diff --git a/internal/hash/hash.go b/internal/hash/hash.go
index 55316c1..9a40e71 100644
--- a/internal/hash/hash.go
+++ b/internal/hash/hash.go
@@ -1,5 +1,6 @@
 package hash
 
+// FNV64a computes FNV-1a hash without allocation.
 func FNV64a(key string) uint64 {
 	var h uint64 = 14695981039346656037
 	for i := 0; i < len(key); i++ {
@@ -9,6 +10,7 @@ func FNV64a(key string) uint64 {
 	return h
 }
 
+// FNV64aBytes computes FNV-1a hash from byte slice without allocation.
 func FNV64aBytes(key []byte) uint64 {
 	var h uint64 = 14695981039346656037
 	for i := 0; i < len(key); i++ {
diff --git a/internal/utils/bytes.go b/internal/utils/bytes.go
index 4ca1650..1c09d8a 100644
--- a/internal/utils/bytes.go
+++ b/internal/utils/bytes.go
@@ -30,6 +30,7 @@ func S2b(s string) []byte {
 	return unsafe.Slice(unsafe.StringData(s), len(s))
 }
 
+// BytesContainsFold reports whether b contains subslice, case-insensitively.
 func BytesContainsFold(b, sub []byte) bool {
 	if len(sub) == 0 {
 		return true