-	startHeight := int32(msg.StartHeight)
+	startHeight := msg.StartHeight
 	maxResults := wire.MaxCFHeadersPerMsg
 
 	// If StartHeight is positive, fetch the predecessor block hash so we can
@@ -2474,7 +2474,7 @@ func NewServer(listenAddrs []string, db database.DB, dagParams *dagconfig.Params
 			MaxTxVersion:         1,
 		},
 		DAGParams:      dagParams,
-		BestHeight:     func() int32 { return s.DAG.Height() }, //TODO: (Ori) This is probably wrong. Done only for compilation
+		BestHeight:     func() uint64 { return s.DAG.Height() }, //TODO: (Ori) This is probably wrong. Done only for compilation
 		MedianTimePast: func() time.Time { return s.DAG.CalcPastMedianTime() },
 		CalcSequenceLockNoLock: func(tx *util.Tx, utxoSet blockdag.UTXOSet) (*blockdag.SequenceLock, error) {
 			return s.DAG.CalcSequenceLockNoLock(tx, utxoSet, true)
@@ -2843,7 +2843,7 @@ func (s checkpointSorter) Less(i, j int) bool {
 func mergeCheckpoints(defaultCheckpoints, additional []dagconfig.Checkpoint) []dagconfig.Checkpoint {
 	// Create a map of the additional checkpoints to remove duplicates while
 	// leaving the most recently-specified checkpoint.
-	extra := make(map[int32]dagconfig.Checkpoint)
+	extra := make(map[uint64]dagconfig.Checkpoint)
 	for _, checkpoint := range additional {
 		extra[checkpoint.Height] = checkpoint
 	}
diff --git a/server/rpc/rpcserver.go b/server/rpc/rpcserver.go
index 161ec991e..0ecb1d795 100644
--- a/server/rpc/rpcserver.go
+++ b/server/rpc/rpcserver.go
@@ -746,7 +746,7 @@ func createVoutList(mtx *wire.MsgTx, chainParams *dagconfig.Params, filterAddrMa
 // to a raw transaction JSON object.
 func createTxRawResult(dagParams *dagconfig.Params, mtx *wire.MsgTx,
 	txID string, blkHeader *wire.BlockHeader, blkHash string,
-	blkHeight int32, chainHeight int32, acceptedBy *daghash.Hash) (*btcjson.TxRawResult, error) {
+	blkHeight uint64, chainHeight uint64, acceptedBy *daghash.Hash) (*btcjson.TxRawResult, error) {
 
 	mtxHex, err := messageToHex(mtx)
 	if err != nil {
@@ -1202,7 +1202,7 @@ func handleGetBlock(s *Server, cmd interface{}, closeChan <-chan struct{}) (inte
 		Nonce:         blockHeader.Nonce,
 		Time:          blockHeader.Timestamp.Unix(),
 		Confirmations: uint64(1 + s.cfg.DAG.Height() - blockHeight), //TODO: (Ori) This is probably wrong. Done only for compilation
-		Height:        int64(blockHeight),
+		Height:        blockHeight,
 		Size:          int32(len(blkBytes)),
 		Bits:          strconv.FormatInt(int64(blockHeader.Bits), 16),
 		Difficulty:    getDifficultyRatio(blockHeader.Bits, params),
@@ -1270,8 +1270,8 @@ func handleGetBlockDAGInfo(s *Server, cmd interface{}, closeChan <-chan struct{}
 
 	dagInfo := &btcjson.GetBlockDAGInfoResult{
 		DAG:           params.Name,
-		Blocks:        dag.Height(), //TODO: (Ori) This is wrong. Done only for compilation
-		Headers:       dag.Height(), //TODO: (Ori) This is wrong. Done only for compilation
+		Blocks:        dag.BlockCount(),
+		Headers:       dag.BlockCount(),
 		TipHashes:     daghash.Strings(dag.TipHashes()),
 		Difficulty:    getDifficultyRatio(dag.CurrentBits(), params),
 		MedianTime:    dag.CalcPastMedianTime().Unix(),
@@ -1782,7 +1782,7 @@ func (state *gbtWorkState) blockTemplateResult(useCoinbaseValue bool, submitOld
 	reply := btcjson.GetBlockTemplateResult{
 		Bits:         strconv.FormatInt(int64(header.Bits), 16),
 		CurTime:      header.Timestamp.Unix(),
-		Height:       int64(template.Height),
+		Height:       template.Height,
 		ParentHashes: daghash.Strings(header.ParentHashes),
 		SigOpLimit:   blockdag.MaxSigOpsPerBlock,
 		SizeLimit:    wire.MaxBlockPayload,
@@ -2370,7 +2370,7 @@ func handleGetInfo(s *Server, cmd interface{}, closeChan <-chan struct{}) (inter
 	ret := &btcjson.InfoDAGResult{
 		Version:         int32(1000000*version.AppMajor + 10000*version.AppMinor + 100*version.AppPatch),
 		ProtocolVersion: int32(maxProtocolVersion),
-		Blocks:          s.cfg.DAG.Height(), //TODO: (Ori) This is wrong. Done only for compilation
+		Blocks:          s.cfg.DAG.BlockCount(),
 		TimeOffset:      int64(s.cfg.TimeSource.Offset().Seconds()),
 		Connections:     s.cfg.ConnMgr.ConnectedCount(),
 		Proxy:           config.MainConfig().Proxy,
@@ -2552,7 +2552,7 @@ func handleGetRawTransaction(s *Server, cmd interface{}, closeChan <-chan struct
 	// try the block database.
 	var mtx *wire.MsgTx
 	var blkHash *daghash.Hash
-	var blkHeight int32
+	var blkHeight uint64
 	tx, err := s.cfg.TxMemPool.FetchTransaction(txID)
 	if err != nil {
 		if s.cfg.TxIndex == nil {
@@ -2630,7 +2630,7 @@ func handleGetRawTransaction(s *Server, cmd interface{}, closeChan <-chan struct
 	// The verbose flag is set, so generate the JSON object and return it.
 	var blkHeader *wire.BlockHeader
 	var blkHashStr string
-	var dagHeight int32
+	var dagHeight uint64
 	if blkHash != nil {
 		// Fetch the header from chain.
 		header, err := s.cfg.DAG.HeaderByHash(blkHash)
@@ -2665,7 +2665,7 @@ func handleGetTxOut(s *Server, cmd interface{}, closeChan <-chan struct{}) (inte
 	// If requested and the tx is available in the mempool try to fetch it
 	// from there, otherwise attempt to fetch from the block database.
 	var bestBlockHash string
-	var confirmations int32
+	var confirmations uint64
 	var value uint64
 	var pkScript []byte
 	var isCoinbase bool
@@ -3252,7 +3252,7 @@ func handleSearchRawTransactions(s *Server, cmd interface{}, closeChan <-chan st
 		// confirmations or block information).
 		var blkHeader *wire.BlockHeader
 		var blkHashStr string
-		var blkHeight int32
+		var blkHeight uint64
 		if blkHash := rtx.blkHash; blkHash != nil {
 			// Fetch the header from chain.
 			header, err := s.cfg.DAG.HeaderByHash(blkHash)
@@ -3476,7 +3476,7 @@ func handleValidateAddress(s *Server, cmd interface{}, closeChan <-chan struct{}
 	return result, nil
 }
 
-func verifyDAG(s *Server, level, depth int32) error {
+func verifyDAG(s *Server, level, depth uint64) error {
 	finishHeight := s.cfg.DAG.Height() - depth //TODO: (Ori) This is probably wrong. Done only for compilation
 	if finishHeight < 0 {
 		finishHeight = 0
@@ -3516,7 +3516,7 @@ func verifyDAG(s *Server, level, depth int32) error {
 func handleVerifyDAG(s *Server, cmd interface{}, closeChan <-chan struct{}) (interface{}, error) {
 	c := cmd.(*btcjson.VerifyDAGCmd)
 
-	var checkLevel, checkDepth int32
+	var checkLevel, checkDepth uint64
 	if c.CheckLevel != nil {
 		checkLevel = *c.CheckLevel
 	}
diff --git a/util/block.go b/util/block.go
index 7ebcb0be1..1c723fa54 100644
--- a/util/block.go
+++ b/util/block.go
@@ -8,6 +8,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"math"
 
 	"github.com/daglabs/btcd/dagconfig/daghash"
 	"github.com/daglabs/btcd/wire"
@@ -19,9 +20,8 @@ type OutOfRangeError string
 
 const (
 	// BlockHeightUnknown is the value returned for a block height that is unknown.
-	// This is typically because the block has not been inserted into the main chain
-	// yet.
-	BlockHeightUnknown = int32(-1)
+	// This is typically because the block has not been inserted into the DAG yet.
+	BlockHeightUnknown = math.MaxUint64
 
 	// CoinbaseTransactionIndex is the index of the coinbase transaction in every block
 	CoinbaseTransactionIndex = 0
@@ -44,7 +44,7 @@ type Block struct {
 	msgBlock        *wire.MsgBlock // Underlying MsgBlock
 	serializedBlock []byte         // Serialized bytes for the block
 	blockHash       *daghash.Hash  // Cached block hash
-	blockHeight     int32          // Height in the main block chain
+	blockHeight     uint64         // Height in the DAG
 	transactions    []*Tx          // Transactions
 	txnsGenerated   bool           // ALL wrapped transactions generated
 }
@@ -194,12 +194,12 @@ func (b *Block) TxLoc() ([]wire.TxLoc, error) {
 
 // Height returns the saved height of the block in the block chain.  This value
 // will be BlockHeightUnknown if it hasn't already explicitly been set.
-func (b *Block) Height() int32 {
+func (b *Block) Height() uint64 {
 	return b.blockHeight
 }
 
 // SetHeight sets the height of the block in the block chain.
-func (b *Block) SetHeight(height int32) {
+func (b *Block) SetHeight(height uint64) {
 	b.blockHeight = height
 }
 
diff --git a/util/block_test.go b/util/block_test.go
index 2ce205c8b..852bb5c05 100644
--- a/util/block_test.go
+++ b/util/block_test.go
@@ -30,7 +30,7 @@ func TestBlock(t *testing.T) {
 	}
 
 	// Ensure block height set and get work properly.
-	wantHeight := int32(100000)
+	wantHeight := uint64(100000)
 	b.SetHeight(wantHeight)
 	if gotHeight := b.Height(); gotHeight != wantHeight {
 		t.Errorf("Height: mismatched height - got %v, want %v",
diff --git a/util/btcmath.go b/util/btcmath.go
index 25e8ea9d3..1ee69a9d6 100644
--- a/util/btcmath.go
+++ b/util/btcmath.go
@@ -14,16 +14,16 @@ var (
 	oneLsh256 = new(big.Int).Lsh(bigOne, 256)
 
 	// log2FloorMasks defines the masks to use when quickly calculating
-	// floor(log2(x)) in a constant log2(32) = 5 steps, where x is a uint32, using
-	// shifts.  They are derived from (2^(2^x) - 1) * (2^(2^x)), for x in 4..0.
-	log2FloorMasks = []uint32{0xffff0000, 0xff00, 0xf0, 0xc, 0x2}
+	// floor(log2(x)) in a constant log2(64) = 6 steps, where x is a uint64, using
+	// shifts.  They are derived from (2^(2^x) - 1) * (2^(2^x)), for x in 5..0.
+	log2FloorMasks = []uint64{0xffffffff00000000, 0xffff0000, 0xff00, 0xf0, 0xc, 0x2}
 )
 
 // FastLog2Floor calculates and returns floor(log2(x)) in a constant 5 steps.
-func FastLog2Floor(n uint32) uint8 {
+func FastLog2Floor(n uint64) uint8 {
 	rv := uint8(0)
-	exponent := uint8(16)
-	for i := 0; i < 5; i++ {
+	exponent := uint8(32)
+	for i := 0; i < 6; i++ {
 		if n&log2FloorMasks[i] != 0 {
 			rv += exponent
 			n >>= exponent
diff --git a/util/btcmath_test.go b/util/btcmath_test.go
new file mode 100644
index 000000000..1cd6a0b86
--- /dev/null
+++ b/util/btcmath_test.go
@@ -0,0 +1,35 @@
+package util
+
+import (
+	"testing"
+)
+
+func TestFastLog2Floor(t *testing.T) {
+	tests := []struct {
+		n              uint64
+		expectedResult uint8
+	}{
+		{1, 0},
+		{2, 1},
+		{3, 1},
+		{4, 2},
+		{5, 2},
+		{16, 4},
+		{31, 4},
+		{1684234, 20},
+		{4294967295, 31}, // math.MaxUint32 (2^32 - 1)
+		{4294967296, 32}, // 2^32
+		{4294967297, 32}, // 2^32 + 1
+		{4611686018427387904, 62},
+		{9223372036854775808, 63},  // 2^63
+		{18446744073709551615, 63}, // math.MaxUint64 (2^64 - 1).
+	}
+
+	for _, test := range tests {
+		actualResult := FastLog2Floor(test.n)
+
+		if test.expectedResult != actualResult {
+			t.Errorf("TestFastLog2Floor: %d: expected result: %d but got: %d", test.n, test.expectedResult, actualResult)
+		}
+	}
+}
diff --git a/wire/message_test.go b/wire/message_test.go
index 3172a9f34..d81e9dbc8 100644
--- a/wire/message_test.go
+++ b/wire/message_test.go
@@ -109,8 +109,8 @@ func TestMessage(t *testing.T) {
 		{msgFilterLoad, msgFilterLoad, pver, MainNet, 35},
 		{msgMerkleBlock, msgMerkleBlock, pver, MainNet, 183},
 		{msgReject, msgReject, pver, MainNet, 79},
-		{msgGetCFilters, msgGetCFilters, pver, MainNet, 61},
-		{msgGetCFHeaders, msgGetCFHeaders, pver, MainNet, 61},
+		{msgGetCFilters, msgGetCFilters, pver, MainNet, 65},
+		{msgGetCFHeaders, msgGetCFHeaders, pver, MainNet, 65},
 		{msgGetCFCheckpt, msgGetCFCheckpt, pver, MainNet, 57},
 		{msgCFilter, msgCFilter, pver, MainNet, 65},
 		{msgCFHeaders, msgCFHeaders, pver, MainNet, 90},
diff --git a/wire/msggetcfheaders.go b/wire/msggetcfheaders.go
index 33734f24e..66997bcdd 100644
--- a/wire/msggetcfheaders.go
+++ b/wire/msggetcfheaders.go
@@ -15,7 +15,7 @@ import (
 // chain of basic (0x00) or extended (0x01) headers.
 type MsgGetCFHeaders struct {
 	FilterType  FilterType
-	StartHeight uint32
+	StartHeight uint64
 	StopHash    *daghash.Hash
 }
 
@@ -61,14 +61,14 @@ func (msg *MsgGetCFHeaders) Command() string {
 // MaxPayloadLength returns the maximum length the payload can be for the
 // receiver.  This is part of the Message interface implementation.
 func (msg *MsgGetCFHeaders) MaxPayloadLength(pver uint32) uint32 {
-	// Filter type + uint32 + block hash
-	return 1 + 4 + daghash.HashSize
+	// Filter type + uint64 + block hash
+	return 1 + 8 + daghash.HashSize
 }
 
 // NewMsgGetCFHeaders returns a new bitcoin getcfheader message that conforms to
 // the Message interface using the passed parameters and defaults for the
 // remaining fields.
-func NewMsgGetCFHeaders(filterType FilterType, startHeight uint32,
+func NewMsgGetCFHeaders(filterType FilterType, startHeight uint64,
 	stopHash *daghash.Hash) *MsgGetCFHeaders {
 	return &MsgGetCFHeaders{
 		FilterType:  filterType,
diff --git a/wire/msggetcfilters.go b/wire/msggetcfilters.go
index 4b4abf0e7..aeb4a2afc 100644
--- a/wire/msggetcfilters.go
+++ b/wire/msggetcfilters.go
@@ -19,7 +19,7 @@ const MaxGetCFiltersReqRange = 1000
 // blocks.
 type MsgGetCFilters struct {
 	FilterType  FilterType
-	StartHeight uint32
+	StartHeight uint64
 	StopHash    *daghash.Hash
 }
 
@@ -65,14 +65,14 @@ func (msg *MsgGetCFilters) Command() string {
 // MaxPayloadLength returns the maximum length the payload can be for the
 // receiver.  This is part of the Message interface implementation.
 func (msg *MsgGetCFilters) MaxPayloadLength(pver uint32) uint32 {
-	// Filter type + uint32 + block hash
-	return 1 + 4 + daghash.HashSize
+	// Filter type + uint64 + block hash
+	return 1 + 8 + daghash.HashSize
 }
 
 // NewMsgGetCFilters returns a new bitcoin getcfilters message that conforms to
 // the Message interface using the passed parameters and defaults for the
 // remaining fields.
-func NewMsgGetCFilters(filterType FilterType, startHeight uint32,
+func NewMsgGetCFilters(filterType FilterType, startHeight uint64,
 	stopHash *daghash.Hash) *MsgGetCFilters {
 	return &MsgGetCFilters{
 		FilterType:  filterType,