diff --git a/blockdag/blockheap.go b/blockdag/blockheap.go
index 5c79f3563..4bb28b0bb 100644
--- a/blockdag/blockheap.go
+++ b/blockdag/blockheap.go
@@ -46,43 +46,43 @@ func (h downHeap) Less(i, j int) bool {
 	return h.baseHeap[i].height > h.baseHeap[j].height
 }
 
-// BlockHeap represents a mutable heap of Blocks, sorted by their height
-type BlockHeap struct {
+// blockHeap represents a mutable heap of Blocks, sorted by their height
+type blockHeap struct {
 	impl heap.Interface
 }
 
-// NewDownHeap initializes and returns a new BlockHeap
-func NewDownHeap() BlockHeap {
-	h := BlockHeap{impl: &downHeap{}}
+// newDownHeap initializes and returns a new blockHeap
+func newDownHeap() blockHeap {
+	h := blockHeap{impl: &downHeap{}}
 	heap.Init(h.impl)
 	return h
 }
 
-// NewUpHeap initializes and returns a new BlockHeap
-func NewUpHeap() BlockHeap {
-	h := BlockHeap{impl: &upHeap{}}
+// newUpHeap initializes and returns a new blockHeap
+func newUpHeap() blockHeap {
+	h := blockHeap{impl: &upHeap{}}
 	heap.Init(h.impl)
 	return h
 }
 
 // pop removes the block with lowest height from this heap and returns it
-func (bh BlockHeap) pop() *blockNode {
+func (bh blockHeap) pop() *blockNode {
 	return heap.Pop(bh.impl).(*blockNode)
 }
 
 // Push pushes the block onto the heap
-func (bh BlockHeap) Push(block *blockNode) {
+func (bh blockHeap) Push(block *blockNode) {
 	heap.Push(bh.impl, block)
 }
 
 // pushSet pushes a blockset to the heap.
-func (bh BlockHeap) pushSet(bs blockSet) {
+func (bh blockHeap) pushSet(bs blockSet) {
 	for _, block := range bs {
 		heap.Push(bh.impl, block)
 	}
 }
 
 // Len returns the length of this heap
-func (bh BlockHeap) Len() int {
+func (bh blockHeap) Len() int {
 	return bh.impl.Len()
 }
diff --git a/blockdag/blockheap_test.go b/blockdag/blockheap_test.go
index 879cda046..5828bbb5a 100644
--- a/blockdag/blockheap_test.go
+++ b/blockdag/blockheap_test.go
@@ -81,7 +81,7 @@ func TestBlockHeap(t *testing.T) {
 	}
 
 	for _, test := range tests {
-		dHeap := NewDownHeap()
+		dHeap := newDownHeap()
 		for _, block := range test.toPush {
 			dHeap.Push(block)
 		}
@@ -99,7 +99,7 @@ func TestBlockHeap(t *testing.T) {
 				"Expected: %v, got: %v", test.name, test.expectedPopDown, poppedBlock)
 		}
 
-		uHeap := NewUpHeap()
+		uHeap := newUpHeap()
 		for _, block := range test.toPush {
 			uHeap.Push(block)
 		}
diff --git a/blockdag/dag.go b/blockdag/dag.go
index 79a05489a..36857ac82 100644
--- a/blockdag/dag.go
+++ b/blockdag/dag.go
@@ -1439,7 +1439,7 @@ func (dag *BlockDAG) locateBlockNodes(locator BlockLocator, hashStop *daghash.Ha
 
 	// Populate and return the found nodes.
 	nodes := make([]*blockNode, 0, estimatedEntries)
-	queue := NewUpHeap()
+	queue := newUpHeap()
 	queue.pushSet(node.children)
 
 	visited := newSet()
@@ -1506,7 +1506,7 @@ func (dag *BlockDAG) GetTopHeaders(startHash *daghash.Hash) ([]*wire.BlockHeader
 		}
 	}
 	headers := make([]*wire.BlockHeader, 0, startNode.blueScore)
-	queue := NewDownHeap()
+	queue := newDownHeap()
 	queue.pushSet(startNode.parents)
 
 	visited := newSet()
diff --git a/blockdag/phantom.go b/blockdag/phantom.go
index c574eb5f7..63ffc156f 100644
--- a/blockdag/phantom.go
+++ b/blockdag/phantom.go
@@ -77,7 +77,7 @@ func blueCandidates(chainStart *blockNode) blockSet {
 func traverseCandidates(newBlock *blockNode, candidates blockSet, selectedParent *blockNode) []*blockNode {
 	blues := []*blockNode{}
 	selectedParentPast := newSet()
-	queue := NewDownHeap()
+	queue := newDownHeap()
 	visited := newSet()
 
 	for _, parent := range newBlock.parents {
diff --git a/blockdag/validate.go b/blockdag/validate.go
index 524b35543..043d3d6ae 100644
--- a/blockdag/validate.go
+++ b/blockdag/validate.go
@@ -754,7 +754,7 @@ 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)
-	queue := NewDownHeap()
+	queue := newDownHeap()
 	visited := newSet()
 	for _, parent := range parents {
 		if parent.height < minHeight {